1 //===- unittest/AST/ASTImporterTest.cpp - AST node import test ------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Tests for the correct import of AST nodes from one AST context to another.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/ASTMatchers/ASTMatchers.h"
14 #include "llvm/ADT/StringMap.h"
15 #include "llvm/Support/SmallVectorMemoryBuffer.h"
16 
17 #include "clang/AST/DeclContextInternals.h"
18 #include "gtest/gtest.h"
19 
20 #include "ASTImporterFixtures.h"
21 
22 namespace clang {
23 namespace ast_matchers {
24 
25 using internal::Matcher;
26 using internal::BindableMatcher;
27 using llvm::StringMap;
28 
29 static const RecordDecl *getRecordDeclOfFriend(FriendDecl *FD) {
30   QualType Ty = FD->getFriendType()->getType().getCanonicalType();
31   return cast<RecordType>(Ty)->getDecl();
32 }
33 
34 struct ImportExpr : TestImportBase {};
35 struct ImportType : TestImportBase {};
36 struct ImportDecl : TestImportBase {};
37 struct ImportFixedPointExpr : ImportExpr {};
38 
39 struct CanonicalRedeclChain : ASTImporterOptionSpecificTestBase {};
40 
41 TEST_P(CanonicalRedeclChain, ShouldBeConsequentWithMatchers) {
42   Decl *FromTU = getTuDecl("void f();", Lang_CXX03);
43   auto Pattern = functionDecl(hasName("f"));
44   auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
45 
46   auto Redecls = getCanonicalForwardRedeclChain(D0);
47   ASSERT_EQ(Redecls.size(), 1u);
48   EXPECT_EQ(D0, Redecls[0]);
49 }
50 
51 TEST_P(CanonicalRedeclChain, ShouldBeConsequentWithMatchers2) {
52   Decl *FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX03);
53   auto Pattern = functionDecl(hasName("f"));
54   auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
55   auto *D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
56   FunctionDecl *D1 = D2->getPreviousDecl();
57 
58   auto Redecls = getCanonicalForwardRedeclChain(D0);
59   ASSERT_EQ(Redecls.size(), 3u);
60   EXPECT_EQ(D0, Redecls[0]);
61   EXPECT_EQ(D1, Redecls[1]);
62   EXPECT_EQ(D2, Redecls[2]);
63 }
64 
65 TEST_P(CanonicalRedeclChain, ShouldBeSameForAllDeclInTheChain) {
66   Decl *FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX03);
67   auto Pattern = functionDecl(hasName("f"));
68   auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
69   auto *D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
70   FunctionDecl *D1 = D2->getPreviousDecl();
71 
72   auto RedeclsD0 = getCanonicalForwardRedeclChain(D0);
73   auto RedeclsD1 = getCanonicalForwardRedeclChain(D1);
74   auto RedeclsD2 = getCanonicalForwardRedeclChain(D2);
75 
76   EXPECT_THAT(RedeclsD0, ::testing::ContainerEq(RedeclsD1));
77   EXPECT_THAT(RedeclsD1, ::testing::ContainerEq(RedeclsD2));
78 }
79 
80 namespace {
81 struct RedirectingImporter : public ASTImporter {
82   using ASTImporter::ASTImporter;
83 
84 protected:
85   llvm::Expected<Decl *> ImportImpl(Decl *FromD) override {
86     auto *ND = dyn_cast<NamedDecl>(FromD);
87     if (!ND || ND->getName() != "shouldNotBeImported")
88       return ASTImporter::ImportImpl(FromD);
89     for (Decl *D : getToContext().getTranslationUnitDecl()->decls()) {
90       if (auto *ND = dyn_cast<NamedDecl>(D))
91         if (ND->getName() == "realDecl") {
92           RegisterImportedDecl(FromD, ND);
93           return ND;
94         }
95     }
96     return ASTImporter::ImportImpl(FromD);
97   }
98 };
99 
100 } // namespace
101 
102 struct RedirectingImporterTest : ASTImporterOptionSpecificTestBase {
103   RedirectingImporterTest() {
104     Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
105                  ASTContext &FromContext, FileManager &FromFileManager,
106                  bool MinimalImport,
107                  const std::shared_ptr<ASTImporterSharedState> &SharedState) {
108       return new RedirectingImporter(ToContext, ToFileManager, FromContext,
109                                      FromFileManager, MinimalImport,
110                                      SharedState);
111     };
112   }
113 };
114 
115 // Test that an ASTImporter subclass can intercept an import call.
116 TEST_P(RedirectingImporterTest, InterceptImport) {
117   Decl *From, *To;
118   std::tie(From, To) =
119       getImportedDecl("class shouldNotBeImported {};", Lang_CXX03,
120                       "class realDecl {};", Lang_CXX03, "shouldNotBeImported");
121   auto *Imported = cast<CXXRecordDecl>(To);
122   EXPECT_EQ(Imported->getQualifiedNameAsString(), "realDecl");
123 
124   // Make sure our importer prevented the importing of the decl.
125   auto *ToTU = Imported->getTranslationUnitDecl();
126   auto Pattern = functionDecl(hasName("shouldNotBeImported"));
127   unsigned count =
128       DeclCounterWithPredicate<CXXRecordDecl>().match(ToTU, Pattern);
129   EXPECT_EQ(0U, count);
130 }
131 
132 // Test that when we indirectly import a declaration the custom ASTImporter
133 // is still intercepting the import.
134 TEST_P(RedirectingImporterTest, InterceptIndirectImport) {
135   Decl *From, *To;
136   std::tie(From, To) =
137       getImportedDecl("class shouldNotBeImported {};"
138                       "class F { shouldNotBeImported f; };",
139                       Lang_CXX03, "class realDecl {};", Lang_CXX03, "F");
140 
141   // Make sure our ASTImporter prevented the importing of the decl.
142   auto *ToTU = To->getTranslationUnitDecl();
143   auto Pattern = functionDecl(hasName("shouldNotBeImported"));
144   unsigned count =
145       DeclCounterWithPredicate<CXXRecordDecl>().match(ToTU, Pattern);
146   EXPECT_EQ(0U, count);
147 }
148 
149 struct ImportPath : ASTImporterOptionSpecificTestBase {
150   Decl *FromTU;
151   FunctionDecl *D0, *D1, *D2;
152   ImportPath() {
153     FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX03);
154     auto Pattern = functionDecl(hasName("f"));
155     D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
156     D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
157     D1 = D2->getPreviousDecl();
158   }
159 };
160 
161 TEST_P(ImportPath, Push) {
162   ASTImporter::ImportPathTy path;
163   path.push(D0);
164   EXPECT_FALSE(path.hasCycleAtBack());
165 }
166 
167 TEST_P(ImportPath, SmallCycle) {
168   ASTImporter::ImportPathTy path;
169   path.push(D0);
170   path.push(D0);
171   EXPECT_TRUE(path.hasCycleAtBack());
172   path.pop();
173   EXPECT_FALSE(path.hasCycleAtBack());
174   path.push(D0);
175   EXPECT_TRUE(path.hasCycleAtBack());
176 }
177 
178 TEST_P(ImportPath, GetSmallCycle) {
179   ASTImporter::ImportPathTy path;
180   path.push(D0);
181   path.push(D0);
182   EXPECT_TRUE(path.hasCycleAtBack());
183   std::array<Decl* ,2> Res;
184   int i = 0;
185   for (Decl *Di : path.getCycleAtBack()) {
186     Res[i++] = Di;
187   }
188   ASSERT_EQ(i, 2);
189   EXPECT_EQ(Res[0], D0);
190   EXPECT_EQ(Res[1], D0);
191 }
192 
193 TEST_P(ImportPath, GetCycle) {
194   ASTImporter::ImportPathTy path;
195   path.push(D0);
196   path.push(D1);
197   path.push(D2);
198   path.push(D0);
199   EXPECT_TRUE(path.hasCycleAtBack());
200   std::array<Decl* ,4> Res;
201   int i = 0;
202   for (Decl *Di : path.getCycleAtBack()) {
203     Res[i++] = Di;
204   }
205   ASSERT_EQ(i, 4);
206   EXPECT_EQ(Res[0], D0);
207   EXPECT_EQ(Res[1], D2);
208   EXPECT_EQ(Res[2], D1);
209   EXPECT_EQ(Res[3], D0);
210 }
211 
212 TEST_P(ImportPath, CycleAfterCycle) {
213   ASTImporter::ImportPathTy path;
214   path.push(D0);
215   path.push(D1);
216   path.push(D0);
217   path.push(D1);
218   path.push(D2);
219   path.push(D0);
220   EXPECT_TRUE(path.hasCycleAtBack());
221   std::array<Decl* ,4> Res;
222   int i = 0;
223   for (Decl *Di : path.getCycleAtBack()) {
224     Res[i++] = Di;
225   }
226   ASSERT_EQ(i, 4);
227   EXPECT_EQ(Res[0], D0);
228   EXPECT_EQ(Res[1], D2);
229   EXPECT_EQ(Res[2], D1);
230   EXPECT_EQ(Res[3], D0);
231 
232   path.pop();
233   path.pop();
234   path.pop();
235   EXPECT_TRUE(path.hasCycleAtBack());
236   i = 0;
237   for (Decl *Di : path.getCycleAtBack()) {
238     Res[i++] = Di;
239   }
240   ASSERT_EQ(i, 3);
241   EXPECT_EQ(Res[0], D0);
242   EXPECT_EQ(Res[1], D1);
243   EXPECT_EQ(Res[2], D0);
244 
245   path.pop();
246   EXPECT_FALSE(path.hasCycleAtBack());
247 }
248 
249 const internal::VariadicDynCastAllOfMatcher<Stmt, SourceLocExpr> sourceLocExpr;
250 
251 AST_MATCHER_P(SourceLocExpr, hasBuiltinStr, StringRef, Str) {
252   return Node.getBuiltinStr() == Str;
253 }
254 
255 TEST_P(ImportExpr, ImportSourceLocExpr) {
256   MatchVerifier<Decl> Verifier;
257   testImport("void declToImport() { (void)__builtin_FILE(); }", Lang_CXX03, "",
258              Lang_CXX03, Verifier,
259              functionDecl(hasDescendant(
260                  sourceLocExpr(hasBuiltinStr("__builtin_FILE")))));
261   testImport("void declToImport() { (void)__builtin_COLUMN(); }", Lang_CXX03,
262              "", Lang_CXX03, Verifier,
263              functionDecl(hasDescendant(
264                  sourceLocExpr(hasBuiltinStr("__builtin_COLUMN")))));
265 }
266 
267 TEST_P(ImportExpr, ImportStringLiteral) {
268   MatchVerifier<Decl> Verifier;
269   testImport("void declToImport() { (void)\"foo\"; }", Lang_CXX03, "",
270              Lang_CXX03, Verifier,
271              functionDecl(hasDescendant(
272                  stringLiteral(hasType(asString("const char[4]"))))));
273   testImport("void declToImport() { (void)L\"foo\"; }", Lang_CXX03, "",
274              Lang_CXX03, Verifier,
275              functionDecl(hasDescendant(
276                  stringLiteral(hasType(asString("const wchar_t[4]"))))));
277   testImport("void declToImport() { (void) \"foo\" \"bar\"; }", Lang_CXX03, "",
278              Lang_CXX03, Verifier,
279              functionDecl(hasDescendant(
280                  stringLiteral(hasType(asString("const char[7]"))))));
281 }
282 
283 TEST_P(ImportExpr, ImportChooseExpr) {
284   MatchVerifier<Decl> Verifier;
285 
286   // This case tests C code that is not condition-dependent and has a true
287   // condition.
288   testImport("void declToImport() { (void)__builtin_choose_expr(1, 2, 3); }",
289              Lang_C99, "", Lang_C99, Verifier,
290              functionDecl(hasDescendant(chooseExpr())));
291 }
292 
293 const internal::VariadicDynCastAllOfMatcher<Stmt, ShuffleVectorExpr>
294     shuffleVectorExpr;
295 
296 TEST_P(ImportExpr, ImportShuffleVectorExpr) {
297   MatchVerifier<Decl> Verifier;
298   constexpr auto Code = R"code(
299     typedef double vector4double __attribute__((__vector_size__(32)));
300     vector4double declToImport(vector4double a, vector4double b) {
301       return __builtin_shufflevector(a, b, 0, 1, 2, 3);
302     }
303   )code";
304   const auto Pattern = functionDecl(hasDescendant(shuffleVectorExpr(
305       allOf(has(declRefExpr(to(parmVarDecl(hasName("a"))))),
306             has(declRefExpr(to(parmVarDecl(hasName("b"))))),
307             has(integerLiteral(equals(0))), has(integerLiteral(equals(1))),
308             has(integerLiteral(equals(2))), has(integerLiteral(equals(3)))))));
309   testImport(Code, Lang_C99, "", Lang_C99, Verifier, Pattern);
310 }
311 
312 TEST_P(ImportExpr, ImportGNUNullExpr) {
313   MatchVerifier<Decl> Verifier;
314   testImport("void declToImport() { (void)__null; }", Lang_CXX03, "",
315              Lang_CXX03, Verifier,
316              functionDecl(hasDescendant(gnuNullExpr(hasType(isInteger())))));
317 }
318 
319 TEST_P(ImportExpr, ImportGenericSelectionExpr) {
320   MatchVerifier<Decl> Verifier;
321 
322   testImport(
323       "void declToImport() { int x; (void)_Generic(x, int: 0, float: 1); }",
324       Lang_C99, "", Lang_C99, Verifier,
325       functionDecl(hasDescendant(genericSelectionExpr())));
326 }
327 
328 TEST_P(ImportExpr, ImportCXXNullPtrLiteralExpr) {
329   MatchVerifier<Decl> Verifier;
330   testImport(
331       "void declToImport() { (void)nullptr; }",
332       Lang_CXX11, "", Lang_CXX11, Verifier,
333       functionDecl(hasDescendant(cxxNullPtrLiteralExpr())));
334 }
335 
336 
337 TEST_P(ImportExpr, ImportFloatinglLiteralExpr) {
338   MatchVerifier<Decl> Verifier;
339   testImport("void declToImport() { (void)1.0; }", Lang_C99, "", Lang_C99,
340              Verifier,
341              functionDecl(hasDescendant(
342                  floatLiteral(equals(1.0), hasType(asString("double"))))));
343   testImport("void declToImport() { (void)1.0e-5f; }", Lang_C99, "", Lang_C99,
344              Verifier,
345              functionDecl(hasDescendant(
346                  floatLiteral(equals(1.0e-5f), hasType(asString("float"))))));
347 }
348 
349 TEST_P(ImportFixedPointExpr, ImportFixedPointerLiteralExpr) {
350   MatchVerifier<Decl> Verifier;
351   testImport("void declToImport() { (void)1.0k; }", Lang_C99, "", Lang_C99,
352              Verifier, functionDecl(hasDescendant(fixedPointLiteral())));
353   testImport("void declToImport() { (void)0.75r; }", Lang_C99, "", Lang_C99,
354              Verifier, functionDecl(hasDescendant(fixedPointLiteral())));
355 }
356 
357 TEST_P(ImportExpr, ImportImaginaryLiteralExpr) {
358   MatchVerifier<Decl> Verifier;
359   testImport(
360       "void declToImport() { (void)1.0i; }",
361       Lang_CXX14, "", Lang_CXX14, Verifier,
362       functionDecl(hasDescendant(imaginaryLiteral())));
363 }
364 
365 TEST_P(ImportExpr, ImportCompoundLiteralExpr) {
366   MatchVerifier<Decl> Verifier;
367   testImport("void declToImport() {"
368              "  struct s { int x; long y; unsigned z; }; "
369              "  (void)(struct s){ 42, 0L, 1U }; }",
370              Lang_CXX03, "", Lang_CXX03, Verifier,
371              functionDecl(hasDescendant(compoundLiteralExpr(
372                  hasType(asString("struct s")),
373                  has(initListExpr(
374                      hasType(asString("struct s")),
375                      has(integerLiteral(equals(42), hasType(asString("int")))),
376                      has(integerLiteral(equals(0), hasType(asString("long")))),
377                      has(integerLiteral(
378                          equals(1), hasType(asString("unsigned int"))))))))));
379 }
380 
381 TEST_P(ImportExpr, ImportCXXThisExpr) {
382   MatchVerifier<Decl> Verifier;
383   testImport("class declToImport { void f() { (void)this; } };", Lang_CXX03, "",
384              Lang_CXX03, Verifier,
385              cxxRecordDecl(hasMethod(hasDescendant(
386                  cxxThisExpr(hasType(asString("class declToImport *")))))));
387 }
388 
389 TEST_P(ImportExpr, ImportAtomicExpr) {
390   MatchVerifier<Decl> Verifier;
391   testImport("void declToImport() { int *ptr; __atomic_load_n(ptr, 1); }",
392              Lang_C99, "", Lang_C99, Verifier,
393              functionDecl(hasDescendant(atomicExpr(
394                  has(ignoringParenImpCasts(
395                      declRefExpr(hasDeclaration(varDecl(hasName("ptr"))),
396                                  hasType(asString("int *"))))),
397                  has(integerLiteral(equals(1), hasType(asString("int"))))))));
398 }
399 
400 TEST_P(ImportExpr, ImportLabelDeclAndAddrLabelExpr) {
401   MatchVerifier<Decl> Verifier;
402   testImport("void declToImport() { loop: goto loop; (void)&&loop; }", Lang_C99,
403              "", Lang_C99, Verifier,
404              functionDecl(hasDescendant(labelStmt(
405                               hasDeclaration(labelDecl(hasName("loop"))))),
406                           hasDescendant(addrLabelExpr(
407                               hasDeclaration(labelDecl(hasName("loop")))))));
408 }
409 
410 AST_MATCHER_P(TemplateDecl, hasTemplateDecl,
411               internal::Matcher<NamedDecl>, InnerMatcher) {
412   const NamedDecl *Template = Node.getTemplatedDecl();
413   return Template && InnerMatcher.matches(*Template, Finder, Builder);
414 }
415 
416 TEST_P(ImportExpr, ImportParenListExpr) {
417   MatchVerifier<Decl> Verifier;
418   testImport(
419       "template<typename T> class dummy { void f() { dummy X(*this); } };"
420       "typedef dummy<int> declToImport;"
421       "template class dummy<int>;",
422       Lang_CXX03, "", Lang_CXX03, Verifier,
423       typedefDecl(hasType(templateSpecializationType(
424           hasDeclaration(classTemplateSpecializationDecl(hasSpecializedTemplate(
425               classTemplateDecl(hasTemplateDecl(cxxRecordDecl(hasMethod(allOf(
426                   hasName("f"),
427                   hasBody(compoundStmt(has(declStmt(hasSingleDecl(
428                       varDecl(hasInitializer(parenListExpr(has(unaryOperator(
429                           hasOperatorName("*"),
430                           hasUnaryOperand(cxxThisExpr())))))))))))))))))))))));
431 }
432 
433 TEST_P(ImportExpr, ImportSwitch) {
434   MatchVerifier<Decl> Verifier;
435   testImport("void declToImport() { int b; switch (b) { case 1: break; } }",
436              Lang_C99, "", Lang_C99, Verifier,
437              functionDecl(hasDescendant(
438                  switchStmt(has(compoundStmt(has(caseStmt())))))));
439 }
440 
441 TEST_P(ImportExpr, ImportStmtExpr) {
442   MatchVerifier<Decl> Verifier;
443   testImport(
444       "void declToImport() { int b; int a = b ?: 1; int C = ({int X=4; X;}); }",
445       Lang_C99, "", Lang_C99, Verifier,
446       traverse(TK_AsIs,
447                functionDecl(hasDescendant(varDecl(
448                    hasName("C"), hasType(asString("int")),
449                    hasInitializer(stmtExpr(
450                        hasAnySubstatement(declStmt(hasSingleDecl(varDecl(
451                            hasName("X"), hasType(asString("int")),
452                            hasInitializer(integerLiteral(equals(4))))))),
453                        hasDescendant(implicitCastExpr()))))))));
454 }
455 
456 TEST_P(ImportExpr, ImportConditionalOperator) {
457   MatchVerifier<Decl> Verifier;
458   testImport("void declToImport() { (void)(true ? 1 : -5); }", Lang_CXX03, "",
459              Lang_CXX03, Verifier,
460              functionDecl(hasDescendant(conditionalOperator(
461                  hasCondition(cxxBoolLiteral(equals(true))),
462                  hasTrueExpression(integerLiteral(equals(1))),
463                  hasFalseExpression(unaryOperator(
464                      hasUnaryOperand(integerLiteral(equals(5)))))))));
465 }
466 
467 TEST_P(ImportExpr, ImportBinaryConditionalOperator) {
468   MatchVerifier<Decl> Verifier;
469   testImport(
470       "void declToImport() { (void)(1 ?: -5); }", Lang_CXX03, "", Lang_CXX03,
471       Verifier,
472       traverse(TK_AsIs,
473                functionDecl(hasDescendant(binaryConditionalOperator(
474                    hasCondition(implicitCastExpr(
475                        hasSourceExpression(opaqueValueExpr(
476                            hasSourceExpression(integerLiteral(equals(1))))),
477                        hasType(booleanType()))),
478                    hasTrueExpression(opaqueValueExpr(
479                        hasSourceExpression(integerLiteral(equals(1))))),
480                    hasFalseExpression(unaryOperator(
481                        hasOperatorName("-"),
482                        hasUnaryOperand(integerLiteral(equals(5))))))))));
483 }
484 
485 TEST_P(ImportExpr, ImportDesignatedInitExpr) {
486   MatchVerifier<Decl> Verifier;
487   testImport(
488       "void declToImport() {"
489       "  struct point { double x; double y; };"
490       "  struct point ptarray[10] = "
491       "{ [2].y = 1.0, [2].x = 2.0, [0].x = 1.0 }; }",
492       Lang_C99, "", Lang_C99, Verifier,
493       functionDecl(hasDescendant(initListExpr(
494           has(designatedInitExpr(designatorCountIs(2),
495                                  hasDescendant(floatLiteral(equals(1.0))),
496                                  hasDescendant(integerLiteral(equals(2))))),
497           has(designatedInitExpr(designatorCountIs(2),
498                                  hasDescendant(floatLiteral(equals(2.0))),
499                                  hasDescendant(integerLiteral(equals(2))))),
500           has(designatedInitExpr(designatorCountIs(2),
501                                  hasDescendant(floatLiteral(equals(1.0))),
502                                  hasDescendant(integerLiteral(equals(0)))))))));
503 }
504 
505 TEST_P(ImportExpr, ImportPredefinedExpr) {
506   MatchVerifier<Decl> Verifier;
507   // __func__ expands as StringLiteral("declToImport")
508   testImport("void declToImport() { (void)__func__; }", Lang_CXX03, "",
509              Lang_CXX03, Verifier,
510              functionDecl(hasDescendant(predefinedExpr(
511                  hasType(asString("const char[13]")),
512                  has(stringLiteral(hasType(asString("const char[13]"))))))));
513 }
514 
515 TEST_P(ImportExpr, ImportInitListExpr) {
516   MatchVerifier<Decl> Verifier;
517   testImport(
518       "void declToImport() {"
519       "  struct point { double x; double y; };"
520       "  point ptarray[10] = { [2].y = 1.0, [2].x = 2.0,"
521       "                        [0].x = 1.0 }; }",
522       Lang_CXX03, "", Lang_CXX03, Verifier,
523       functionDecl(hasDescendant(initListExpr(
524           has(cxxConstructExpr(requiresZeroInitialization())),
525           has(initListExpr(
526               hasType(asString("struct point")), has(floatLiteral(equals(1.0))),
527               has(implicitValueInitExpr(hasType(asString("double")))))),
528           has(initListExpr(hasType(asString("struct point")),
529                            has(floatLiteral(equals(2.0))),
530                            has(floatLiteral(equals(1.0)))))))));
531 }
532 
533 const internal::VariadicDynCastAllOfMatcher<Expr, CXXDefaultInitExpr>
534     cxxDefaultInitExpr;
535 
536 TEST_P(ImportExpr, ImportCXXDefaultInitExpr) {
537   MatchVerifier<Decl> Verifier;
538   testImport("class declToImport { int DefInit = 5; }; declToImport X;",
539              Lang_CXX11, "", Lang_CXX11, Verifier,
540              cxxRecordDecl(hasDescendant(cxxConstructorDecl(
541                  hasAnyConstructorInitializer(cxxCtorInitializer(
542                      withInitializer(cxxDefaultInitExpr())))))));
543   testImport(
544       "struct X { int A = 5; }; X declToImport{};", Lang_CXX17, "", Lang_CXX17,
545       Verifier,
546       varDecl(hasInitializer(initListExpr(hasInit(0, cxxDefaultInitExpr())))));
547 }
548 
549 const internal::VariadicDynCastAllOfMatcher<Expr, VAArgExpr> vaArgExpr;
550 
551 TEST_P(ImportExpr, ImportVAArgExpr) {
552   MatchVerifier<Decl> Verifier;
553   testImport("void declToImport(__builtin_va_list list, ...) {"
554              "  (void)__builtin_va_arg(list, int); }",
555              Lang_CXX03, "", Lang_CXX03, Verifier,
556              functionDecl(hasDescendant(
557                  cStyleCastExpr(hasSourceExpression(vaArgExpr())))));
558 }
559 
560 TEST_P(ImportExpr, CXXTemporaryObjectExpr) {
561   MatchVerifier<Decl> Verifier;
562   testImport(
563       "struct C {};"
564       "void declToImport() { C c = C(); }",
565       Lang_CXX03, "", Lang_CXX03, Verifier,
566       traverse(TK_AsIs,
567                functionDecl(hasDescendant(exprWithCleanups(has(cxxConstructExpr(
568                    has(materializeTemporaryExpr(has(implicitCastExpr(
569                        has(cxxTemporaryObjectExpr()))))))))))));
570 }
571 
572 TEST_P(ImportType, ImportAtomicType) {
573   MatchVerifier<Decl> Verifier;
574   testImport(
575       "void declToImport() { typedef _Atomic(int) a_int; }",
576       Lang_CXX11, "", Lang_CXX11, Verifier,
577       functionDecl(hasDescendant(typedefDecl(has(atomicType())))));
578 }
579 
580 TEST_P(ImportType, ImportUsingType) {
581   MatchVerifier<Decl> Verifier;
582   testImport("struct C {};"
583              "void declToImport() { using ::C; new C{}; }",
584              Lang_CXX11, "", Lang_CXX11, Verifier,
585              functionDecl(hasDescendant(
586                  cxxNewExpr(hasType(pointerType(pointee(usingType())))))));
587 }
588 
589 TEST_P(ImportDecl, ImportFunctionTemplateDecl) {
590   MatchVerifier<Decl> Verifier;
591   testImport("template <typename T> void declToImport() { };", Lang_CXX03, "",
592              Lang_CXX03, Verifier, functionTemplateDecl());
593 }
594 
595 TEST_P(ImportExpr, ImportCXXDependentScopeMemberExpr) {
596   MatchVerifier<Decl> Verifier;
597   testImport("template <typename T> struct C { T t; };"
598              "template <typename T> void declToImport() {"
599              "  C<T> d;"
600              "  (void)d.t;"
601              "}"
602              "void instantiate() { declToImport<int>(); }",
603              Lang_CXX03, "", Lang_CXX03, Verifier,
604              functionTemplateDecl(hasDescendant(
605                  cStyleCastExpr(has(cxxDependentScopeMemberExpr())))));
606   testImport("template <typename T> struct C { T t; };"
607              "template <typename T> void declToImport() {"
608              "  C<T> d;"
609              "  (void)(&d)->t;"
610              "}"
611              "void instantiate() { declToImport<int>(); }",
612              Lang_CXX03, "", Lang_CXX03, Verifier,
613              functionTemplateDecl(hasDescendant(
614                  cStyleCastExpr(has(cxxDependentScopeMemberExpr())))));
615 }
616 
617 TEST_P(ImportType, ImportTypeAliasTemplate) {
618   MatchVerifier<Decl> Verifier;
619   testImport(
620       "template <int K>"
621       "struct dummy { static const int i = K; };"
622       "template <int K> using dummy2 = dummy<K>;"
623       "int declToImport() { return dummy2<3>::i; }",
624       Lang_CXX11, "", Lang_CXX11, Verifier,
625       traverse(TK_AsIs,
626                functionDecl(hasDescendant(implicitCastExpr(has(declRefExpr()))),
627                             unless(hasAncestor(
628                                 translationUnitDecl(has(typeAliasDecl())))))));
629 }
630 
631 const internal::VariadicDynCastAllOfMatcher<Decl, VarTemplateSpecializationDecl>
632     varTemplateSpecializationDecl;
633 
634 TEST_P(ImportDecl, ImportVarTemplate) {
635   MatchVerifier<Decl> Verifier;
636   testImport(
637       "template <typename T>"
638       "T pi = T(3.1415926535897932385L);"
639       "void declToImport() { (void)pi<int>; }",
640       Lang_CXX14, "", Lang_CXX14, Verifier,
641       functionDecl(
642           hasDescendant(declRefExpr(to(varTemplateSpecializationDecl()))),
643           unless(hasAncestor(translationUnitDecl(has(varDecl(
644               hasName("pi"), unless(varTemplateSpecializationDecl()))))))));
645 }
646 
647 TEST_P(ImportType, ImportPackExpansion) {
648   MatchVerifier<Decl> Verifier;
649   testImport("template <typename... Args>"
650              "struct dummy {"
651              "  dummy(Args... args) {}"
652              "  static const int i = 4;"
653              "};"
654              "int declToImport() { return dummy<int>::i; }",
655              Lang_CXX11, "", Lang_CXX11, Verifier,
656              traverse(TK_AsIs, functionDecl(hasDescendant(returnStmt(has(
657                                    implicitCastExpr(has(declRefExpr()))))))));
658 }
659 
660 const internal::VariadicDynCastAllOfMatcher<Type,
661                                             DependentTemplateSpecializationType>
662     dependentTemplateSpecializationType;
663 
664 TEST_P(ImportType, ImportDependentTemplateSpecialization) {
665   MatchVerifier<Decl> Verifier;
666   testImport("template<typename T>"
667              "struct A;"
668              "template<typename T>"
669              "struct declToImport {"
670              "  typename A<T>::template B<T> a;"
671              "};",
672              Lang_CXX03, "", Lang_CXX03, Verifier,
673              classTemplateDecl(has(cxxRecordDecl(has(
674                  fieldDecl(hasType(dependentTemplateSpecializationType())))))));
675 }
676 
677 TEST_P(ImportType, ImportDeducedTemplateSpecialization) {
678   MatchVerifier<Decl> Verifier;
679   testImport("template <typename T>"
680              "class C { public: C(T); };"
681              "C declToImport(123);",
682              Lang_CXX17, "", Lang_CXX17, Verifier,
683              varDecl(hasType(deducedTemplateSpecializationType())));
684 }
685 
686 const internal::VariadicDynCastAllOfMatcher<Stmt, SizeOfPackExpr>
687     sizeOfPackExpr;
688 
689 TEST_P(ImportExpr, ImportSizeOfPackExpr) {
690   MatchVerifier<Decl> Verifier;
691   testImport(
692       "template <typename... Ts>"
693       "void declToImport() {"
694       "  const int i = sizeof...(Ts);"
695       "};"
696       "void g() { declToImport<int>(); }",
697       Lang_CXX11, "", Lang_CXX11, Verifier,
698           functionTemplateDecl(hasDescendant(sizeOfPackExpr())));
699   testImport(
700       "template <typename... Ts>"
701       "using X = int[sizeof...(Ts)];"
702       "template <typename... Us>"
703       "struct Y {"
704       "  X<Us..., int, double, int, Us...> f;"
705       "};"
706       "Y<float, int> declToImport;",
707       Lang_CXX11, "", Lang_CXX11, Verifier,
708       varDecl(hasType(classTemplateSpecializationDecl(has(fieldDecl(hasType(
709           hasUnqualifiedDesugaredType(constantArrayType(hasSize(7))))))))));
710 }
711 
712 const internal::VariadicDynCastAllOfMatcher<Stmt, CXXFoldExpr> cxxFoldExpr;
713 
714 AST_MATCHER_P(CXXFoldExpr, hasOperator, BinaryOperatorKind, Op) {
715   return Node.getOperator() == Op;
716 }
717 AST_MATCHER(CXXFoldExpr, hasInit) { return Node.getInit(); }
718 AST_MATCHER(CXXFoldExpr, isRightFold) { return Node.isRightFold(); }
719 AST_MATCHER(CXXFoldExpr, isLeftFold) { return Node.isLeftFold(); }
720 
721 TEST_P(ImportExpr, ImportCXXFoldExpr) {
722   auto Match1 =
723       cxxFoldExpr(hasOperator(BO_Add), isLeftFold(), unless(hasInit()));
724   auto Match2 = cxxFoldExpr(hasOperator(BO_Sub), isLeftFold(), hasInit());
725   auto Match3 =
726       cxxFoldExpr(hasOperator(BO_Mul), isRightFold(), unless(hasInit()));
727   auto Match4 = cxxFoldExpr(hasOperator(BO_Div), isRightFold(), hasInit());
728 
729   MatchVerifier<Decl> Verifier;
730   testImport("template <typename... Ts>"
731              "void declToImport(Ts... args) {"
732              "  const int i1 = (... + args);"
733              "  const int i2 = (1 - ... - args);"
734              "  const int i3 = (args * ...);"
735              "  const int i4 = (args / ... / 1);"
736              "};"
737              "void g() { declToImport(1, 2, 3, 4, 5); }",
738              Lang_CXX17, "", Lang_CXX17, Verifier,
739              functionTemplateDecl(hasDescendant(Match1), hasDescendant(Match2),
740                                   hasDescendant(Match3),
741                                   hasDescendant(Match4)));
742 }
743 
744 /// \brief Matches __builtin_types_compatible_p:
745 /// GNU extension to check equivalent types
746 /// Given
747 /// \code
748 ///   __builtin_types_compatible_p(int, int)
749 /// \endcode
750 //  will generate TypeTraitExpr <...> 'int'
751 const internal::VariadicDynCastAllOfMatcher<Stmt, TypeTraitExpr> typeTraitExpr;
752 
753 TEST_P(ImportExpr, ImportTypeTraitExpr) {
754   MatchVerifier<Decl> Verifier;
755   testImport(
756       "void declToImport() { "
757       "  (void)__builtin_types_compatible_p(int, int);"
758       "}",
759       Lang_C99, "", Lang_C99, Verifier,
760       functionDecl(hasDescendant(typeTraitExpr(hasType(asString("int"))))));
761 }
762 
763 const internal::VariadicDynCastAllOfMatcher<Stmt, CXXTypeidExpr> cxxTypeidExpr;
764 
765 TEST_P(ImportExpr, ImportCXXTypeidExpr) {
766   MatchVerifier<Decl> Verifier;
767   testImport(
768       "namespace std { class type_info {}; }"
769       "void declToImport() {"
770       "  int x;"
771       "  auto a = typeid(int); auto b = typeid(x);"
772       "}",
773       Lang_CXX11, "", Lang_CXX11, Verifier,
774       traverse(
775           TK_AsIs,
776           functionDecl(
777               hasDescendant(varDecl(hasName("a"), hasInitializer(hasDescendant(
778                                                       cxxTypeidExpr())))),
779               hasDescendant(varDecl(hasName("b"), hasInitializer(hasDescendant(
780                                                       cxxTypeidExpr())))))));
781 }
782 
783 TEST_P(ImportExpr, ImportTypeTraitExprValDep) {
784   MatchVerifier<Decl> Verifier;
785   testImport(
786       "template<typename T> struct declToImport {"
787       "  void m() { (void)__is_pod(T); }"
788       "};"
789       "void f() { declToImport<int>().m(); }",
790       Lang_CXX11, "", Lang_CXX11, Verifier,
791       classTemplateDecl(has(cxxRecordDecl(has(
792           functionDecl(hasDescendant(
793               typeTraitExpr(hasType(booleanType())))))))));
794 }
795 
796 TEST_P(ImportDecl, ImportRecordDeclInFunc) {
797   MatchVerifier<Decl> Verifier;
798   testImport("int declToImport() { "
799              "  struct data_t {int a;int b;};"
800              "  struct data_t d;"
801              "  return 0;"
802              "}",
803              Lang_C99, "", Lang_C99, Verifier,
804              functionDecl(hasBody(compoundStmt(
805                  has(declStmt(hasSingleDecl(varDecl(hasName("d")))))))));
806 }
807 
808 TEST_P(ImportDecl, ImportedVarDeclPreservesThreadLocalStorage) {
809   MatchVerifier<Decl> Verifier;
810   testImport("thread_local int declToImport;", Lang_CXX11, "", Lang_CXX11,
811              Verifier, varDecl(hasThreadStorageDuration()));
812 }
813 
814 TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordTypeInFunc) {
815   Decl *FromTU = getTuDecl("int declToImport() { "
816                            "  struct data_t {int a;int b;};"
817                            "  struct data_t d;"
818                            "  return 0;"
819                            "}",
820                            Lang_C99, "input.c");
821   auto *FromVar =
822       FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("d")));
823   ASSERT_TRUE(FromVar);
824   auto ToType =
825       ImportType(FromVar->getType().getCanonicalType(), FromVar, Lang_C99);
826   EXPECT_FALSE(ToType.isNull());
827 }
828 
829 TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordDeclInFuncParams) {
830   // This construct is not supported by ASTImporter.
831   Decl *FromTU = getTuDecl(
832       "int declToImport(struct data_t{int a;int b;} ***d){ return 0; }",
833       Lang_C99, "input.c");
834   auto *From = FirstDeclMatcher<FunctionDecl>().match(
835       FromTU, functionDecl(hasName("declToImport")));
836   ASSERT_TRUE(From);
837   auto *To = Import(From, Lang_C99);
838   EXPECT_EQ(To, nullptr);
839 }
840 
841 TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordDeclInFuncFromMacro) {
842   Decl *FromTU =
843       getTuDecl("#define NONAME_SIZEOF(type) sizeof(struct{type *dummy;}) \n"
844                 "int declToImport(){ return NONAME_SIZEOF(int); }",
845                 Lang_C99, "input.c");
846   auto *From = FirstDeclMatcher<FunctionDecl>().match(
847       FromTU, functionDecl(hasName("declToImport")));
848   ASSERT_TRUE(From);
849   auto *To = Import(From, Lang_C99);
850   ASSERT_TRUE(To);
851   EXPECT_TRUE(MatchVerifier<FunctionDecl>().match(
852       To, functionDecl(hasName("declToImport"),
853                        hasDescendant(unaryExprOrTypeTraitExpr()))));
854 }
855 
856 TEST_P(ASTImporterOptionSpecificTestBase,
857        ImportRecordDeclInFuncParamsFromMacro) {
858   // This construct is not supported by ASTImporter.
859   Decl *FromTU =
860       getTuDecl("#define PAIR_STRUCT(type) struct data_t{type a;type b;} \n"
861                 "int declToImport(PAIR_STRUCT(int) ***d){ return 0; }",
862                 Lang_C99, "input.c");
863   auto *From = FirstDeclMatcher<FunctionDecl>().match(
864       FromTU, functionDecl(hasName("declToImport")));
865   ASSERT_TRUE(From);
866   auto *To = Import(From, Lang_C99);
867   EXPECT_EQ(To, nullptr);
868 }
869 
870 const internal::VariadicDynCastAllOfMatcher<Expr, CXXPseudoDestructorExpr>
871     cxxPseudoDestructorExpr;
872 
873 TEST_P(ImportExpr, ImportCXXPseudoDestructorExpr) {
874   MatchVerifier<Decl> Verifier;
875   testImport(
876       "typedef int T;"
877       "void declToImport(int *p) {"
878       "  T t;"
879       "  p->T::~T();"
880       "}",
881       Lang_CXX03, "", Lang_CXX03, Verifier,
882       functionDecl(hasDescendant(callExpr(has(cxxPseudoDestructorExpr())))));
883 }
884 
885 TEST_P(ImportDecl, ImportUsingDecl) {
886   MatchVerifier<Decl> Verifier;
887   testImport("namespace foo { int bar; }"
888              "void declToImport() { using foo::bar; }",
889              Lang_CXX03, "", Lang_CXX03, Verifier,
890              functionDecl(hasDescendant(usingDecl(hasName("bar")))));
891 }
892 
893 TEST_P(ImportDecl, ImportUsingTemplate) {
894   MatchVerifier<Decl> Verifier;
895   testImport("namespace ns { template <typename T> struct S {}; }"
896              "template <template <typename> class T> class X {};"
897              "void declToImport() {"
898              "using ns::S;  X<S> xi; }",
899              Lang_CXX11, "", Lang_CXX11, Verifier,
900              functionDecl(
901                  hasDescendant(varDecl(hasTypeLoc(templateSpecializationTypeLoc(
902                      hasAnyTemplateArgumentLoc(templateArgumentLoc())))))));
903 }
904 
905 TEST_P(ImportDecl, ImportUsingEnumDecl) {
906   MatchVerifier<Decl> Verifier;
907   testImport("namespace foo { enum bar { baz, toto, quux }; }"
908              "void declToImport() { using enum foo::bar; }",
909              Lang_CXX20, "", Lang_CXX20, Verifier,
910              functionDecl(hasDescendant(usingEnumDecl(hasName("bar")))));
911 }
912 
913 const internal::VariadicDynCastAllOfMatcher<Decl, UsingPackDecl> usingPackDecl;
914 
915 TEST_P(ImportDecl, ImportUsingPackDecl) {
916   MatchVerifier<Decl> Verifier;
917   testImport(
918       "struct A { int operator()() { return 1; } };"
919       "struct B { int operator()() { return 2; } };"
920       "template<typename ...T> struct C : T... { using T::operator()...; };"
921       "C<A, B> declToImport;",
922       Lang_CXX20, "", Lang_CXX20, Verifier,
923       varDecl(hasType(templateSpecializationType(hasDeclaration(
924           classTemplateSpecializationDecl(hasDescendant(usingPackDecl())))))));
925 }
926 
927 /// \brief Matches shadow declarations introduced into a scope by a
928 ///        (resolved) using declaration.
929 ///
930 /// Given
931 /// \code
932 ///   namespace n { int f; }
933 ///   namespace declToImport { using n::f; }
934 /// \endcode
935 /// usingShadowDecl()
936 ///   matches \code f \endcode
937 const internal::VariadicDynCastAllOfMatcher<Decl,
938                                             UsingShadowDecl> usingShadowDecl;
939 
940 TEST_P(ImportDecl, ImportUsingShadowDecl) {
941   MatchVerifier<Decl> Verifier;
942   // from using-decl
943   testImport("namespace foo { int bar; }"
944              "namespace declToImport { using foo::bar; }",
945              Lang_CXX03, "", Lang_CXX03, Verifier,
946              namespaceDecl(has(usingShadowDecl(hasName("bar")))));
947   // from using-enum-decl
948   testImport("namespace foo { enum bar {baz, toto, quux }; }"
949              "namespace declToImport { using enum foo::bar; }",
950              Lang_CXX20, "", Lang_CXX20, Verifier,
951              namespaceDecl(has(usingShadowDecl(hasName("baz")))));
952 }
953 
954 TEST_P(ImportExpr, ImportUnresolvedLookupExpr) {
955   MatchVerifier<Decl> Verifier;
956   testImport("template<typename T> int foo();"
957              "template <typename T> void declToImport() {"
958              "  (void)::foo<T>;"
959              "  (void)::template foo<T>;"
960              "}"
961              "void instantiate() { declToImport<int>(); }",
962              Lang_CXX03, "", Lang_CXX03, Verifier,
963              functionTemplateDecl(hasDescendant(unresolvedLookupExpr())));
964 }
965 
966 TEST_P(ImportExpr, ImportCXXUnresolvedConstructExpr) {
967   MatchVerifier<Decl> Verifier;
968   testImport("template <typename T> struct C { T t; };"
969              "template <typename T> void declToImport() {"
970              "  C<T> d;"
971              "  d.t = T();"
972              "}"
973              "void instantiate() { declToImport<int>(); }",
974              Lang_CXX03, "", Lang_CXX03, Verifier,
975              functionTemplateDecl(hasDescendant(
976                  binaryOperator(has(cxxUnresolvedConstructExpr())))));
977   testImport("template <typename T> struct C { T t; };"
978              "template <typename T> void declToImport() {"
979              "  C<T> d;"
980              "  (&d)->t = T();"
981              "}"
982              "void instantiate() { declToImport<int>(); }",
983              Lang_CXX03, "", Lang_CXX03, Verifier,
984              functionTemplateDecl(hasDescendant(
985                  binaryOperator(has(cxxUnresolvedConstructExpr())))));
986 }
987 
988 /// Check that function "declToImport()" (which is the templated function
989 /// for corresponding FunctionTemplateDecl) is not added into DeclContext.
990 /// Same for class template declarations.
991 TEST_P(ImportDecl, ImportTemplatedDeclForTemplate) {
992   MatchVerifier<Decl> Verifier;
993   testImport("template <typename T> void declToImport() { T a = 1; }"
994              "void instantiate() { declToImport<int>(); }",
995              Lang_CXX03, "", Lang_CXX03, Verifier,
996              functionTemplateDecl(hasAncestor(translationUnitDecl(
997                  unless(has(functionDecl(hasName("declToImport"))))))));
998   testImport("template <typename T> struct declToImport { T t; };"
999              "void instantiate() { declToImport<int>(); }",
1000              Lang_CXX03, "", Lang_CXX03, Verifier,
1001              classTemplateDecl(hasAncestor(translationUnitDecl(
1002                  unless(has(cxxRecordDecl(hasName("declToImport"))))))));
1003 }
1004 
1005 TEST_P(ImportDecl, ImportClassTemplatePartialSpecialization) {
1006   MatchVerifier<Decl> Verifier;
1007   auto Code =
1008       R"s(
1009       struct declToImport {
1010         template <typename T0> struct X;
1011         template <typename T0> struct X<T0 *> {};
1012       };
1013       )s";
1014   testImport(Code, Lang_CXX03, "", Lang_CXX03, Verifier,
1015              recordDecl(has(classTemplateDecl()),
1016                         has(classTemplateSpecializationDecl())));
1017 }
1018 
1019 TEST_P(ImportExpr, CXXOperatorCallExpr) {
1020   MatchVerifier<Decl> Verifier;
1021   testImport(
1022       "class declToImport {"
1023       "  void f() { *this = declToImport(); }"
1024       "};",
1025       Lang_CXX03, "", Lang_CXX03, Verifier,
1026       cxxRecordDecl(has(cxxMethodDecl(hasDescendant(cxxOperatorCallExpr())))));
1027 }
1028 
1029 TEST_P(ImportExpr, DependentSizedArrayType) {
1030   MatchVerifier<Decl> Verifier;
1031   testImport("template<typename T, int Size> class declToImport {"
1032              "  T data[Size];"
1033              "};",
1034              Lang_CXX03, "", Lang_CXX03, Verifier,
1035              classTemplateDecl(has(cxxRecordDecl(
1036                  has(fieldDecl(hasType(dependentSizedArrayType())))))));
1037 }
1038 
1039 TEST_P(ASTImporterOptionSpecificTestBase, ImportUsingPackDecl) {
1040   Decl *FromTU = getTuDecl(
1041       "struct A { int operator()() { return 1; } };"
1042       "struct B { int operator()() { return 2; } };"
1043       "template<typename ...T> struct C : T... { using T::operator()...; };"
1044       "C<A, B> Var;",
1045       Lang_CXX20);
1046 
1047   auto From = FirstDeclMatcher<UsingPackDecl>().match(FromTU, usingPackDecl());
1048   ASSERT_TRUE(From);
1049   auto To = cast<UsingPackDecl>(Import(From, Lang_CXX20));
1050   ASSERT_TRUE(To);
1051 
1052   ArrayRef<NamedDecl *> FromExpansions = From->expansions();
1053   ArrayRef<NamedDecl *> ToExpansions = To->expansions();
1054   ASSERT_EQ(FromExpansions.size(), ToExpansions.size());
1055   for (unsigned int I = 0; I < FromExpansions.size(); ++I) {
1056     auto ImportedExpansion = Import(FromExpansions[I], Lang_CXX20);
1057     EXPECT_EQ(ImportedExpansion, ToExpansions[I]);
1058   }
1059 
1060   auto ImportedDC = cast<Decl>(Import(From->getDeclContext(), Lang_CXX20));
1061   EXPECT_EQ(ImportedDC, cast<Decl>(To->getDeclContext()));
1062 }
1063 
1064 TEST_P(ASTImporterOptionSpecificTestBase, TemplateTypeParmDeclNoDefaultArg) {
1065   Decl *FromTU = getTuDecl("template<typename T> struct X {};", Lang_CXX03);
1066   auto From = FirstDeclMatcher<TemplateTypeParmDecl>().match(
1067       FromTU, templateTypeParmDecl(hasName("T")));
1068   TemplateTypeParmDecl *To = Import(From, Lang_CXX03);
1069   ASSERT_FALSE(To->hasDefaultArgument());
1070 }
1071 
1072 TEST_P(ASTImporterOptionSpecificTestBase, TemplateTypeParmDeclDefaultArg) {
1073   Decl *FromTU =
1074       getTuDecl("template<typename T = int> struct X {};", Lang_CXX03);
1075   auto From = FirstDeclMatcher<TemplateTypeParmDecl>().match(
1076       FromTU, templateTypeParmDecl(hasName("T")));
1077   TemplateTypeParmDecl *To = Import(From, Lang_CXX03);
1078   ASSERT_TRUE(To->hasDefaultArgument());
1079   QualType ToArg = To->getDefaultArgument();
1080   ASSERT_EQ(ToArg, QualType(To->getASTContext().IntTy));
1081 }
1082 
1083 TEST_P(ASTImporterOptionSpecificTestBase, ImportBeginLocOfDeclRefExpr) {
1084   Decl *FromTU =
1085       getTuDecl("class A { public: static int X; }; void f() { (void)A::X; }",
1086                 Lang_CXX03);
1087   auto From = FirstDeclMatcher<FunctionDecl>().match(
1088       FromTU, functionDecl(hasName("f")));
1089   ASSERT_TRUE(From);
1090   ASSERT_TRUE(
1091       cast<CStyleCastExpr>(cast<CompoundStmt>(From->getBody())->body_front())
1092           ->getSubExpr()
1093           ->getBeginLoc()
1094           .isValid());
1095   FunctionDecl *To = Import(From, Lang_CXX03);
1096   ASSERT_TRUE(To);
1097   ASSERT_TRUE(
1098       cast<CStyleCastExpr>(cast<CompoundStmt>(To->getBody())->body_front())
1099           ->getSubExpr()
1100           ->getBeginLoc()
1101           .isValid());
1102 }
1103 
1104 TEST_P(ASTImporterOptionSpecificTestBase,
1105        TemplateTemplateParmDeclNoDefaultArg) {
1106   Decl *FromTU = getTuDecl(R"(
1107                            template<template<typename> typename TT> struct Y {};
1108                            )",
1109                            Lang_CXX17);
1110   auto From = FirstDeclMatcher<TemplateTemplateParmDecl>().match(
1111       FromTU, templateTemplateParmDecl(hasName("TT")));
1112   TemplateTemplateParmDecl *To = Import(From, Lang_CXX17);
1113   ASSERT_FALSE(To->hasDefaultArgument());
1114 }
1115 
1116 TEST_P(ASTImporterOptionSpecificTestBase, TemplateTemplateParmDeclDefaultArg) {
1117   Decl *FromTU = getTuDecl(R"(
1118                            template<typename T> struct X {};
1119                            template<template<typename> typename TT = X> struct Y {};
1120                            )",
1121                            Lang_CXX17);
1122   auto From = FirstDeclMatcher<TemplateTemplateParmDecl>().match(
1123       FromTU, templateTemplateParmDecl(hasName("TT")));
1124   TemplateTemplateParmDecl *To = Import(From, Lang_CXX17);
1125   ASSERT_TRUE(To->hasDefaultArgument());
1126   const TemplateArgument &ToDefaultArg = To->getDefaultArgument().getArgument();
1127   ASSERT_TRUE(To->isTemplateDecl());
1128   TemplateDecl *ToTemplate = ToDefaultArg.getAsTemplate().getAsTemplateDecl();
1129 
1130   // Find the default argument template 'X' in the AST and compare it against
1131   // the default argument we got.
1132   auto ToExpectedDecl = FirstDeclMatcher<ClassTemplateDecl>().match(
1133       To->getTranslationUnitDecl(), classTemplateDecl(hasName("X")));
1134   ASSERT_EQ(ToTemplate, ToExpectedDecl);
1135 }
1136 
1137 TEST_P(ASTImporterOptionSpecificTestBase, NonTypeTemplateParmDeclNoDefaultArg) {
1138   Decl *FromTU = getTuDecl("template<int N> struct X {};", Lang_CXX03);
1139   auto From = FirstDeclMatcher<NonTypeTemplateParmDecl>().match(
1140       FromTU, nonTypeTemplateParmDecl(hasName("N")));
1141   NonTypeTemplateParmDecl *To = Import(From, Lang_CXX03);
1142   ASSERT_FALSE(To->hasDefaultArgument());
1143 }
1144 
1145 TEST_P(ASTImporterOptionSpecificTestBase, NonTypeTemplateParmDeclDefaultArg) {
1146   Decl *FromTU = getTuDecl("template<int S = 1> struct X {};", Lang_CXX03);
1147   auto From = FirstDeclMatcher<NonTypeTemplateParmDecl>().match(
1148       FromTU, nonTypeTemplateParmDecl(hasName("S")));
1149   NonTypeTemplateParmDecl *To = Import(From, Lang_CXX03);
1150   ASSERT_TRUE(To->hasDefaultArgument());
1151   Stmt *ToArg = To->getDefaultArgument();
1152   ASSERT_TRUE(isa<ConstantExpr>(ToArg));
1153   ToArg = *ToArg->child_begin();
1154   ASSERT_TRUE(isa<IntegerLiteral>(ToArg));
1155   ASSERT_EQ(cast<IntegerLiteral>(ToArg)->getValue().getLimitedValue(), 1U);
1156 }
1157 
1158 TEST_P(ASTImporterOptionSpecificTestBase,
1159        ImportOfTemplatedDeclOfClassTemplateDecl) {
1160   Decl *FromTU = getTuDecl("template<class X> struct S{};", Lang_CXX03);
1161   auto From =
1162       FirstDeclMatcher<ClassTemplateDecl>().match(FromTU, classTemplateDecl());
1163   ASSERT_TRUE(From);
1164   auto To = cast<ClassTemplateDecl>(Import(From, Lang_CXX03));
1165   ASSERT_TRUE(To);
1166   Decl *ToTemplated = To->getTemplatedDecl();
1167   Decl *ToTemplated1 = Import(From->getTemplatedDecl(), Lang_CXX03);
1168   EXPECT_TRUE(ToTemplated1);
1169   EXPECT_EQ(ToTemplated1, ToTemplated);
1170 }
1171 
1172 TEST_P(ASTImporterOptionSpecificTestBase,
1173        ImportOfTemplatedDeclOfFunctionTemplateDecl) {
1174   Decl *FromTU = getTuDecl("template<class X> void f(){}", Lang_CXX03);
1175   auto From = FirstDeclMatcher<FunctionTemplateDecl>().match(
1176       FromTU, functionTemplateDecl());
1177   ASSERT_TRUE(From);
1178   auto To = cast<FunctionTemplateDecl>(Import(From, Lang_CXX03));
1179   ASSERT_TRUE(To);
1180   Decl *ToTemplated = To->getTemplatedDecl();
1181   Decl *ToTemplated1 = Import(From->getTemplatedDecl(), Lang_CXX03);
1182   EXPECT_TRUE(ToTemplated1);
1183   EXPECT_EQ(ToTemplated1, ToTemplated);
1184 }
1185 
1186 TEST_P(ASTImporterOptionSpecificTestBase,
1187        ImportOfTemplatedDeclShouldImportTheClassTemplateDecl) {
1188   Decl *FromTU = getTuDecl("template<class X> struct S{};", Lang_CXX03);
1189   auto FromFT =
1190       FirstDeclMatcher<ClassTemplateDecl>().match(FromTU, classTemplateDecl());
1191   ASSERT_TRUE(FromFT);
1192 
1193   auto ToTemplated =
1194       cast<CXXRecordDecl>(Import(FromFT->getTemplatedDecl(), Lang_CXX03));
1195   EXPECT_TRUE(ToTemplated);
1196   auto ToTU = ToTemplated->getTranslationUnitDecl();
1197   auto ToFT =
1198       FirstDeclMatcher<ClassTemplateDecl>().match(ToTU, classTemplateDecl());
1199   EXPECT_TRUE(ToFT);
1200 }
1201 
1202 TEST_P(ASTImporterOptionSpecificTestBase,
1203        ImportOfTemplatedDeclShouldImportTheFunctionTemplateDecl) {
1204   Decl *FromTU = getTuDecl("template<class X> void f(){}", Lang_CXX03);
1205   auto FromFT = FirstDeclMatcher<FunctionTemplateDecl>().match(
1206       FromTU, functionTemplateDecl());
1207   ASSERT_TRUE(FromFT);
1208 
1209   auto ToTemplated =
1210       cast<FunctionDecl>(Import(FromFT->getTemplatedDecl(), Lang_CXX03));
1211   EXPECT_TRUE(ToTemplated);
1212   auto ToTU = ToTemplated->getTranslationUnitDecl();
1213   auto ToFT = FirstDeclMatcher<FunctionTemplateDecl>().match(
1214       ToTU, functionTemplateDecl());
1215   EXPECT_TRUE(ToFT);
1216 }
1217 
1218 TEST_P(ASTImporterOptionSpecificTestBase, ImportCorrectTemplatedDecl) {
1219   auto Code =
1220         R"(
1221         namespace x {
1222           template<class X> struct S1{};
1223           template<class X> struct S2{};
1224           template<class X> struct S3{};
1225         }
1226         )";
1227   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
1228   auto FromNs =
1229       FirstDeclMatcher<NamespaceDecl>().match(FromTU, namespaceDecl());
1230   auto ToNs = cast<NamespaceDecl>(Import(FromNs, Lang_CXX03));
1231   ASSERT_TRUE(ToNs);
1232   auto From =
1233       FirstDeclMatcher<ClassTemplateDecl>().match(FromTU,
1234                                                   classTemplateDecl(
1235                                                       hasName("S2")));
1236   auto To =
1237       FirstDeclMatcher<ClassTemplateDecl>().match(ToNs,
1238                                                   classTemplateDecl(
1239                                                       hasName("S2")));
1240   ASSERT_TRUE(From);
1241   ASSERT_TRUE(To);
1242   auto ToTemplated = To->getTemplatedDecl();
1243   auto ToTemplated1 =
1244       cast<CXXRecordDecl>(Import(From->getTemplatedDecl(), Lang_CXX03));
1245   EXPECT_TRUE(ToTemplated1);
1246   ASSERT_EQ(ToTemplated1, ToTemplated);
1247 }
1248 
1249 TEST_P(ASTImporterOptionSpecificTestBase, ImportChooseExpr) {
1250   // This tests the import of isConditionTrue directly to make sure the importer
1251   // gets it right.
1252   Decl *From, *To;
1253   std::tie(From, To) = getImportedDecl(
1254       "void declToImport() { (void)__builtin_choose_expr(1, 0, 1); }", Lang_C99,
1255       "", Lang_C99);
1256 
1257   auto ToResults = match(chooseExpr().bind("choose"), To->getASTContext());
1258   auto FromResults = match(chooseExpr().bind("choose"), From->getASTContext());
1259 
1260   const ChooseExpr *FromChooseExpr =
1261       selectFirst<ChooseExpr>("choose", FromResults);
1262   ASSERT_TRUE(FromChooseExpr);
1263 
1264   const ChooseExpr *ToChooseExpr = selectFirst<ChooseExpr>("choose", ToResults);
1265   ASSERT_TRUE(ToChooseExpr);
1266 
1267   EXPECT_EQ(FromChooseExpr->isConditionTrue(), ToChooseExpr->isConditionTrue());
1268   EXPECT_EQ(FromChooseExpr->isConditionDependent(),
1269             ToChooseExpr->isConditionDependent());
1270 }
1271 
1272 TEST_P(ASTImporterOptionSpecificTestBase, ImportGenericSelectionExpr) {
1273   Decl *From, *To;
1274   std::tie(From, To) = getImportedDecl(
1275       R"(
1276       int declToImport() {
1277         int x;
1278         return _Generic(x, int: 0, default: 1);
1279       }
1280       )",
1281       Lang_C99, "", Lang_C99);
1282 
1283   auto ToResults =
1284       match(genericSelectionExpr().bind("expr"), To->getASTContext());
1285   auto FromResults =
1286       match(genericSelectionExpr().bind("expr"), From->getASTContext());
1287 
1288   const GenericSelectionExpr *FromGenericSelectionExpr =
1289       selectFirst<GenericSelectionExpr>("expr", FromResults);
1290   ASSERT_TRUE(FromGenericSelectionExpr);
1291 
1292   const GenericSelectionExpr *ToGenericSelectionExpr =
1293       selectFirst<GenericSelectionExpr>("expr", ToResults);
1294   ASSERT_TRUE(ToGenericSelectionExpr);
1295 
1296   EXPECT_EQ(FromGenericSelectionExpr->isResultDependent(),
1297             ToGenericSelectionExpr->isResultDependent());
1298   EXPECT_EQ(FromGenericSelectionExpr->getResultIndex(),
1299             ToGenericSelectionExpr->getResultIndex());
1300 }
1301 
1302 TEST_P(ASTImporterOptionSpecificTestBase,
1303        ImportFunctionWithBackReferringParameter) {
1304   Decl *From, *To;
1305   std::tie(From, To) = getImportedDecl(
1306       R"(
1307       template <typename T> struct X {};
1308 
1309       void declToImport(int y, X<int> &x) {}
1310 
1311       template <> struct X<int> {
1312         void g() {
1313           X<int> x;
1314           declToImport(0, x);
1315         }
1316       };
1317       )",
1318       Lang_CXX03, "", Lang_CXX03);
1319 
1320   MatchVerifier<Decl> Verifier;
1321   auto Matcher = functionDecl(hasName("declToImport"),
1322                               parameterCountIs(2),
1323                               hasParameter(0, hasName("y")),
1324                               hasParameter(1, hasName("x")),
1325                               hasParameter(1, hasType(asString("X<int> &"))));
1326   ASSERT_TRUE(Verifier.match(From, Matcher));
1327   EXPECT_TRUE(Verifier.match(To, Matcher));
1328 }
1329 
1330 TEST_P(ASTImporterOptionSpecificTestBase,
1331        TUshouldNotContainTemplatedDeclOfFunctionTemplates) {
1332   Decl *From, *To;
1333   std::tie(From, To) =
1334       getImportedDecl("template <typename T> void declToImport() { T a = 1; }"
1335                       "void instantiate() { declToImport<int>(); }",
1336                       Lang_CXX03, "", Lang_CXX03);
1337 
1338   auto Check = [](Decl *D) -> bool {
1339     auto TU = D->getTranslationUnitDecl();
1340     for (auto Child : TU->decls()) {
1341       if (auto *FD = dyn_cast<FunctionDecl>(Child)) {
1342         if (FD->getNameAsString() == "declToImport") {
1343           GTEST_NONFATAL_FAILURE_(
1344               "TU should not contain any FunctionDecl with name declToImport");
1345           return false;
1346         }
1347       }
1348     }
1349     return true;
1350   };
1351 
1352   ASSERT_TRUE(Check(From));
1353   EXPECT_TRUE(Check(To));
1354 }
1355 
1356 TEST_P(ASTImporterOptionSpecificTestBase,
1357        TUshouldNotContainTemplatedDeclOfClassTemplates) {
1358   Decl *From, *To;
1359   std::tie(From, To) =
1360       getImportedDecl("template <typename T> struct declToImport { T t; };"
1361                       "void instantiate() { declToImport<int>(); }",
1362                       Lang_CXX03, "", Lang_CXX03);
1363 
1364   auto Check = [](Decl *D) -> bool {
1365     auto TU = D->getTranslationUnitDecl();
1366     for (auto Child : TU->decls()) {
1367       if (auto *RD = dyn_cast<CXXRecordDecl>(Child)) {
1368         if (RD->getNameAsString() == "declToImport") {
1369           GTEST_NONFATAL_FAILURE_(
1370               "TU should not contain any CXXRecordDecl with name declToImport");
1371           return false;
1372         }
1373       }
1374     }
1375     return true;
1376   };
1377 
1378   ASSERT_TRUE(Check(From));
1379   EXPECT_TRUE(Check(To));
1380 }
1381 
1382 TEST_P(ASTImporterOptionSpecificTestBase,
1383        TUshouldNotContainTemplatedDeclOfTypeAlias) {
1384   Decl *From, *To;
1385   std::tie(From, To) =
1386       getImportedDecl(
1387           "template <typename T> struct X {};"
1388           "template <typename T> using declToImport = X<T>;"
1389           "void instantiate() { declToImport<int> a; }",
1390                       Lang_CXX11, "", Lang_CXX11);
1391 
1392   auto Check = [](Decl *D) -> bool {
1393     auto TU = D->getTranslationUnitDecl();
1394     for (auto Child : TU->decls()) {
1395       if (auto *AD = dyn_cast<TypeAliasDecl>(Child)) {
1396         if (AD->getNameAsString() == "declToImport") {
1397           GTEST_NONFATAL_FAILURE_(
1398               "TU should not contain any TypeAliasDecl with name declToImport");
1399           return false;
1400         }
1401       }
1402     }
1403     return true;
1404   };
1405 
1406   ASSERT_TRUE(Check(From));
1407   EXPECT_TRUE(Check(To));
1408 }
1409 
1410 TEST_P(ASTImporterOptionSpecificTestBase,
1411        TUshouldNotContainClassTemplateSpecializationOfImplicitInstantiation) {
1412 
1413   Decl *From, *To;
1414   std::tie(From, To) = getImportedDecl(
1415       R"(
1416       template<class T>
1417       class Base {};
1418       class declToImport : public Base<declToImport> {};
1419       )",
1420       Lang_CXX03, "", Lang_CXX03);
1421 
1422   // Check that the ClassTemplateSpecializationDecl is NOT the child of the TU.
1423   auto Pattern =
1424       translationUnitDecl(unless(has(classTemplateSpecializationDecl())));
1425   ASSERT_TRUE(
1426       MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
1427   EXPECT_TRUE(
1428       MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
1429 
1430   // Check that the ClassTemplateSpecializationDecl is the child of the
1431   // ClassTemplateDecl.
1432   Pattern = translationUnitDecl(has(classTemplateDecl(
1433       hasName("Base"), has(classTemplateSpecializationDecl()))));
1434   ASSERT_TRUE(
1435       MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
1436   EXPECT_TRUE(
1437       MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
1438 }
1439 
1440 AST_MATCHER_P(RecordDecl, hasFieldOrder, std::vector<StringRef>, Order) {
1441   size_t Index = 0;
1442   for (Decl *D : Node.decls()) {
1443     if (isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) {
1444       auto *ND = cast<NamedDecl>(D);
1445       if (Index == Order.size())
1446         return false;
1447       if (ND->getName() != Order[Index])
1448         return false;
1449       ++Index;
1450     }
1451   }
1452   return Index == Order.size();
1453 }
1454 
1455 TEST_P(ASTImporterOptionSpecificTestBase,
1456        TUshouldContainClassTemplateSpecializationOfExplicitInstantiation) {
1457   Decl *From, *To;
1458   std::tie(From, To) = getImportedDecl(
1459       R"(
1460       namespace NS {
1461         template<class T>
1462         class X {};
1463         template class X<int>;
1464       }
1465       )",
1466       Lang_CXX03, "", Lang_CXX03, "NS");
1467 
1468   // Check that the ClassTemplateSpecializationDecl is NOT the child of the
1469   // ClassTemplateDecl.
1470   auto Pattern = namespaceDecl(has(classTemplateDecl(
1471       hasName("X"), unless(has(classTemplateSpecializationDecl())))));
1472   ASSERT_TRUE(MatchVerifier<Decl>{}.match(From, Pattern));
1473   EXPECT_TRUE(MatchVerifier<Decl>{}.match(To, Pattern));
1474 
1475   // Check that the ClassTemplateSpecializationDecl is the child of the
1476   // NamespaceDecl.
1477   Pattern = namespaceDecl(has(classTemplateSpecializationDecl(hasName("X"))));
1478   ASSERT_TRUE(MatchVerifier<Decl>{}.match(From, Pattern));
1479   EXPECT_TRUE(MatchVerifier<Decl>{}.match(To, Pattern));
1480 }
1481 
1482 TEST_P(ASTImporterOptionSpecificTestBase,
1483        CXXRecordDeclFieldsShouldBeInCorrectOrder) {
1484   Decl *From, *To;
1485   std::tie(From, To) =
1486       getImportedDecl(
1487           "struct declToImport { int a; int b; };",
1488                       Lang_CXX11, "", Lang_CXX11);
1489 
1490   MatchVerifier<Decl> Verifier;
1491   ASSERT_TRUE(Verifier.match(From, cxxRecordDecl(hasFieldOrder({"a", "b"}))));
1492   EXPECT_TRUE(Verifier.match(To, cxxRecordDecl(hasFieldOrder({"a", "b"}))));
1493 }
1494 
1495 TEST_P(ASTImporterOptionSpecificTestBase,
1496        CXXRecordDeclFieldOrderShouldNotDependOnImportOrder) {
1497   Decl *From, *To;
1498   std::tie(From, To) = getImportedDecl(
1499       // The original recursive algorithm of ASTImporter first imports 'c' then
1500       // 'b' and lastly 'a'.  Therefore we must restore the order somehow.
1501       R"s(
1502       struct declToImport {
1503           int a = c + b;
1504           int b = 1;
1505           int c = 2;
1506       };
1507       )s",
1508       Lang_CXX11, "", Lang_CXX11);
1509 
1510   MatchVerifier<Decl> Verifier;
1511   ASSERT_TRUE(
1512       Verifier.match(From, cxxRecordDecl(hasFieldOrder({"a", "b", "c"}))));
1513   EXPECT_TRUE(
1514       Verifier.match(To, cxxRecordDecl(hasFieldOrder({"a", "b", "c"}))));
1515 }
1516 
1517 TEST_P(ASTImporterOptionSpecificTestBase,
1518        CXXRecordDeclFieldAndIndirectFieldOrder) {
1519   Decl *From, *To;
1520   std::tie(From, To) = getImportedDecl(
1521       // First field is "a", then the field for unnamed union, then "b" and "c"
1522       // from it (indirect fields), then "d".
1523       R"s(
1524       struct declToImport {
1525         int a = d;
1526         union {
1527           int b;
1528           int c;
1529         };
1530         int d;
1531       };
1532       )s",
1533       Lang_CXX11, "", Lang_CXX11);
1534 
1535   MatchVerifier<Decl> Verifier;
1536   ASSERT_TRUE(Verifier.match(
1537       From, cxxRecordDecl(hasFieldOrder({"a", "", "b", "c", "d"}))));
1538   EXPECT_TRUE(Verifier.match(
1539       To, cxxRecordDecl(hasFieldOrder({"a", "", "b", "c", "d"}))));
1540 }
1541 
1542 TEST_P(ASTImporterOptionSpecificTestBase, ShouldImportImplicitCXXRecordDecl) {
1543   Decl *From, *To;
1544   std::tie(From, To) = getImportedDecl(
1545       R"(
1546       struct declToImport {
1547       };
1548       )",
1549       Lang_CXX03, "", Lang_CXX03);
1550 
1551   MatchVerifier<Decl> Verifier;
1552   // Match the implicit Decl.
1553   auto Matcher = cxxRecordDecl(has(cxxRecordDecl()));
1554   ASSERT_TRUE(Verifier.match(From, Matcher));
1555   EXPECT_TRUE(Verifier.match(To, Matcher));
1556 }
1557 
1558 TEST_P(ASTImporterOptionSpecificTestBase,
1559        ShouldImportImplicitCXXRecordDeclOfClassTemplate) {
1560   Decl *From, *To;
1561   std::tie(From, To) = getImportedDecl(
1562       R"(
1563       template <typename U>
1564       struct declToImport {
1565       };
1566       )",
1567       Lang_CXX03, "", Lang_CXX03);
1568 
1569   MatchVerifier<Decl> Verifier;
1570   // Match the implicit Decl.
1571   auto Matcher = classTemplateDecl(has(cxxRecordDecl(has(cxxRecordDecl()))));
1572   ASSERT_TRUE(Verifier.match(From, Matcher));
1573   EXPECT_TRUE(Verifier.match(To, Matcher));
1574 }
1575 
1576 TEST_P(ASTImporterOptionSpecificTestBase,
1577        ShouldImportImplicitCXXRecordDeclOfClassTemplateSpecializationDecl) {
1578   Decl *From, *To;
1579   std::tie(From, To) = getImportedDecl(
1580       R"(
1581       template<class T>
1582       class Base {};
1583       class declToImport : public Base<declToImport> {};
1584       )",
1585       Lang_CXX03, "", Lang_CXX03);
1586 
1587   auto hasImplicitClass = has(cxxRecordDecl());
1588   auto Pattern = translationUnitDecl(has(classTemplateDecl(
1589       hasName("Base"),
1590       has(classTemplateSpecializationDecl(hasImplicitClass)))));
1591   ASSERT_TRUE(
1592       MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
1593   EXPECT_TRUE(
1594       MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
1595 }
1596 
1597 TEST_P(ASTImporterOptionSpecificTestBase, IDNSOrdinary) {
1598   Decl *From, *To;
1599   std::tie(From, To) =
1600       getImportedDecl("void declToImport() {}", Lang_CXX03, "", Lang_CXX03);
1601 
1602   MatchVerifier<Decl> Verifier;
1603   auto Matcher = functionDecl();
1604   ASSERT_TRUE(Verifier.match(From, Matcher));
1605   EXPECT_TRUE(Verifier.match(To, Matcher));
1606   EXPECT_EQ(From->getIdentifierNamespace(), To->getIdentifierNamespace());
1607 }
1608 
1609 TEST_P(ASTImporterOptionSpecificTestBase, IDNSOfNonmemberOperator) {
1610   Decl *FromTU = getTuDecl(
1611       R"(
1612       struct X {};
1613       void operator<<(int, X);
1614       )",
1615       Lang_CXX03);
1616   Decl *From = LastDeclMatcher<Decl>{}.match(FromTU, functionDecl());
1617   const Decl *To = Import(From, Lang_CXX03);
1618   EXPECT_EQ(From->getIdentifierNamespace(), To->getIdentifierNamespace());
1619 }
1620 
1621 TEST_P(ASTImporterOptionSpecificTestBase,
1622        ShouldImportMembersOfClassTemplateSpecializationDecl) {
1623   Decl *From, *To;
1624   std::tie(From, To) = getImportedDecl(
1625       R"(
1626       template<class T>
1627       class Base { int a; };
1628       class declToImport : Base<declToImport> {};
1629       )",
1630       Lang_CXX03, "", Lang_CXX03);
1631 
1632   auto Pattern = translationUnitDecl(has(classTemplateDecl(
1633       hasName("Base"),
1634       has(classTemplateSpecializationDecl(has(fieldDecl(hasName("a"))))))));
1635   ASSERT_TRUE(
1636       MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
1637   EXPECT_TRUE(
1638       MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
1639 }
1640 
1641 TEST_P(ASTImporterOptionSpecificTestBase,
1642        ImportDefinitionOfClassTemplateAfterFwdDecl) {
1643   {
1644     Decl *FromTU = getTuDecl(
1645         R"(
1646             template <typename T>
1647             struct B;
1648             )",
1649         Lang_CXX03, "input0.cc");
1650     auto *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
1651         FromTU, classTemplateDecl(hasName("B")));
1652 
1653     Import(FromD, Lang_CXX03);
1654   }
1655 
1656   {
1657     Decl *FromTU = getTuDecl(
1658         R"(
1659             template <typename T>
1660             struct B {
1661               void f();
1662             };
1663             )",
1664         Lang_CXX03, "input1.cc");
1665     FunctionDecl *FromD = FirstDeclMatcher<FunctionDecl>().match(
1666         FromTU, functionDecl(hasName("f")));
1667     Import(FromD, Lang_CXX03);
1668     auto *FromCTD = FirstDeclMatcher<ClassTemplateDecl>().match(
1669         FromTU, classTemplateDecl(hasName("B")));
1670     auto *ToCTD = cast<ClassTemplateDecl>(Import(FromCTD, Lang_CXX03));
1671     EXPECT_TRUE(ToCTD->isThisDeclarationADefinition());
1672   }
1673 }
1674 
1675 TEST_P(ASTImporterOptionSpecificTestBase,
1676        ImportDefinitionOfClassTemplateIfThereIsAnExistingFwdDeclAndDefinition) {
1677   Decl *ToTU = getToTuDecl(
1678       R"(
1679       template <typename T>
1680       struct B {
1681         void f();
1682       };
1683 
1684       template <typename T>
1685       struct B;
1686       )",
1687       Lang_CXX03);
1688   ASSERT_EQ(1u, DeclCounterWithPredicate<ClassTemplateDecl>(
1689                     [](const ClassTemplateDecl *T) {
1690                       return T->isThisDeclarationADefinition();
1691                     })
1692                     .match(ToTU, classTemplateDecl()));
1693 
1694   Decl *FromTU = getTuDecl(
1695       R"(
1696       template <typename T>
1697       struct B {
1698         void f();
1699       };
1700       )",
1701       Lang_CXX03, "input1.cc");
1702   ClassTemplateDecl *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
1703       FromTU, classTemplateDecl(hasName("B")));
1704 
1705   Import(FromD, Lang_CXX03);
1706 
1707   // We should have only one definition.
1708   EXPECT_EQ(1u, DeclCounterWithPredicate<ClassTemplateDecl>(
1709                     [](const ClassTemplateDecl *T) {
1710                       return T->isThisDeclarationADefinition();
1711                     })
1712                     .match(ToTU, classTemplateDecl()));
1713 }
1714 
1715 TEST_P(ASTImporterOptionSpecificTestBase,
1716        ImportDefinitionOfClassIfThereIsAnExistingFwdDeclAndDefinition) {
1717   Decl *ToTU = getToTuDecl(
1718       R"(
1719       struct B {
1720         void f();
1721       };
1722 
1723       struct B;
1724       )",
1725       Lang_CXX03);
1726   ASSERT_EQ(2u, DeclCounter<CXXRecordDecl>().match(
1727                     ToTU, cxxRecordDecl(unless(isImplicit()))));
1728 
1729   Decl *FromTU = getTuDecl(
1730       R"(
1731       struct B {
1732         void f();
1733       };
1734       )",
1735       Lang_CXX03, "input1.cc");
1736   auto *FromD = FirstDeclMatcher<CXXRecordDecl>().match(
1737       FromTU, cxxRecordDecl(hasName("B")));
1738 
1739   Import(FromD, Lang_CXX03);
1740 
1741   EXPECT_EQ(2u, DeclCounter<CXXRecordDecl>().match(
1742                     ToTU, cxxRecordDecl(unless(isImplicit()))));
1743 }
1744 
1745 static void CompareSourceLocs(FullSourceLoc Loc1, FullSourceLoc Loc2) {
1746   EXPECT_EQ(Loc1.getExpansionLineNumber(), Loc2.getExpansionLineNumber());
1747   EXPECT_EQ(Loc1.getExpansionColumnNumber(), Loc2.getExpansionColumnNumber());
1748   EXPECT_EQ(Loc1.getSpellingLineNumber(), Loc2.getSpellingLineNumber());
1749   EXPECT_EQ(Loc1.getSpellingColumnNumber(), Loc2.getSpellingColumnNumber());
1750 }
1751 static void CompareSourceRanges(SourceRange Range1, SourceRange Range2,
1752                                 SourceManager &SM1, SourceManager &SM2) {
1753   CompareSourceLocs(FullSourceLoc{ Range1.getBegin(), SM1 },
1754                     FullSourceLoc{ Range2.getBegin(), SM2 });
1755   CompareSourceLocs(FullSourceLoc{ Range1.getEnd(), SM1 },
1756                     FullSourceLoc{ Range2.getEnd(), SM2 });
1757 }
1758 TEST_P(ASTImporterOptionSpecificTestBase, ImportSourceLocs) {
1759   Decl *FromTU = getTuDecl(
1760       R"(
1761       #define MFOO(arg) arg = arg + 1
1762 
1763       void foo() {
1764         int a = 5;
1765         MFOO(a);
1766       }
1767       )",
1768       Lang_CXX03);
1769   auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
1770   auto ToD = Import(FromD, Lang_CXX03);
1771 
1772   auto ToLHS = LastDeclMatcher<DeclRefExpr>().match(ToD, declRefExpr());
1773   auto FromLHS = LastDeclMatcher<DeclRefExpr>().match(FromTU, declRefExpr());
1774   auto ToRHS = LastDeclMatcher<IntegerLiteral>().match(ToD, integerLiteral());
1775   auto FromRHS =
1776       LastDeclMatcher<IntegerLiteral>().match(FromTU, integerLiteral());
1777 
1778   SourceManager &ToSM = ToAST->getASTContext().getSourceManager();
1779   SourceManager &FromSM = FromD->getASTContext().getSourceManager();
1780   CompareSourceRanges(ToD->getSourceRange(), FromD->getSourceRange(), ToSM,
1781                       FromSM);
1782   CompareSourceRanges(ToLHS->getSourceRange(), FromLHS->getSourceRange(), ToSM,
1783                       FromSM);
1784   CompareSourceRanges(ToRHS->getSourceRange(), FromRHS->getSourceRange(), ToSM,
1785                       FromSM);
1786 }
1787 
1788 TEST_P(ASTImporterOptionSpecificTestBase, ImportNestedMacro) {
1789   Decl *FromTU = getTuDecl(
1790       R"(
1791       #define FUNC_INT void declToImport
1792       #define FUNC FUNC_INT
1793       FUNC(int a);
1794       )",
1795       Lang_CXX03);
1796   auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
1797   auto ToD = Import(FromD, Lang_CXX03);
1798 
1799   SourceManager &ToSM = ToAST->getASTContext().getSourceManager();
1800   SourceManager &FromSM = FromD->getASTContext().getSourceManager();
1801   CompareSourceRanges(ToD->getSourceRange(), FromD->getSourceRange(), ToSM,
1802                       FromSM);
1803 }
1804 
1805 TEST_P(
1806     ASTImporterOptionSpecificTestBase,
1807     ImportDefinitionOfClassTemplateSpecIfThereIsAnExistingFwdDeclAndDefinition) {
1808   Decl *ToTU = getToTuDecl(
1809       R"(
1810       template <typename T>
1811       struct B;
1812 
1813       template <>
1814       struct B<int> {};
1815 
1816       template <>
1817       struct B<int>;
1818       )",
1819       Lang_CXX03);
1820   // We should have only one definition.
1821   ASSERT_EQ(1u, DeclCounterWithPredicate<ClassTemplateSpecializationDecl>(
1822                     [](const ClassTemplateSpecializationDecl *T) {
1823                       return T->isThisDeclarationADefinition();
1824                     })
1825                     .match(ToTU, classTemplateSpecializationDecl()));
1826 
1827   Decl *FromTU = getTuDecl(
1828       R"(
1829       template <typename T>
1830       struct B;
1831 
1832       template <>
1833       struct B<int> {};
1834       )",
1835       Lang_CXX03, "input1.cc");
1836   auto *FromD = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
1837       FromTU, classTemplateSpecializationDecl(hasName("B")));
1838 
1839   Import(FromD, Lang_CXX03);
1840 
1841   // We should have only one definition.
1842   EXPECT_EQ(1u, DeclCounterWithPredicate<ClassTemplateSpecializationDecl>(
1843                     [](const ClassTemplateSpecializationDecl *T) {
1844                       return T->isThisDeclarationADefinition();
1845                     })
1846                     .match(ToTU, classTemplateSpecializationDecl()));
1847 }
1848 
1849 TEST_P(ASTImporterOptionSpecificTestBase, ObjectsWithUnnamedStructType) {
1850   Decl *FromTU = getTuDecl(
1851       R"(
1852       struct { int a; int b; } object0 = { 2, 3 };
1853       struct { int x; int y; int z; } object1;
1854       )",
1855       Lang_CXX03, "input0.cc");
1856 
1857   auto *Obj0 =
1858       FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("object0")));
1859   auto *From0 = getRecordDecl(Obj0);
1860   auto *Obj1 =
1861       FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("object1")));
1862   auto *From1 = getRecordDecl(Obj1);
1863 
1864   auto *To0 = Import(From0, Lang_CXX03);
1865   auto *To1 = Import(From1, Lang_CXX03);
1866 
1867   EXPECT_TRUE(To0);
1868   EXPECT_TRUE(To1);
1869   EXPECT_NE(To0, To1);
1870   EXPECT_NE(To0->getCanonicalDecl(), To1->getCanonicalDecl());
1871 }
1872 
1873 TEST_P(ASTImporterOptionSpecificTestBase, AnonymousRecords) {
1874   auto *Code =
1875       R"(
1876       struct X {
1877         struct { int a; };
1878         struct { int b; };
1879       };
1880       )";
1881   Decl *FromTU0 = getTuDecl(Code, Lang_C99, "input0.c");
1882 
1883   Decl *FromTU1 = getTuDecl(Code, Lang_C99, "input1.c");
1884 
1885   auto *X0 =
1886       FirstDeclMatcher<RecordDecl>().match(FromTU0, recordDecl(hasName("X")));
1887   auto *X1 =
1888       FirstDeclMatcher<RecordDecl>().match(FromTU1, recordDecl(hasName("X")));
1889   Import(X0, Lang_C99);
1890   Import(X1, Lang_C99);
1891 
1892   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
1893   // We expect no (ODR) warning during the import.
1894   EXPECT_EQ(0u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
1895   EXPECT_EQ(1u,
1896             DeclCounter<RecordDecl>().match(ToTU, recordDecl(hasName("X"))));
1897 }
1898 
1899 TEST_P(ASTImporterOptionSpecificTestBase, AnonymousRecordsReversed) {
1900   Decl *FromTU0 = getTuDecl(
1901       R"(
1902       struct X {
1903         struct { int a; };
1904         struct { int b; };
1905       };
1906       )",
1907       Lang_C99, "input0.c");
1908 
1909   Decl *FromTU1 = getTuDecl(
1910       R"(
1911       struct X { // reversed order
1912         struct { int b; };
1913         struct { int a; };
1914       };
1915       )",
1916       Lang_C99, "input1.c");
1917 
1918   auto *X0 =
1919       FirstDeclMatcher<RecordDecl>().match(FromTU0, recordDecl(hasName("X")));
1920   auto *X1 =
1921       FirstDeclMatcher<RecordDecl>().match(FromTU1, recordDecl(hasName("X")));
1922   Import(X0, Lang_C99);
1923   Import(X1, Lang_C99);
1924 
1925   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
1926   // We expect one (ODR) warning during the import.
1927   EXPECT_EQ(1u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
1928   EXPECT_EQ(1u,
1929             DeclCounter<RecordDecl>().match(ToTU, recordDecl(hasName("X"))));
1930 }
1931 
1932 TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag) {
1933   auto Pattern = varDecl(hasName("x"));
1934   VarDecl *Imported1;
1935   {
1936     Decl *FromTU = getTuDecl("extern int x;", Lang_CXX03, "input0.cc");
1937     auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
1938     Imported1 = cast<VarDecl>(Import(FromD, Lang_CXX03));
1939   }
1940   VarDecl *Imported2;
1941   {
1942     Decl *FromTU = getTuDecl("int x;", Lang_CXX03, "input1.cc");
1943     auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
1944     Imported2 = cast<VarDecl>(Import(FromD, Lang_CXX03));
1945   }
1946   EXPECT_EQ(Imported1->getCanonicalDecl(), Imported2->getCanonicalDecl());
1947   EXPECT_FALSE(Imported2->isUsed(false));
1948   {
1949     Decl *FromTU = getTuDecl("extern int x; int f() { return x; }", Lang_CXX03,
1950                              "input2.cc");
1951     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
1952         FromTU, functionDecl(hasName("f")));
1953     Import(FromD, Lang_CXX03);
1954   }
1955   EXPECT_TRUE(Imported2->isUsed(false));
1956 }
1957 
1958 TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag2) {
1959   auto Pattern = varDecl(hasName("x"));
1960   VarDecl *ExistingD;
1961   {
1962     Decl *ToTU = getToTuDecl("int x = 1;", Lang_CXX03);
1963     ExistingD = FirstDeclMatcher<VarDecl>().match(ToTU, Pattern);
1964   }
1965   EXPECT_FALSE(ExistingD->isUsed(false));
1966   {
1967     Decl *FromTU =
1968         getTuDecl("int x = 1; int f() { return x; }", Lang_CXX03, "input1.cc");
1969     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
1970         FromTU, functionDecl(hasName("f")));
1971     Import(FromD, Lang_CXX03);
1972   }
1973   EXPECT_TRUE(ExistingD->isUsed(false));
1974 }
1975 
1976 TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag3) {
1977   auto Pattern = varDecl(hasName("a"));
1978   VarDecl *ExistingD;
1979   {
1980     Decl *ToTU = getToTuDecl(
1981         R"(
1982         struct A {
1983           static const int a = 1;
1984         };
1985         )",
1986         Lang_CXX03);
1987     ExistingD = FirstDeclMatcher<VarDecl>().match(ToTU, Pattern);
1988   }
1989   EXPECT_FALSE(ExistingD->isUsed(false));
1990   {
1991     Decl *FromTU = getTuDecl(
1992         R"(
1993         struct A {
1994           static const int a = 1;
1995         };
1996         const int *f() { return &A::a; } // requires storage,
1997                                          // thus used flag will be set
1998         )",
1999         Lang_CXX03, "input1.cc");
2000     auto *FromFunD = FirstDeclMatcher<FunctionDecl>().match(
2001         FromTU, functionDecl(hasName("f")));
2002     auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
2003     ASSERT_TRUE(FromD->isUsed(false));
2004     Import(FromFunD, Lang_CXX03);
2005   }
2006   EXPECT_TRUE(ExistingD->isUsed(false));
2007 }
2008 
2009 TEST_P(ASTImporterOptionSpecificTestBase, ReimportWithUsedFlag) {
2010   auto Pattern = varDecl(hasName("x"));
2011 
2012   Decl *FromTU = getTuDecl("int x;", Lang_CXX03, "input0.cc");
2013   auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
2014 
2015   auto *Imported1 = cast<VarDecl>(Import(FromD, Lang_CXX03));
2016 
2017   ASSERT_FALSE(Imported1->isUsed(false));
2018 
2019   FromD->setIsUsed();
2020   auto *Imported2 = cast<VarDecl>(Import(FromD, Lang_CXX03));
2021 
2022   EXPECT_EQ(Imported1, Imported2);
2023   EXPECT_TRUE(Imported2->isUsed(false));
2024 }
2025 
2026 struct ImportFunctions : ASTImporterOptionSpecificTestBase {};
2027 
2028 TEST_P(ImportFunctions, ImportPrototypeOfRecursiveFunction) {
2029   Decl *FromTU = getTuDecl("void f(); void f() { f(); }", Lang_CXX03);
2030   auto Pattern = functionDecl(hasName("f"));
2031   auto *From =
2032       FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern); // Proto
2033 
2034   Decl *ImportedD = Import(From, Lang_CXX03);
2035   Decl *ToTU = ImportedD->getTranslationUnitDecl();
2036 
2037   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2038   auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2039   auto *To1 = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2040   EXPECT_TRUE(ImportedD == To0);
2041   EXPECT_FALSE(To0->doesThisDeclarationHaveABody());
2042   EXPECT_TRUE(To1->doesThisDeclarationHaveABody());
2043   EXPECT_EQ(To1->getPreviousDecl(), To0);
2044 }
2045 
2046 TEST_P(ImportFunctions, ImportDefinitionOfRecursiveFunction) {
2047   Decl *FromTU = getTuDecl("void f(); void f() { f(); }", Lang_CXX03);
2048   auto Pattern = functionDecl(hasName("f"));
2049   auto *From =
2050       LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern); // Def
2051 
2052   Decl *ImportedD = Import(From, Lang_CXX03);
2053   Decl *ToTU = ImportedD->getTranslationUnitDecl();
2054 
2055   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2056   auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2057   auto *To1 = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2058   EXPECT_TRUE(ImportedD == To1);
2059   EXPECT_FALSE(To0->doesThisDeclarationHaveABody());
2060   EXPECT_TRUE(To1->doesThisDeclarationHaveABody());
2061   EXPECT_EQ(To1->getPreviousDecl(), To0);
2062 }
2063 
2064 TEST_P(ImportFunctions, OverriddenMethodsShouldBeImported) {
2065   auto Code =
2066       R"(
2067       struct B { virtual void f(); };
2068       void B::f() {}
2069       struct D : B { void f(); };
2070       )";
2071   auto Pattern =
2072       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
2073   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
2074   CXXMethodDecl *Proto =
2075       FirstDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);
2076 
2077   ASSERT_EQ(Proto->size_overridden_methods(), 1u);
2078   CXXMethodDecl *To = cast<CXXMethodDecl>(Import(Proto, Lang_CXX03));
2079   EXPECT_EQ(To->size_overridden_methods(), 1u);
2080 }
2081 
2082 TEST_P(ImportFunctions, VirtualFlagShouldBePreservedWhenImportingPrototype) {
2083   auto Code =
2084       R"(
2085       struct B { virtual void f(); };
2086       void B::f() {}
2087       )";
2088   auto Pattern =
2089       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
2090   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
2091   CXXMethodDecl *Proto =
2092       FirstDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);
2093   CXXMethodDecl *Def = LastDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);
2094 
2095   ASSERT_TRUE(Proto->isVirtual());
2096   ASSERT_TRUE(Def->isVirtual());
2097   CXXMethodDecl *To = cast<CXXMethodDecl>(Import(Proto, Lang_CXX03));
2098   EXPECT_TRUE(To->isVirtual());
2099 }
2100 
2101 TEST_P(ImportFunctions,
2102        ImportDefinitionIfThereIsAnExistingDefinitionAndFwdDecl) {
2103   Decl *ToTU = getToTuDecl(
2104       R"(
2105       void f() {}
2106       void f();
2107       )",
2108       Lang_CXX03);
2109   ASSERT_EQ(1u,
2110             DeclCounterWithPredicate<FunctionDecl>([](const FunctionDecl *FD) {
2111               return FD->doesThisDeclarationHaveABody();
2112             }).match(ToTU, functionDecl()));
2113 
2114   Decl *FromTU = getTuDecl("void f() {}", Lang_CXX03, "input0.cc");
2115   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
2116 
2117   Import(FromD, Lang_CXX03);
2118 
2119   EXPECT_EQ(1u,
2120             DeclCounterWithPredicate<FunctionDecl>([](const FunctionDecl *FD) {
2121               return FD->doesThisDeclarationHaveABody();
2122             }).match(ToTU, functionDecl()));
2123 }
2124 
2125 TEST_P(ImportFunctions, ImportOverriddenMethodTwice) {
2126   auto Code =
2127       R"(
2128       struct B { virtual void f(); };
2129       struct D:B { void f(); };
2130       )";
2131   auto BFP =
2132       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
2133   auto DFP =
2134       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
2135 
2136   Decl *FromTU0 = getTuDecl(Code, Lang_CXX03);
2137   auto *DF = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
2138   Import(DF, Lang_CXX03);
2139 
2140   Decl *FromTU1 = getTuDecl(Code, Lang_CXX03, "input1.cc");
2141   auto *BF = FirstDeclMatcher<CXXMethodDecl>().match(FromTU1, BFP);
2142   Import(BF, Lang_CXX03);
2143 
2144   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2145 
2146   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
2147   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
2148 }
2149 
2150 TEST_P(ImportFunctions, ImportOverriddenMethodTwiceDefinitionFirst) {
2151   auto CodeWithoutDef =
2152       R"(
2153       struct B { virtual void f(); };
2154       struct D:B { void f(); };
2155       )";
2156   auto CodeWithDef =
2157       R"(
2158     struct B { virtual void f(){}; };
2159     struct D:B { void f(){}; };
2160   )";
2161   auto BFP =
2162       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
2163   auto DFP =
2164       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
2165   auto BFDefP = cxxMethodDecl(
2166       hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
2167   auto DFDefP = cxxMethodDecl(
2168       hasName("f"), hasParent(cxxRecordDecl(hasName("D"))), isDefinition());
2169   auto FDefAllP = cxxMethodDecl(hasName("f"), isDefinition());
2170 
2171   {
2172     Decl *FromTU = getTuDecl(CodeWithDef, Lang_CXX03, "input0.cc");
2173     auto *FromD = FirstDeclMatcher<CXXMethodDecl>().match(FromTU, DFP);
2174     Import(FromD, Lang_CXX03);
2175   }
2176   {
2177     Decl *FromTU = getTuDecl(CodeWithoutDef, Lang_CXX03, "input1.cc");
2178     auto *FromB = FirstDeclMatcher<CXXMethodDecl>().match(FromTU, BFP);
2179     Import(FromB, Lang_CXX03);
2180   }
2181 
2182   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2183 
2184   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
2185   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
2186   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 1u);
2187   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFDefP), 1u);
2188   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FDefAllP), 2u);
2189 }
2190 
2191 TEST_P(ImportFunctions, ImportOverriddenMethodTwiceOutOfClassDef) {
2192   auto Code =
2193       R"(
2194       struct B { virtual void f(); };
2195       struct D:B { void f(); };
2196       void B::f(){};
2197       )";
2198 
2199   auto BFP =
2200       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
2201   auto BFDefP = cxxMethodDecl(
2202       hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
2203   auto DFP = cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))),
2204                            unless(isDefinition()));
2205 
2206   Decl *FromTU0 = getTuDecl(Code, Lang_CXX03);
2207   auto *D = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
2208   Import(D, Lang_CXX03);
2209 
2210   Decl *FromTU1 = getTuDecl(Code, Lang_CXX03, "input1.cc");
2211   auto *B = FirstDeclMatcher<CXXMethodDecl>().match(FromTU1, BFP);
2212   Import(B, Lang_CXX03);
2213 
2214   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2215 
2216   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
2217   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 0u);
2218 
2219   auto *ToB = FirstDeclMatcher<CXXRecordDecl>().match(
2220       ToTU, cxxRecordDecl(hasName("B")));
2221   auto *ToBFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, BFP);
2222   auto *ToBFOutOfClass = FirstDeclMatcher<CXXMethodDecl>().match(
2223       ToTU, cxxMethodDecl(hasName("f"), isDefinition()));
2224 
2225   // The definition should be out-of-class.
2226   EXPECT_NE(ToBFInClass, ToBFOutOfClass);
2227   EXPECT_NE(ToBFInClass->getLexicalDeclContext(),
2228             ToBFOutOfClass->getLexicalDeclContext());
2229   EXPECT_EQ(ToBFOutOfClass->getDeclContext(), ToB);
2230   EXPECT_EQ(ToBFOutOfClass->getLexicalDeclContext(), ToTU);
2231 
2232   // Check that the redecl chain is intact.
2233   EXPECT_EQ(ToBFOutOfClass->getPreviousDecl(), ToBFInClass);
2234 }
2235 
2236 TEST_P(ImportFunctions,
2237        ImportOverriddenMethodTwiceOutOfClassDefInSeparateCode) {
2238   auto CodeTU0 =
2239       R"(
2240       struct B { virtual void f(); };
2241       struct D:B { void f(); };
2242       )";
2243   auto CodeTU1 =
2244       R"(
2245       struct B { virtual void f(); };
2246       struct D:B { void f(); };
2247       void B::f(){}
2248       void D::f(){}
2249       void foo(B &b, D &d) { b.f(); d.f(); }
2250       )";
2251 
2252   auto BFP =
2253       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
2254   auto BFDefP = cxxMethodDecl(
2255       hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
2256   auto DFP =
2257       cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
2258   auto DFDefP = cxxMethodDecl(
2259       hasName("f"), hasParent(cxxRecordDecl(hasName("D"))), isDefinition());
2260   auto FooDef = functionDecl(hasName("foo"));
2261 
2262   {
2263     Decl *FromTU0 = getTuDecl(CodeTU0, Lang_CXX03, "input0.cc");
2264     auto *D = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
2265     Import(D, Lang_CXX03);
2266   }
2267 
2268   {
2269     Decl *FromTU1 = getTuDecl(CodeTU1, Lang_CXX03, "input1.cc");
2270     auto *Foo = FirstDeclMatcher<FunctionDecl>().match(FromTU1, FooDef);
2271     Import(Foo, Lang_CXX03);
2272   }
2273 
2274   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2275 
2276   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
2277   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
2278   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 0u);
2279   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFDefP), 0u);
2280 
2281   auto *ToB = FirstDeclMatcher<CXXRecordDecl>().match(
2282       ToTU, cxxRecordDecl(hasName("B")));
2283   auto *ToD = FirstDeclMatcher<CXXRecordDecl>().match(
2284       ToTU, cxxRecordDecl(hasName("D")));
2285   auto *ToBFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, BFP);
2286   auto *ToBFOutOfClass = FirstDeclMatcher<CXXMethodDecl>().match(
2287       ToTU, cxxMethodDecl(hasName("f"), isDefinition()));
2288   auto *ToDFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, DFP);
2289   auto *ToDFOutOfClass = LastDeclMatcher<CXXMethodDecl>().match(
2290       ToTU, cxxMethodDecl(hasName("f"), isDefinition()));
2291 
2292   // The definition should be out-of-class.
2293   EXPECT_NE(ToBFInClass, ToBFOutOfClass);
2294   EXPECT_NE(ToBFInClass->getLexicalDeclContext(),
2295             ToBFOutOfClass->getLexicalDeclContext());
2296   EXPECT_EQ(ToBFOutOfClass->getDeclContext(), ToB);
2297   EXPECT_EQ(ToBFOutOfClass->getLexicalDeclContext(), ToTU);
2298 
2299   EXPECT_NE(ToDFInClass, ToDFOutOfClass);
2300   EXPECT_NE(ToDFInClass->getLexicalDeclContext(),
2301             ToDFOutOfClass->getLexicalDeclContext());
2302   EXPECT_EQ(ToDFOutOfClass->getDeclContext(), ToD);
2303   EXPECT_EQ(ToDFOutOfClass->getLexicalDeclContext(), ToTU);
2304 
2305   // Check that the redecl chain is intact.
2306   EXPECT_EQ(ToBFOutOfClass->getPreviousDecl(), ToBFInClass);
2307   EXPECT_EQ(ToDFOutOfClass->getPreviousDecl(), ToDFInClass);
2308 }
2309 
2310 TEST_P(ASTImporterOptionSpecificTestBase, ImportVariableChainInC) {
2311     std::string Code = "static int v; static int v = 0;";
2312     auto Pattern = varDecl(hasName("v"));
2313 
2314     TranslationUnitDecl *FromTu = getTuDecl(Code, Lang_C99, "input0.c");
2315 
2316     auto *From0 = FirstDeclMatcher<VarDecl>().match(FromTu, Pattern);
2317     auto *From1 = LastDeclMatcher<VarDecl>().match(FromTu, Pattern);
2318 
2319     auto *To0 = Import(From0, Lang_C99);
2320     auto *To1 = Import(From1, Lang_C99);
2321 
2322     EXPECT_TRUE(To0);
2323     ASSERT_TRUE(To1);
2324     EXPECT_NE(To0, To1);
2325     EXPECT_EQ(To1->getPreviousDecl(), To0);
2326 }
2327 
2328 TEST_P(ImportFunctions, ImportFromDifferentScopedAnonNamespace) {
2329   TranslationUnitDecl *FromTu =
2330       getTuDecl("namespace NS0 { namespace { void f(); } }"
2331                 "namespace NS1 { namespace { void f(); } }",
2332                 Lang_CXX03, "input0.cc");
2333   auto Pattern = functionDecl(hasName("f"));
2334 
2335   auto *FromF0 = FirstDeclMatcher<FunctionDecl>().match(FromTu, Pattern);
2336   auto *FromF1 = LastDeclMatcher<FunctionDecl>().match(FromTu, Pattern);
2337 
2338   auto *ToF0 = Import(FromF0, Lang_CXX03);
2339   auto *ToF1 = Import(FromF1, Lang_CXX03);
2340 
2341   EXPECT_TRUE(ToF0);
2342   ASSERT_TRUE(ToF1);
2343   EXPECT_NE(ToF0, ToF1);
2344   EXPECT_FALSE(ToF1->getPreviousDecl());
2345 }
2346 
2347 TEST_P(ImportFunctions, ImportFunctionFromUnnamedNamespace) {
2348   {
2349     Decl *FromTU = getTuDecl("namespace { void f() {} } void g0() { f(); }",
2350                              Lang_CXX03, "input0.cc");
2351     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2352         FromTU, functionDecl(hasName("g0")));
2353 
2354     Import(FromD, Lang_CXX03);
2355   }
2356   {
2357     Decl *FromTU =
2358         getTuDecl("namespace { void f() { int a; } } void g1() { f(); }",
2359                   Lang_CXX03, "input1.cc");
2360     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2361         FromTU, functionDecl(hasName("g1")));
2362     Import(FromD, Lang_CXX03);
2363   }
2364 
2365   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2366   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, functionDecl(hasName("f"))),
2367             2u);
2368 }
2369 
2370 TEST_P(ImportFunctions, ImportImplicitFunctionsInLambda) {
2371   Decl *FromTU = getTuDecl(
2372       R"(
2373       void foo() {
2374         (void)[]() { ; };
2375       }
2376       )",
2377       Lang_CXX11);
2378   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2379       FromTU, functionDecl(hasName("foo")));
2380   auto *ToD = Import(FromD, Lang_CXX03);
2381   EXPECT_TRUE(ToD);
2382   CXXRecordDecl *LambdaRec =
2383       cast<LambdaExpr>(cast<CStyleCastExpr>(
2384                            *cast<CompoundStmt>(ToD->getBody())->body_begin())
2385                            ->getSubExpr())
2386           ->getLambdaClass();
2387   EXPECT_TRUE(LambdaRec->getDestructor());
2388 }
2389 
2390 TEST_P(ImportFunctions,
2391        CallExprOfMemberFunctionTemplateWithExplicitTemplateArgs) {
2392   Decl *FromTU = getTuDecl(
2393       R"(
2394       struct X {
2395         template <typename T>
2396         void foo(){}
2397       };
2398       void f() {
2399         X x;
2400         x.foo<int>();
2401       }
2402       )",
2403       Lang_CXX03);
2404   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2405       FromTU, functionDecl(hasName("f")));
2406   auto *ToD = Import(FromD, Lang_CXX03);
2407   EXPECT_TRUE(ToD);
2408   EXPECT_TRUE(MatchVerifier<FunctionDecl>().match(
2409       ToD, functionDecl(hasName("f"), hasDescendant(declRefExpr()))));
2410 }
2411 
2412 TEST_P(ImportFunctions,
2413        DependentCallExprOfMemberFunctionTemplateWithExplicitTemplateArgs) {
2414   Decl *FromTU = getTuDecl(
2415       R"(
2416       struct X {
2417         template <typename T>
2418         void foo(){}
2419       };
2420       template <typename T>
2421       void f() {
2422         X x;
2423         x.foo<T>();
2424       }
2425       void g() {
2426         f<int>();
2427       }
2428       )",
2429       Lang_CXX03);
2430   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2431       FromTU, functionDecl(hasName("g")));
2432   auto *ToD = Import(FromD, Lang_CXX03);
2433   EXPECT_TRUE(ToD);
2434   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2435   EXPECT_TRUE(MatchVerifier<TranslationUnitDecl>().match(
2436       ToTU, translationUnitDecl(hasDescendant(
2437                 functionDecl(hasName("f"), hasDescendant(declRefExpr()))))));
2438 }
2439 
2440 struct ImportFunctionTemplates : ASTImporterOptionSpecificTestBase {};
2441 
2442 TEST_P(ImportFunctionTemplates, ImportFunctionTemplateInRecordDeclTwice) {
2443   auto Code =
2444       R"(
2445       class X {
2446         template <class T>
2447         void f(T t);
2448       };
2449       )";
2450   Decl *FromTU1 = getTuDecl(Code, Lang_CXX03, "input1.cc");
2451   auto *FromD1 = FirstDeclMatcher<FunctionTemplateDecl>().match(
2452       FromTU1, functionTemplateDecl(hasName("f")));
2453   auto *ToD1 = Import(FromD1, Lang_CXX03);
2454   Decl *FromTU2 = getTuDecl(Code, Lang_CXX03, "input2.cc");
2455   auto *FromD2 = FirstDeclMatcher<FunctionTemplateDecl>().match(
2456       FromTU2, functionTemplateDecl(hasName("f")));
2457   auto *ToD2 = Import(FromD2, Lang_CXX03);
2458   EXPECT_EQ(ToD1, ToD2);
2459 }
2460 
2461 TEST_P(ImportFunctionTemplates,
2462        ImportFunctionTemplateWithDefInRecordDeclTwice) {
2463   auto Code =
2464       R"(
2465       class X {
2466         template <class T>
2467         void f(T t);
2468       };
2469       template <class T>
2470       void X::f(T t) {};
2471       )";
2472   Decl *FromTU1 = getTuDecl(Code, Lang_CXX03, "input1.cc");
2473   auto *FromD1 = FirstDeclMatcher<FunctionTemplateDecl>().match(
2474       FromTU1, functionTemplateDecl(hasName("f")));
2475   auto *ToD1 = Import(FromD1, Lang_CXX03);
2476   Decl *FromTU2 = getTuDecl(Code, Lang_CXX03, "input2.cc");
2477   auto *FromD2 = FirstDeclMatcher<FunctionTemplateDecl>().match(
2478       FromTU2, functionTemplateDecl(hasName("f")));
2479   auto *ToD2 = Import(FromD2, Lang_CXX03);
2480   EXPECT_EQ(ToD1, ToD2);
2481 }
2482 
2483 TEST_P(ImportFunctionTemplates,
2484        ImportFunctionWhenThereIsAFunTemplateWithSameName) {
2485   getToTuDecl(
2486       R"(
2487       template <typename T>
2488       void foo(T) {}
2489       void foo();
2490       )",
2491       Lang_CXX03);
2492   Decl *FromTU = getTuDecl("void foo();", Lang_CXX03);
2493   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
2494       FromTU, functionDecl(hasName("foo")));
2495   auto *ImportedD = Import(FromD, Lang_CXX03);
2496   EXPECT_TRUE(ImportedD);
2497 }
2498 
2499 TEST_P(ImportFunctionTemplates,
2500        ImportConstructorWhenThereIsAFunTemplateWithSameName) {
2501   auto Code =
2502       R"(
2503       struct Foo {
2504         template <typename T>
2505         Foo(T) {}
2506         Foo();
2507       };
2508       )";
2509   getToTuDecl(Code, Lang_CXX03);
2510   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
2511   auto *FromD =
2512       LastDeclMatcher<CXXConstructorDecl>().match(FromTU, cxxConstructorDecl());
2513   auto *ImportedD = Import(FromD, Lang_CXX03);
2514   EXPECT_TRUE(ImportedD);
2515 }
2516 
2517 TEST_P(ImportFunctionTemplates,
2518        ImportOperatorWhenThereIsAFunTemplateWithSameName) {
2519   getToTuDecl(
2520       R"(
2521       template <typename T>
2522       void operator<(T,T) {}
2523       struct X{};
2524       void operator<(X, X);
2525       )",
2526       Lang_CXX03);
2527   Decl *FromTU = getTuDecl(
2528       R"(
2529       struct X{};
2530       void operator<(X, X);
2531       )",
2532       Lang_CXX03);
2533   auto *FromD = LastDeclMatcher<FunctionDecl>().match(
2534       FromTU, functionDecl(hasOverloadedOperatorName("<")));
2535   auto *ImportedD = Import(FromD, Lang_CXX03);
2536   EXPECT_TRUE(ImportedD);
2537 }
2538 
2539 struct ImportFriendFunctions : ImportFunctions {};
2540 
2541 TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainProto) {
2542   auto Pattern = functionDecl(hasName("f"));
2543 
2544   Decl *FromTU = getTuDecl("struct X { friend void f(); };"
2545                            "void f();",
2546                            Lang_CXX03, "input0.cc");
2547   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2548 
2549   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2550   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2551   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2552   EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
2553   auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2554   EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
2555   EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
2556 }
2557 
2558 TEST_P(ImportFriendFunctions,
2559        ImportFriendFunctionRedeclChainProto_OutOfClassProtoFirst) {
2560   auto Pattern = functionDecl(hasName("f"));
2561 
2562   Decl *FromTU = getTuDecl("void f();"
2563                            "struct X { friend void f(); };",
2564                            Lang_CXX03, "input0.cc");
2565   auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2566 
2567   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2568   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2569   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2570   EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
2571   auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2572   EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
2573   EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
2574 }
2575 
2576 TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainDef) {
2577   auto Pattern = functionDecl(hasName("f"));
2578 
2579   Decl *FromTU = getTuDecl("struct X { friend void f(){} };"
2580                            "void f();",
2581                            Lang_CXX03, "input0.cc");
2582   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2583 
2584   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2585   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2586   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2587   EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
2588   auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2589   EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
2590   EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
2591 }
2592 
2593 TEST_P(ImportFriendFunctions,
2594        ImportFriendFunctionRedeclChainDef_OutOfClassDef) {
2595   auto Pattern = functionDecl(hasName("f"));
2596 
2597   Decl *FromTU = getTuDecl("struct X { friend void f(); };"
2598                            "void f(){}",
2599                            Lang_CXX03, "input0.cc");
2600   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2601 
2602   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2603   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2604   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2605   EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
2606   auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
2607   EXPECT_TRUE(ToFD->doesThisDeclarationHaveABody());
2608   EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
2609 }
2610 
2611 TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainDefWithClass) {
2612   auto Pattern = functionDecl(hasName("f"));
2613 
2614   Decl *FromTU = getTuDecl(
2615       R"(
2616         class X;
2617         void f(X *x){}
2618         class X{
2619         friend void f(X *x);
2620         };
2621       )",
2622       Lang_CXX03, "input0.cc");
2623   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2624 
2625   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2626   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2627   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2628   EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
2629   auto *InClassFD = cast<FunctionDecl>(FirstDeclMatcher<FriendDecl>()
2630                                               .match(ToTU, friendDecl())
2631                                               ->getFriendDecl());
2632   EXPECT_FALSE(InClassFD->doesThisDeclarationHaveABody());
2633   EXPECT_EQ(InClassFD->getPreviousDecl(), ImportedD);
2634   // The parameters must refer the same type
2635   EXPECT_EQ((*InClassFD->param_begin())->getOriginalType(),
2636             (*ImportedD->param_begin())->getOriginalType());
2637 }
2638 
2639 TEST_P(ImportFriendFunctions,
2640        ImportFriendFunctionRedeclChainDefWithClass_ImportTheProto) {
2641   auto Pattern = functionDecl(hasName("f"));
2642 
2643   Decl *FromTU = getTuDecl(
2644       R"(
2645         class X;
2646         void f(X *x){}
2647         class X{
2648         friend void f(X *x);
2649         };
2650       )",
2651       Lang_CXX03, "input0.cc");
2652   auto *FromD = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2653 
2654   auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2655   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2656   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2657   EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
2658   auto *OutOfClassFD = FirstDeclMatcher<FunctionDecl>().match(
2659       ToTU, functionDecl(unless(hasParent(friendDecl()))));
2660 
2661   EXPECT_TRUE(OutOfClassFD->doesThisDeclarationHaveABody());
2662   EXPECT_EQ(ImportedD->getPreviousDecl(), OutOfClassFD);
2663   // The parameters must refer the same type
2664   EXPECT_EQ((*OutOfClassFD->param_begin())->getOriginalType(),
2665             (*ImportedD->param_begin())->getOriginalType());
2666 }
2667 
2668 TEST_P(ImportFriendFunctions, ImportFriendFunctionFromMultipleTU) {
2669   auto Pattern = functionDecl(hasName("f"));
2670 
2671   FunctionDecl *ImportedD;
2672   {
2673     Decl *FromTU =
2674         getTuDecl("struct X { friend void f(){} };", Lang_CXX03, "input0.cc");
2675     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2676     ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2677   }
2678   FunctionDecl *ImportedD1;
2679   {
2680     Decl *FromTU = getTuDecl("void f();", Lang_CXX03, "input1.cc");
2681     auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
2682     ImportedD1 = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2683   }
2684 
2685   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2686   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2687   EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
2688   EXPECT_FALSE(ImportedD1->doesThisDeclarationHaveABody());
2689   EXPECT_EQ(ImportedD1->getPreviousDecl(), ImportedD);
2690 }
2691 
2692 TEST_P(ImportFriendFunctions, Lookup) {
2693   auto FunctionPattern = functionDecl(hasName("f"));
2694   auto ClassPattern = cxxRecordDecl(hasName("X"));
2695 
2696   TranslationUnitDecl *FromTU =
2697       getTuDecl("struct X { friend void f(); };", Lang_CXX03, "input0.cc");
2698   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
2699   ASSERT_TRUE(FromD->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2700   ASSERT_FALSE(FromD->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2701   {
2702     auto FromName = FromD->getDeclName();
2703     auto *Class = FirstDeclMatcher<CXXRecordDecl>().match(FromTU, ClassPattern);
2704     auto LookupRes = Class->noload_lookup(FromName);
2705     ASSERT_TRUE(LookupRes.empty());
2706     LookupRes = FromTU->noload_lookup(FromName);
2707     ASSERT_TRUE(LookupRes.isSingleResult());
2708   }
2709 
2710   auto *ToD = cast<FunctionDecl>(Import(FromD, Lang_CXX03));
2711   auto ToName = ToD->getDeclName();
2712 
2713   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2714   auto *Class = FirstDeclMatcher<CXXRecordDecl>().match(ToTU, ClassPattern);
2715   auto LookupRes = Class->noload_lookup(ToName);
2716   EXPECT_TRUE(LookupRes.empty());
2717   LookupRes = ToTU->noload_lookup(ToName);
2718   EXPECT_TRUE(LookupRes.isSingleResult());
2719 
2720   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FunctionPattern), 1u);
2721   auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
2722   EXPECT_TRUE(To0->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2723   EXPECT_FALSE(To0->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2724 }
2725 
2726 TEST_P(ImportFriendFunctions, LookupWithProtoAfter) {
2727   auto FunctionPattern = functionDecl(hasName("f"));
2728   auto ClassPattern = cxxRecordDecl(hasName("X"));
2729 
2730   TranslationUnitDecl *FromTU =
2731       getTuDecl("struct X { friend void f(); };"
2732                 // This proto decl makes f available to normal
2733                 // lookup, otherwise it is hidden.
2734                 // Normal C++ lookup (implemented in
2735                 // `clang::Sema::CppLookupName()` and in `LookupDirect()`)
2736                 // returns the found `NamedDecl` only if the set IDNS is matched
2737                 "void f();",
2738                 Lang_CXX03, "input0.cc");
2739   auto *FromFriend =
2740       FirstDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
2741   auto *FromNormal =
2742       LastDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
2743   ASSERT_TRUE(FromFriend->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2744   ASSERT_FALSE(FromFriend->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2745   ASSERT_FALSE(FromNormal->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2746   ASSERT_TRUE(FromNormal->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2747 
2748   auto FromName = FromFriend->getDeclName();
2749   auto *FromClass =
2750       FirstDeclMatcher<CXXRecordDecl>().match(FromTU, ClassPattern);
2751   auto LookupRes = FromClass->noload_lookup(FromName);
2752   ASSERT_TRUE(LookupRes.empty());
2753   LookupRes = FromTU->noload_lookup(FromName);
2754   ASSERT_TRUE(LookupRes.isSingleResult());
2755 
2756   auto *ToFriend = cast<FunctionDecl>(Import(FromFriend, Lang_CXX03));
2757   auto ToName = ToFriend->getDeclName();
2758 
2759   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2760   auto *ToClass = FirstDeclMatcher<CXXRecordDecl>().match(ToTU, ClassPattern);
2761   LookupRes = ToClass->noload_lookup(ToName);
2762   EXPECT_TRUE(LookupRes.empty());
2763   LookupRes = ToTU->noload_lookup(ToName);
2764   // Test is disabled because this result is 2.
2765   EXPECT_TRUE(LookupRes.isSingleResult());
2766 
2767   ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FunctionPattern), 2u);
2768   ToFriend = FirstDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
2769   auto *ToNormal = LastDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
2770   EXPECT_TRUE(ToFriend->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2771   EXPECT_FALSE(ToFriend->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2772   EXPECT_FALSE(ToNormal->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2773   EXPECT_TRUE(ToNormal->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2774 }
2775 
2776 TEST_P(ImportFriendFunctions, LookupWithProtoBefore) {
2777   auto FunctionPattern = functionDecl(hasName("f"));
2778   auto ClassPattern = cxxRecordDecl(hasName("X"));
2779 
2780   TranslationUnitDecl *FromTU = getTuDecl("void f();"
2781                                           "struct X { friend void f(); };",
2782                                           Lang_CXX03, "input0.cc");
2783   auto *FromNormal =
2784       FirstDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
2785   auto *FromFriend =
2786       LastDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
2787   ASSERT_FALSE(FromNormal->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2788   ASSERT_TRUE(FromNormal->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2789   ASSERT_TRUE(FromFriend->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2790   ASSERT_TRUE(FromFriend->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2791 
2792   auto FromName = FromNormal->getDeclName();
2793   auto *FromClass =
2794       FirstDeclMatcher<CXXRecordDecl>().match(FromTU, ClassPattern);
2795   auto LookupRes = FromClass->noload_lookup(FromName);
2796   ASSERT_TRUE(LookupRes.empty());
2797   LookupRes = FromTU->noload_lookup(FromName);
2798   ASSERT_TRUE(LookupRes.isSingleResult());
2799 
2800   auto *ToNormal = cast<FunctionDecl>(Import(FromNormal, Lang_CXX03));
2801   auto ToName = ToNormal->getDeclName();
2802   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2803 
2804   auto *ToClass = FirstDeclMatcher<CXXRecordDecl>().match(ToTU, ClassPattern);
2805   LookupRes = ToClass->noload_lookup(ToName);
2806   EXPECT_TRUE(LookupRes.empty());
2807   LookupRes = ToTU->noload_lookup(ToName);
2808   EXPECT_TRUE(LookupRes.isSingleResult());
2809 
2810   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FunctionPattern), 2u);
2811   ToNormal = FirstDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
2812   auto *ToFriend = LastDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
2813   EXPECT_FALSE(ToNormal->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2814   EXPECT_TRUE(ToNormal->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2815   EXPECT_TRUE(ToFriend->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2816   EXPECT_TRUE(ToFriend->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2817 }
2818 
2819 TEST_P(ImportFriendFunctions, ImportFriendChangesLookup) {
2820   auto Pattern = functionDecl(hasName("f"));
2821 
2822   TranslationUnitDecl *FromNormalTU =
2823       getTuDecl("void f();", Lang_CXX03, "input0.cc");
2824   auto *FromNormalF =
2825       FirstDeclMatcher<FunctionDecl>().match(FromNormalTU, Pattern);
2826   TranslationUnitDecl *FromFriendTU =
2827       getTuDecl("class X { friend void f(); };", Lang_CXX03, "input1.cc");
2828   auto *FromFriendF =
2829       FirstDeclMatcher<FunctionDecl>().match(FromFriendTU, Pattern);
2830   auto FromNormalName = FromNormalF->getDeclName();
2831   auto FromFriendName = FromFriendF->getDeclName();
2832 
2833   ASSERT_TRUE(FromNormalF->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2834   ASSERT_FALSE(FromNormalF->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2835   ASSERT_FALSE(FromFriendF->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2836   ASSERT_TRUE(FromFriendF->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2837   auto LookupRes = FromNormalTU->noload_lookup(FromNormalName);
2838   ASSERT_TRUE(LookupRes.isSingleResult());
2839   LookupRes = FromFriendTU->noload_lookup(FromFriendName);
2840   ASSERT_TRUE(LookupRes.isSingleResult());
2841 
2842   auto *ToNormalF = cast<FunctionDecl>(Import(FromNormalF, Lang_CXX03));
2843   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2844   auto ToName = ToNormalF->getDeclName();
2845   EXPECT_TRUE(ToNormalF->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2846   EXPECT_FALSE(ToNormalF->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2847   LookupRes = ToTU->noload_lookup(ToName);
2848   EXPECT_TRUE(LookupRes.isSingleResult());
2849   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 1u);
2850 
2851   auto *ToFriendF = cast<FunctionDecl>(Import(FromFriendF, Lang_CXX03));
2852   LookupRes = ToTU->noload_lookup(ToName);
2853   EXPECT_TRUE(LookupRes.isSingleResult());
2854   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
2855 
2856   EXPECT_TRUE(ToNormalF->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2857   EXPECT_FALSE(ToNormalF->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2858 
2859   EXPECT_TRUE(ToFriendF->isInIdentifierNamespace(Decl::IDNS_Ordinary));
2860   EXPECT_TRUE(ToFriendF->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
2861 }
2862 
2863 TEST_P(ImportFriendFunctions, ImportFriendList) {
2864   TranslationUnitDecl *FromTU = getTuDecl("struct X { friend void f(); };"
2865                                           "void f();",
2866                                           Lang_CXX03, "input0.cc");
2867   auto *FromFriendF = FirstDeclMatcher<FunctionDecl>().match(
2868       FromTU, functionDecl(hasName("f")));
2869 
2870   auto *FromClass = FirstDeclMatcher<CXXRecordDecl>().match(
2871       FromTU, cxxRecordDecl(hasName("X")));
2872   auto *FromFriend = FirstDeclMatcher<FriendDecl>().match(FromTU, friendDecl());
2873   auto FromFriends = FromClass->friends();
2874   unsigned int FrN = 0;
2875   for (auto Fr : FromFriends) {
2876     ASSERT_EQ(Fr, FromFriend);
2877     ++FrN;
2878   }
2879   ASSERT_EQ(FrN, 1u);
2880 
2881   Import(FromFriendF, Lang_CXX03);
2882   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
2883   auto *ToClass = FirstDeclMatcher<CXXRecordDecl>().match(
2884       ToTU, cxxRecordDecl(hasName("X")));
2885   auto *ToFriend = FirstDeclMatcher<FriendDecl>().match(ToTU, friendDecl());
2886   auto ToFriends = ToClass->friends();
2887   FrN = 0;
2888   for (auto Fr : ToFriends) {
2889     EXPECT_EQ(Fr, ToFriend);
2890     ++FrN;
2891   }
2892   EXPECT_EQ(FrN, 1u);
2893 }
2894 
2895 AST_MATCHER_P(TagDecl, hasTypedefForAnonDecl, Matcher<TypedefNameDecl>,
2896               InnerMatcher) {
2897   if (auto *Typedef = Node.getTypedefNameForAnonDecl())
2898     return InnerMatcher.matches(*Typedef, Finder, Builder);
2899   return false;
2900 }
2901 
2902 TEST_P(ImportDecl, ImportEnumSequential) {
2903   CodeFiles Samples{{"main.c",
2904                      {"void foo();"
2905                       "void moo();"
2906                       "int main() { foo(); moo(); }",
2907                       Lang_C99}},
2908 
2909                     {"foo.c",
2910                      {"typedef enum { THING_VALUE } thing_t;"
2911                       "void conflict(thing_t type);"
2912                       "void foo() { (void)THING_VALUE; }"
2913                       "void conflict(thing_t type) {}",
2914                       Lang_C99}},
2915 
2916                     {"moo.c",
2917                      {"typedef enum { THING_VALUE } thing_t;"
2918                       "void conflict(thing_t type);"
2919                       "void moo() { conflict(THING_VALUE); }",
2920                       Lang_C99}}};
2921 
2922   auto VerificationMatcher =
2923       enumDecl(has(enumConstantDecl(hasName("THING_VALUE"))),
2924                hasTypedefForAnonDecl(hasName("thing_t")));
2925 
2926   ImportAction ImportFoo{"foo.c", "main.c", functionDecl(hasName("foo"))},
2927       ImportMoo{"moo.c", "main.c", functionDecl(hasName("moo"))};
2928 
2929   testImportSequence(
2930       Samples, {ImportFoo, ImportMoo}, // "foo", them "moo".
2931       // Just check that there is only one enum decl in the result AST.
2932       "main.c", enumDecl(), VerificationMatcher);
2933 
2934   // For different import order, result should be the same.
2935   testImportSequence(
2936       Samples, {ImportMoo, ImportFoo}, // "moo", them "foo".
2937       // Check that there is only one enum decl in the result AST.
2938       "main.c", enumDecl(), VerificationMatcher);
2939 }
2940 
2941 TEST_P(ImportDecl, ImportFieldOrder) {
2942   MatchVerifier<Decl> Verifier;
2943   testImport("struct declToImport {"
2944              "  int b = a + 2;"
2945              "  int a = 5;"
2946              "};",
2947              Lang_CXX11, "", Lang_CXX11, Verifier,
2948              recordDecl(hasFieldOrder({"b", "a"})));
2949 }
2950 
2951 const internal::VariadicDynCastAllOfMatcher<Expr, DependentScopeDeclRefExpr>
2952     dependentScopeDeclRefExpr;
2953 
2954 TEST_P(ImportExpr, DependentScopeDeclRefExpr) {
2955   MatchVerifier<Decl> Verifier;
2956   testImport("template <typename T> struct S { static T foo; };"
2957              "template <typename T> void declToImport() {"
2958              "  (void) S<T>::foo;"
2959              "}"
2960              "void instantiate() { declToImport<int>(); }"
2961              "template <typename T> T S<T>::foo;",
2962              Lang_CXX11, "", Lang_CXX11, Verifier,
2963              functionTemplateDecl(has(functionDecl(has(compoundStmt(
2964                  has(cStyleCastExpr(has(dependentScopeDeclRefExpr())))))))));
2965 
2966   testImport("template <typename T> struct S {"
2967              "template<typename S> static void foo(){};"
2968              "};"
2969              "template <typename T> void declToImport() {"
2970              "  S<T>::template foo<T>();"
2971              "}"
2972              "void instantiate() { declToImport<int>(); }",
2973              Lang_CXX11, "", Lang_CXX11, Verifier,
2974              functionTemplateDecl(has(functionDecl(has(compoundStmt(
2975                  has(callExpr(has(dependentScopeDeclRefExpr())))))))));
2976 }
2977 
2978 const internal::VariadicDynCastAllOfMatcher<Type, DependentNameType>
2979     dependentNameType;
2980 
2981 TEST_P(ImportExpr, DependentNameType) {
2982   MatchVerifier<Decl> Verifier;
2983   testImport("template <typename T> struct declToImport {"
2984              "  typedef typename T::type dependent_name;"
2985              "};",
2986              Lang_CXX11, "", Lang_CXX11, Verifier,
2987              classTemplateDecl(has(
2988                  cxxRecordDecl(has(typedefDecl(has(dependentNameType())))))));
2989 }
2990 
2991 TEST_P(ImportExpr, UnresolvedMemberExpr) {
2992   MatchVerifier<Decl> Verifier;
2993   testImport("struct S { template <typename T> void mem(); };"
2994              "template <typename U> void declToImport() {"
2995              "  S s;"
2996              "  s.mem<U>();"
2997              "}"
2998              "void instantiate() { declToImport<int>(); }",
2999              Lang_CXX11, "", Lang_CXX11, Verifier,
3000              functionTemplateDecl(has(functionDecl(has(
3001                  compoundStmt(has(callExpr(has(unresolvedMemberExpr())))))))));
3002 }
3003 
3004 class ImportImplicitMethods : public ASTImporterOptionSpecificTestBase {
3005 public:
3006   static constexpr auto DefaultCode = R"(
3007       struct A { int x; };
3008       void f() {
3009         A a;
3010         A a1(a);
3011         A a2(A{});
3012         a = a1;
3013         a = A{};
3014         a.~A();
3015       })";
3016 
3017   template <typename MatcherType>
3018   void testImportOf(
3019       const MatcherType &MethodMatcher, const char *Code = DefaultCode) {
3020     test(MethodMatcher, Code, /*ExpectedCount=*/1u);
3021   }
3022 
3023   template <typename MatcherType>
3024   void testNoImportOf(
3025       const MatcherType &MethodMatcher, const char *Code = DefaultCode) {
3026     test(MethodMatcher, Code, /*ExpectedCount=*/0u);
3027   }
3028 
3029 private:
3030   template <typename MatcherType>
3031   void test(const MatcherType &MethodMatcher,
3032       const char *Code, unsigned int ExpectedCount) {
3033     auto ClassMatcher = cxxRecordDecl(unless(isImplicit()));
3034 
3035     Decl *ToTU = getToTuDecl(Code, Lang_CXX11);
3036     auto *ToClass = FirstDeclMatcher<CXXRecordDecl>().match(
3037         ToTU, ClassMatcher);
3038 
3039     ASSERT_EQ(DeclCounter<CXXMethodDecl>().match(ToClass, MethodMatcher), 1u);
3040 
3041     {
3042       CXXMethodDecl *Method =
3043           FirstDeclMatcher<CXXMethodDecl>().match(ToClass, MethodMatcher);
3044       ToClass->removeDecl(Method);
3045       SharedStatePtr->getLookupTable()->remove(Method);
3046     }
3047 
3048     ASSERT_EQ(DeclCounter<CXXMethodDecl>().match(ToClass, MethodMatcher), 0u);
3049 
3050     Decl *ImportedClass = nullptr;
3051     {
3052       Decl *FromTU = getTuDecl(Code, Lang_CXX11, "input1.cc");
3053       auto *FromClass = FirstDeclMatcher<CXXRecordDecl>().match(
3054           FromTU, ClassMatcher);
3055       ImportedClass = Import(FromClass, Lang_CXX11);
3056     }
3057 
3058     EXPECT_EQ(ToClass, ImportedClass);
3059     EXPECT_EQ(DeclCounter<CXXMethodDecl>().match(ToClass, MethodMatcher),
3060         ExpectedCount);
3061   }
3062 };
3063 
3064 TEST_P(ImportImplicitMethods, DefaultConstructor) {
3065   testImportOf(cxxConstructorDecl(isDefaultConstructor()));
3066 }
3067 
3068 TEST_P(ImportImplicitMethods, CopyConstructor) {
3069   testImportOf(cxxConstructorDecl(isCopyConstructor()));
3070 }
3071 
3072 TEST_P(ImportImplicitMethods, MoveConstructor) {
3073   testImportOf(cxxConstructorDecl(isMoveConstructor()));
3074 }
3075 
3076 TEST_P(ImportImplicitMethods, Destructor) {
3077   testImportOf(cxxDestructorDecl());
3078 }
3079 
3080 TEST_P(ImportImplicitMethods, CopyAssignment) {
3081   testImportOf(cxxMethodDecl(isCopyAssignmentOperator()));
3082 }
3083 
3084 TEST_P(ImportImplicitMethods, MoveAssignment) {
3085   testImportOf(cxxMethodDecl(isMoveAssignmentOperator()));
3086 }
3087 
3088 TEST_P(ImportImplicitMethods, DoNotImportUserProvided) {
3089   auto Code = R"(
3090       struct A { A() { int x; } };
3091       )";
3092   testNoImportOf(cxxConstructorDecl(isDefaultConstructor()), Code);
3093 }
3094 
3095 TEST_P(ImportImplicitMethods, DoNotImportDefault) {
3096   auto Code = R"(
3097       struct A { A() = default; };
3098       )";
3099   testNoImportOf(cxxConstructorDecl(isDefaultConstructor()), Code);
3100 }
3101 
3102 TEST_P(ImportImplicitMethods, DoNotImportDeleted) {
3103   auto Code = R"(
3104       struct A { A() = delete; };
3105       )";
3106   testNoImportOf(cxxConstructorDecl(isDefaultConstructor()), Code);
3107 }
3108 
3109 TEST_P(ImportImplicitMethods, DoNotImportOtherMethod) {
3110   auto Code = R"(
3111       struct A { void f() { } };
3112       )";
3113   testNoImportOf(cxxMethodDecl(hasName("f")), Code);
3114 }
3115 
3116 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfEquivalentRecord) {
3117   Decl *ToR1;
3118   {
3119     Decl *FromTU = getTuDecl("struct A { };", Lang_CXX03, "input0.cc");
3120     auto *FromR = FirstDeclMatcher<CXXRecordDecl>().match(
3121         FromTU, cxxRecordDecl(hasName("A")));
3122 
3123     ToR1 = Import(FromR, Lang_CXX03);
3124   }
3125 
3126   Decl *ToR2;
3127   {
3128     Decl *FromTU = getTuDecl("struct A { };", Lang_CXX03, "input1.cc");
3129     auto *FromR = FirstDeclMatcher<CXXRecordDecl>().match(
3130         FromTU, cxxRecordDecl(hasName("A")));
3131 
3132     ToR2 = Import(FromR, Lang_CXX03);
3133   }
3134 
3135   EXPECT_EQ(ToR1, ToR2);
3136 }
3137 
3138 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfNonEquivalentRecord) {
3139   Decl *ToR1;
3140   {
3141     Decl *FromTU = getTuDecl("struct A { int x; };", Lang_CXX03, "input0.cc");
3142     auto *FromR = FirstDeclMatcher<CXXRecordDecl>().match(
3143         FromTU, cxxRecordDecl(hasName("A")));
3144     ToR1 = Import(FromR, Lang_CXX03);
3145   }
3146   Decl *ToR2;
3147   {
3148     Decl *FromTU =
3149         getTuDecl("struct A { unsigned x; };", Lang_CXX03, "input1.cc");
3150     auto *FromR = FirstDeclMatcher<CXXRecordDecl>().match(
3151         FromTU, cxxRecordDecl(hasName("A")));
3152     ToR2 = Import(FromR, Lang_CXX03);
3153   }
3154   EXPECT_NE(ToR1, ToR2);
3155 }
3156 
3157 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfEquivalentField) {
3158   Decl *ToF1;
3159   {
3160     Decl *FromTU = getTuDecl("struct A { int x; };", Lang_CXX03, "input0.cc");
3161     auto *FromF = FirstDeclMatcher<FieldDecl>().match(
3162         FromTU, fieldDecl(hasName("x")));
3163     ToF1 = Import(FromF, Lang_CXX03);
3164   }
3165   Decl *ToF2;
3166   {
3167     Decl *FromTU = getTuDecl("struct A { int x; };", Lang_CXX03, "input1.cc");
3168     auto *FromF = FirstDeclMatcher<FieldDecl>().match(
3169         FromTU, fieldDecl(hasName("x")));
3170     ToF2 = Import(FromF, Lang_CXX03);
3171   }
3172   EXPECT_EQ(ToF1, ToF2);
3173 }
3174 
3175 TEST_P(ASTImporterOptionSpecificTestBase, ImportBitfields) {
3176   Decl *FromTU = getTuDecl("struct A { unsigned x : 3; };", Lang_CXX03);
3177   auto *FromF =
3178       FirstDeclMatcher<FieldDecl>().match(FromTU, fieldDecl(hasName("x")));
3179 
3180   ASSERT_TRUE(FromF->isBitField());
3181   ASSERT_EQ(3u, FromF->getBitWidthValue(FromTU->getASTContext()));
3182   auto *ToField = Import(FromF, Lang_CXX03);
3183   auto *ToTU = ToField->getTranslationUnitDecl();
3184 
3185   EXPECT_TRUE(ToField->isBitField());
3186   EXPECT_EQ(3u, ToField->getBitWidthValue(ToTU->getASTContext()));
3187 
3188   const auto *FromBT = FromF->getBitWidth()->getType()->getAs<BuiltinType>();
3189   const auto *ToBT = ToField->getBitWidth()->getType()->getAs<BuiltinType>();
3190   ASSERT_TRUE(FromBT);
3191   ASSERT_EQ(BuiltinType::Int, FromBT->getKind());
3192   EXPECT_TRUE(ToBT);
3193   EXPECT_EQ(BuiltinType::Int, ToBT->getKind());
3194 }
3195 
3196 struct ImportBlock : ASTImporterOptionSpecificTestBase {};
3197 TEST_P(ImportBlock, ImportBlocksAreUnsupported) {
3198   const auto *Code = R"(
3199     void test_block__capture_null() {
3200       int *p = 0;
3201       ^(){
3202         *p = 1;
3203       }();
3204     })";
3205   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
3206   auto *FromBlock = FirstDeclMatcher<BlockDecl>().match(FromTU, blockDecl());
3207   ASSERT_TRUE(FromBlock);
3208 
3209   auto ToBlockOrError = importOrError(FromBlock, Lang_CXX03);
3210 
3211   const auto ExpectUnsupportedConstructError = [](const ASTImportError &Error) {
3212     EXPECT_EQ(ASTImportError::UnsupportedConstruct, Error.Error);
3213   };
3214   llvm::handleAllErrors(ToBlockOrError.takeError(),
3215                         ExpectUnsupportedConstructError);
3216 }
3217 
3218 TEST_P(ASTImporterOptionSpecificTestBase, ImportParmVarDecl) {
3219   const auto *Code = R"(
3220     template <typename T> struct Wrapper {
3221       Wrapper(T Value = {}) {}
3222     };
3223     template class Wrapper<int>;
3224     )";
3225   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
3226   auto *FromVar = FirstDeclMatcher<ParmVarDecl>().match(
3227       FromTU, parmVarDecl(hasType(asString("int"))));
3228   ASSERT_TRUE(FromVar);
3229   ASSERT_TRUE(FromVar->hasUninstantiatedDefaultArg());
3230   ASSERT_TRUE(FromVar->getUninstantiatedDefaultArg());
3231 
3232   const auto *ToVar = Import(FromVar, Lang_CXX11);
3233   EXPECT_TRUE(ToVar);
3234   EXPECT_TRUE(ToVar->hasUninstantiatedDefaultArg());
3235   EXPECT_TRUE(ToVar->getUninstantiatedDefaultArg());
3236   EXPECT_NE(FromVar->getUninstantiatedDefaultArg(),
3237             ToVar->getUninstantiatedDefaultArg());
3238 }
3239 
3240 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfNonEquivalentField) {
3241   Decl *ToF1;
3242   {
3243     Decl *FromTU = getTuDecl("struct A { int x; };", Lang_CXX03, "input0.cc");
3244     auto *FromF = FirstDeclMatcher<FieldDecl>().match(
3245         FromTU, fieldDecl(hasName("x")));
3246     ToF1 = Import(FromF, Lang_CXX03);
3247   }
3248   Decl *ToF2;
3249   {
3250     Decl *FromTU =
3251         getTuDecl("struct A { unsigned x; };", Lang_CXX03, "input1.cc");
3252     auto *FromF = FirstDeclMatcher<FieldDecl>().match(
3253         FromTU, fieldDecl(hasName("x")));
3254     ToF2 = Import(FromF, Lang_CXX03);
3255   }
3256   EXPECT_NE(ToF1, ToF2);
3257 }
3258 
3259 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfEquivalentMethod) {
3260   Decl *ToM1;
3261   {
3262     Decl *FromTU = getTuDecl("struct A { void x(); }; void A::x() { }",
3263                              Lang_CXX03, "input0.cc");
3264     auto *FromM = FirstDeclMatcher<FunctionDecl>().match(
3265         FromTU, functionDecl(hasName("x"), isDefinition()));
3266     ToM1 = Import(FromM, Lang_CXX03);
3267   }
3268   Decl *ToM2;
3269   {
3270     Decl *FromTU = getTuDecl("struct A { void x(); }; void A::x() { }",
3271                              Lang_CXX03, "input1.cc");
3272     auto *FromM = FirstDeclMatcher<FunctionDecl>().match(
3273         FromTU, functionDecl(hasName("x"), isDefinition()));
3274     ToM2 = Import(FromM, Lang_CXX03);
3275   }
3276   EXPECT_EQ(ToM1, ToM2);
3277 }
3278 
3279 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfNonEquivalentMethod) {
3280   Decl *ToM1;
3281   {
3282     Decl *FromTU = getTuDecl("struct A { void x(); }; void A::x() { }",
3283                              Lang_CXX03, "input0.cc");
3284     auto *FromM = FirstDeclMatcher<FunctionDecl>().match(
3285         FromTU, functionDecl(hasName("x"), isDefinition()));
3286     ToM1 = Import(FromM, Lang_CXX03);
3287   }
3288   Decl *ToM2;
3289   {
3290     Decl *FromTU =
3291         getTuDecl("struct A { void x() const; }; void A::x() const { }",
3292                   Lang_CXX03, "input1.cc");
3293     auto *FromM = FirstDeclMatcher<FunctionDecl>().match(
3294         FromTU, functionDecl(hasName("x"), isDefinition()));
3295     ToM2 = Import(FromM, Lang_CXX03);
3296   }
3297   EXPECT_NE(ToM1, ToM2);
3298 }
3299 
3300 TEST_P(ASTImporterOptionSpecificTestBase,
3301        ImportUnnamedStructsWithRecursingField) {
3302   Decl *FromTU = getTuDecl(
3303       R"(
3304       struct A {
3305         struct {
3306           struct A *next;
3307         } entry0;
3308         struct {
3309           struct A *next;
3310         } entry1;
3311       };
3312       )",
3313       Lang_C99, "input0.cc");
3314   auto *From =
3315       FirstDeclMatcher<RecordDecl>().match(FromTU, recordDecl(hasName("A")));
3316 
3317   Import(From, Lang_C99);
3318 
3319   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
3320   auto *Entry0 =
3321       FirstDeclMatcher<FieldDecl>().match(ToTU, fieldDecl(hasName("entry0")));
3322   auto *Entry1 =
3323       FirstDeclMatcher<FieldDecl>().match(ToTU, fieldDecl(hasName("entry1")));
3324   auto *R0 = getRecordDecl(Entry0);
3325   auto *R1 = getRecordDecl(Entry1);
3326   EXPECT_NE(R0, R1);
3327   EXPECT_TRUE(MatchVerifier<RecordDecl>().match(
3328       R0, recordDecl(has(fieldDecl(hasName("next"))))));
3329   EXPECT_TRUE(MatchVerifier<RecordDecl>().match(
3330       R1, recordDecl(has(fieldDecl(hasName("next"))))));
3331 }
3332 
3333 TEST_P(ASTImporterOptionSpecificTestBase, ImportUnnamedFieldsInCorrectOrder) {
3334   Decl *FromTU = getTuDecl(
3335       R"(
3336       void f(int X, int Y, bool Z) {
3337         (void)[X, Y, Z] { (void)Z; };
3338       }
3339       )",
3340       Lang_CXX11, "input0.cc");
3341   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
3342       FromTU, functionDecl(hasName("f")));
3343   auto *ToF = cast_or_null<FunctionDecl>(Import(FromF, Lang_CXX11));
3344   EXPECT_TRUE(ToF);
3345 
3346   CXXRecordDecl *FromLambda =
3347       cast<LambdaExpr>(cast<CStyleCastExpr>(cast<CompoundStmt>(
3348           FromF->getBody())->body_front())->getSubExpr())->getLambdaClass();
3349 
3350   auto *ToLambda = cast_or_null<CXXRecordDecl>(Import(FromLambda, Lang_CXX11));
3351   EXPECT_TRUE(ToLambda);
3352 
3353   // Check if the fields of the lambda class are imported in correct order.
3354   unsigned FromIndex = 0u;
3355   for (auto *FromField : FromLambda->fields()) {
3356     ASSERT_FALSE(FromField->getDeclName());
3357     auto *ToField = cast_or_null<FieldDecl>(Import(FromField, Lang_CXX11));
3358     EXPECT_TRUE(ToField);
3359     Optional<unsigned> ToIndex = ASTImporter::getFieldIndex(ToField);
3360     EXPECT_TRUE(ToIndex);
3361     EXPECT_EQ(*ToIndex, FromIndex);
3362     ++FromIndex;
3363   }
3364 
3365   EXPECT_EQ(FromIndex, 3u);
3366 }
3367 
3368 TEST_P(ASTImporterOptionSpecificTestBase,
3369        MergeFieldDeclsOfClassTemplateSpecialization) {
3370   std::string ClassTemplate =
3371       R"(
3372       template <typename T>
3373       struct X {
3374           int a{0}; // FieldDecl with InitListExpr
3375           X(char) : a(3) {}     // (1)
3376           X(int) {}             // (2)
3377       };
3378       )";
3379   Decl *ToTU = getToTuDecl(ClassTemplate +
3380       R"(
3381       void foo() {
3382           // ClassTemplateSpec with ctor (1): FieldDecl without InitlistExpr
3383           X<char> xc('c');
3384       }
3385       )", Lang_CXX11);
3386   auto *ToSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3387       ToTU, classTemplateSpecializationDecl(hasName("X")));
3388   // FieldDecl without InitlistExpr:
3389   auto *ToField = *ToSpec->field_begin();
3390   ASSERT_TRUE(ToField);
3391   ASSERT_FALSE(ToField->getInClassInitializer());
3392   Decl *FromTU = getTuDecl(ClassTemplate +
3393       R"(
3394       void bar() {
3395           // ClassTemplateSpec with ctor (2): FieldDecl WITH InitlistExpr
3396           X<char> xc(1);
3397       }
3398       )", Lang_CXX11);
3399   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3400       FromTU, classTemplateSpecializationDecl(hasName("X")));
3401   // FieldDecl with InitlistExpr:
3402   auto *FromField = *FromSpec->field_begin();
3403   ASSERT_TRUE(FromField);
3404   ASSERT_TRUE(FromField->getInClassInitializer());
3405 
3406   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3407   ASSERT_TRUE(ImportedSpec);
3408   EXPECT_EQ(ImportedSpec, ToSpec);
3409   // After the import, the FieldDecl has to be merged, thus it should have the
3410   // InitListExpr.
3411   EXPECT_TRUE(ToField->getInClassInitializer());
3412 }
3413 
3414 TEST_P(ASTImporterOptionSpecificTestBase,
3415        MergeFunctionOfClassTemplateSpecialization) {
3416   std::string ClassTemplate =
3417       R"(
3418       template <typename T>
3419       struct X {
3420         void f() {}
3421         void g() {}
3422       };
3423       )";
3424   Decl *ToTU = getToTuDecl(ClassTemplate +
3425       R"(
3426       void foo() {
3427           X<char> x;
3428           x.f();
3429       }
3430       )", Lang_CXX11);
3431   Decl *FromTU = getTuDecl(ClassTemplate +
3432       R"(
3433       void bar() {
3434           X<char> x;
3435           x.g();
3436       }
3437       )", Lang_CXX11);
3438   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3439       FromTU, classTemplateSpecializationDecl(hasName("X")));
3440   auto FunPattern = functionDecl(hasName("g"),
3441                          hasParent(classTemplateSpecializationDecl()));
3442   auto *FromFun =
3443       FirstDeclMatcher<FunctionDecl>().match(FromTU, FunPattern);
3444   auto *ToFun =
3445       FirstDeclMatcher<FunctionDecl>().match(ToTU, FunPattern);
3446   ASSERT_TRUE(FromFun->hasBody());
3447   ASSERT_FALSE(ToFun->hasBody());
3448   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3449   ASSERT_TRUE(ImportedSpec);
3450   auto *ToSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3451       ToTU, classTemplateSpecializationDecl(hasName("X")));
3452   EXPECT_EQ(ImportedSpec, ToSpec);
3453   EXPECT_TRUE(ToFun->hasBody());
3454 }
3455 
3456 TEST_P(ASTImporterOptionSpecificTestBase, MergeTemplateSpecWithForwardDecl) {
3457   std::string ClassTemplate =
3458       R"(
3459       template<typename T>
3460       struct X { int m; };
3461       template<>
3462       struct X<int> { int m; };
3463       )";
3464   // Append a forward decl for our template specialization.
3465   getToTuDecl(ClassTemplate + "template<> struct X<int>;", Lang_CXX11);
3466   Decl *FromTU = getTuDecl(ClassTemplate, Lang_CXX11);
3467   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3468       FromTU, classTemplateSpecializationDecl(hasName("X"), isDefinition()));
3469   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3470   // Check that our definition got merged with the existing definition.
3471   EXPECT_TRUE(FromSpec->isThisDeclarationADefinition());
3472   EXPECT_TRUE(ImportedSpec->isThisDeclarationADefinition());
3473 }
3474 
3475 TEST_P(ASTImporterOptionSpecificTestBase,
3476        ODRViolationOfClassTemplateSpecializationsShouldBeReported) {
3477   std::string ClassTemplate =
3478       R"(
3479       template <typename T>
3480       struct X {};
3481       )";
3482   Decl *ToTU = getToTuDecl(ClassTemplate +
3483                                R"(
3484       template <>
3485       struct X<char> {
3486           int a;
3487       };
3488       void foo() {
3489           X<char> x;
3490       }
3491       )",
3492                            Lang_CXX11);
3493   Decl *FromTU = getTuDecl(ClassTemplate +
3494                                R"(
3495       template <>
3496       struct X<char> {
3497           int b;
3498       };
3499       void foo() {
3500           X<char> x;
3501       }
3502       )",
3503                            Lang_CXX11);
3504   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3505       FromTU, classTemplateSpecializationDecl(hasName("X")));
3506   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3507 
3508   // We expect one (ODR) warning during the import.
3509   EXPECT_EQ(1u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
3510 
3511   // The second specialization is different from the first, thus it violates
3512   // ODR, consequently we expect to keep the first specialization only, which is
3513   // already in the "To" context.
3514   EXPECT_FALSE(ImportedSpec);
3515   EXPECT_EQ(1u,
3516             DeclCounter<ClassTemplateSpecializationDecl>().match(
3517                 ToTU, classTemplateSpecializationDecl(hasName("X"))));
3518 }
3519 
3520 TEST_P(ASTImporterOptionSpecificTestBase,
3521        MergeCtorOfClassTemplateSpecialization) {
3522   std::string ClassTemplate =
3523       R"(
3524       template <typename T>
3525       struct X {
3526           X(char) {}
3527           X(int) {}
3528       };
3529       )";
3530   Decl *ToTU = getToTuDecl(ClassTemplate +
3531       R"(
3532       void foo() {
3533           X<char> x('c');
3534       }
3535       )", Lang_CXX11);
3536   Decl *FromTU = getTuDecl(ClassTemplate +
3537       R"(
3538       void bar() {
3539           X<char> x(1);
3540       }
3541       )", Lang_CXX11);
3542   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3543       FromTU, classTemplateSpecializationDecl(hasName("X")));
3544   // Match the void(int) ctor.
3545   auto CtorPattern =
3546       cxxConstructorDecl(hasParameter(0, varDecl(hasType(asString("int")))),
3547                          hasParent(classTemplateSpecializationDecl()));
3548   auto *FromCtor =
3549       FirstDeclMatcher<CXXConstructorDecl>().match(FromTU, CtorPattern);
3550   auto *ToCtor =
3551       FirstDeclMatcher<CXXConstructorDecl>().match(ToTU, CtorPattern);
3552   ASSERT_TRUE(FromCtor->hasBody());
3553   ASSERT_FALSE(ToCtor->hasBody());
3554   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3555   ASSERT_TRUE(ImportedSpec);
3556   auto *ToSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3557       ToTU, classTemplateSpecializationDecl(hasName("X")));
3558   EXPECT_EQ(ImportedSpec, ToSpec);
3559   EXPECT_TRUE(ToCtor->hasBody());
3560 }
3561 
3562 TEST_P(ASTImporterOptionSpecificTestBase, ClassTemplateFriendDecl) {
3563   const auto *Code =
3564       R"(
3565       template <class T> class X {  friend T; };
3566       struct Y {};
3567       template class X<Y>;
3568     )";
3569   Decl *ToTU = getToTuDecl(Code, Lang_CXX11);
3570   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
3571   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3572       FromTU, classTemplateSpecializationDecl());
3573   auto *ToSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3574       ToTU, classTemplateSpecializationDecl());
3575 
3576   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3577   EXPECT_EQ(ImportedSpec, ToSpec);
3578   EXPECT_EQ(1u, DeclCounter<ClassTemplateSpecializationDecl>().match(
3579                     ToTU, classTemplateSpecializationDecl()));
3580 }
3581 
3582 TEST_P(ASTImporterOptionSpecificTestBase,
3583        ClassTemplatePartialSpecializationsShouldNotBeDuplicated) {
3584   auto Code =
3585       R"(
3586     // primary template
3587     template<class T1, class T2, int I>
3588     class A {};
3589 
3590     // partial specialization
3591     template<class T, int I>
3592     class A<T, T*, I> {};
3593     )";
3594   Decl *ToTU = getToTuDecl(Code, Lang_CXX11);
3595   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
3596   auto *FromSpec =
3597       FirstDeclMatcher<ClassTemplatePartialSpecializationDecl>().match(
3598           FromTU, classTemplatePartialSpecializationDecl());
3599   auto *ToSpec =
3600       FirstDeclMatcher<ClassTemplatePartialSpecializationDecl>().match(
3601           ToTU, classTemplatePartialSpecializationDecl());
3602 
3603   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3604   EXPECT_EQ(ImportedSpec, ToSpec);
3605   EXPECT_EQ(1u, DeclCounter<ClassTemplatePartialSpecializationDecl>().match(
3606                     ToTU, classTemplatePartialSpecializationDecl()));
3607 }
3608 
3609 TEST_P(ASTImporterOptionSpecificTestBase,
3610        ClassTemplateSpecializationsShouldNotBeDuplicated) {
3611   auto Code =
3612       R"(
3613     // primary template
3614     template<class T1, class T2, int I>
3615     class A {};
3616 
3617     // full specialization
3618     template<>
3619     class A<int, int, 1> {};
3620     )";
3621   Decl *ToTU = getToTuDecl(Code, Lang_CXX11);
3622   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
3623   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3624       FromTU, classTemplateSpecializationDecl());
3625   auto *ToSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3626       ToTU, classTemplateSpecializationDecl());
3627 
3628   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3629   EXPECT_EQ(ImportedSpec, ToSpec);
3630   EXPECT_EQ(1u, DeclCounter<ClassTemplateSpecializationDecl>().match(
3631                    ToTU, classTemplateSpecializationDecl()));
3632 }
3633 
3634 TEST_P(ASTImporterOptionSpecificTestBase,
3635        ClassTemplateFullAndPartialSpecsShouldNotBeMixed) {
3636   std::string PrimaryTemplate =
3637       R"(
3638     template<class T1, class T2, int I>
3639     class A {};
3640     )";
3641   auto PartialSpec =
3642       R"(
3643     template<class T, int I>
3644     class A<T, T*, I> {};
3645     )";
3646   auto FullSpec =
3647       R"(
3648     template<>
3649     class A<int, int, 1> {};
3650     )";
3651   Decl *ToTU = getToTuDecl(PrimaryTemplate + FullSpec, Lang_CXX11);
3652   Decl *FromTU = getTuDecl(PrimaryTemplate + PartialSpec, Lang_CXX11);
3653   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
3654       FromTU, classTemplateSpecializationDecl());
3655 
3656   auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
3657   EXPECT_TRUE(ImportedSpec);
3658   // Check the number of partial specializations.
3659   EXPECT_EQ(1u, DeclCounter<ClassTemplatePartialSpecializationDecl>().match(
3660                     ToTU, classTemplatePartialSpecializationDecl()));
3661   // Check the number of full specializations.
3662   EXPECT_EQ(1u, DeclCounter<ClassTemplateSpecializationDecl>().match(
3663                     ToTU, classTemplateSpecializationDecl(
3664                               unless(classTemplatePartialSpecializationDecl()))));
3665 }
3666 
3667 TEST_P(ASTImporterOptionSpecificTestBase,
3668        InitListExprValueKindShouldBeImported) {
3669   Decl *TU = getTuDecl(
3670       R"(
3671       const int &init();
3672       void foo() { const int &a{init()}; }
3673       )", Lang_CXX11, "input0.cc");
3674   auto *FromD = FirstDeclMatcher<VarDecl>().match(TU, varDecl(hasName("a")));
3675   ASSERT_TRUE(FromD->getAnyInitializer());
3676   auto *InitExpr = FromD->getAnyInitializer();
3677   ASSERT_TRUE(InitExpr);
3678   ASSERT_TRUE(InitExpr->isGLValue());
3679 
3680   auto *ToD = Import(FromD, Lang_CXX11);
3681   EXPECT_TRUE(ToD);
3682   auto *ToInitExpr = cast<VarDecl>(ToD)->getAnyInitializer();
3683   EXPECT_TRUE(ToInitExpr);
3684   EXPECT_TRUE(ToInitExpr->isGLValue());
3685 }
3686 
3687 struct ImportVariables : ASTImporterOptionSpecificTestBase {};
3688 
3689 TEST_P(ImportVariables, ImportOfOneDeclBringsInTheWholeChain) {
3690   Decl *FromTU = getTuDecl(
3691       R"(
3692       struct A {
3693         static const int a = 1 + 2;
3694       };
3695       const int A::a;
3696       )",
3697       Lang_CXX03, "input1.cc");
3698 
3699   auto *FromDWithInit = FirstDeclMatcher<VarDecl>().match(
3700       FromTU, varDecl(hasName("a"))); // Decl with init
3701   auto *FromDWithDef = LastDeclMatcher<VarDecl>().match(
3702       FromTU, varDecl(hasName("a"))); // Decl with definition
3703   ASSERT_NE(FromDWithInit, FromDWithDef);
3704   ASSERT_EQ(FromDWithDef->getPreviousDecl(), FromDWithInit);
3705 
3706   auto *ToD0 = cast<VarDecl>(Import(FromDWithInit, Lang_CXX11));
3707   auto *ToD1 = cast<VarDecl>(Import(FromDWithDef, Lang_CXX11));
3708   ASSERT_TRUE(ToD0);
3709   ASSERT_TRUE(ToD1);
3710   EXPECT_NE(ToD0, ToD1);
3711   EXPECT_EQ(ToD1->getPreviousDecl(), ToD0);
3712 }
3713 
3714 TEST_P(ImportVariables, InitAndDefinitionAreInDifferentTUs) {
3715   auto StructA =
3716       R"(
3717       struct A {
3718         static const int a = 1 + 2;
3719       };
3720       )";
3721   Decl *ToTU = getToTuDecl(StructA, Lang_CXX03);
3722   Decl *FromTU = getTuDecl(std::string(StructA) + "const int A::a;", Lang_CXX03,
3723                            "input1.cc");
3724 
3725   auto *FromDWithInit = FirstDeclMatcher<VarDecl>().match(
3726       FromTU, varDecl(hasName("a"))); // Decl with init
3727   auto *FromDWithDef = LastDeclMatcher<VarDecl>().match(
3728       FromTU, varDecl(hasName("a"))); // Decl with definition
3729   ASSERT_EQ(FromDWithInit, FromDWithDef->getPreviousDecl());
3730   ASSERT_TRUE(FromDWithInit->getInit());
3731   ASSERT_FALSE(FromDWithInit->isThisDeclarationADefinition());
3732   ASSERT_TRUE(FromDWithDef->isThisDeclarationADefinition());
3733   ASSERT_FALSE(FromDWithDef->getInit());
3734 
3735   auto *ToD = FirstDeclMatcher<VarDecl>().match(
3736       ToTU, varDecl(hasName("a"))); // Decl with init
3737   ASSERT_TRUE(ToD->getInit());
3738   ASSERT_FALSE(ToD->getDefinition());
3739 
3740   auto *ImportedD = cast<VarDecl>(Import(FromDWithDef, Lang_CXX11));
3741   EXPECT_TRUE(ImportedD->getAnyInitializer());
3742   EXPECT_TRUE(ImportedD->getDefinition());
3743 }
3744 
3745 TEST_P(ImportVariables, InitAndDefinitionAreInTheFromContext) {
3746   auto StructA =
3747       R"(
3748       struct A {
3749         static const int a;
3750       };
3751       )";
3752   Decl *ToTU = getToTuDecl(StructA, Lang_CXX03);
3753   Decl *FromTU = getTuDecl(std::string(StructA) + "const int A::a = 1 + 2;",
3754                            Lang_CXX03, "input1.cc");
3755 
3756   auto *FromDDeclarationOnly = FirstDeclMatcher<VarDecl>().match(
3757       FromTU, varDecl(hasName("a")));
3758   auto *FromDWithDef = LastDeclMatcher<VarDecl>().match(
3759       FromTU, varDecl(hasName("a"))); // Decl with definition and with init.
3760   ASSERT_EQ(FromDDeclarationOnly, FromDWithDef->getPreviousDecl());
3761   ASSERT_FALSE(FromDDeclarationOnly->getInit());
3762   ASSERT_FALSE(FromDDeclarationOnly->isThisDeclarationADefinition());
3763   ASSERT_TRUE(FromDWithDef->isThisDeclarationADefinition());
3764   ASSERT_TRUE(FromDWithDef->getInit());
3765 
3766   auto *ToD = FirstDeclMatcher<VarDecl>().match(
3767       ToTU, varDecl(hasName("a")));
3768   ASSERT_FALSE(ToD->getInit());
3769   ASSERT_FALSE(ToD->getDefinition());
3770 
3771   auto *ImportedD = cast<VarDecl>(Import(FromDWithDef, Lang_CXX11));
3772   EXPECT_TRUE(ImportedD->getAnyInitializer());
3773   EXPECT_TRUE(ImportedD->getDefinition());
3774 }
3775 
3776 TEST_P(ImportVariables, ImportBindingDecl) {
3777   Decl *From, *To;
3778   std::tie(From, To) = getImportedDecl(
3779       R"(
3780       void declToImport() {
3781         int a[2] = {1,2};
3782         auto [x1,y1] = a;
3783         auto& [x2,y2] = a;
3784 
3785         struct S {
3786           mutable int x1 : 2;
3787           volatile double y1;
3788         };
3789         S b;
3790         const auto [x3, y3] = b;
3791       };
3792       )",
3793       Lang_CXX17, "", Lang_CXX17);
3794 
3795   TranslationUnitDecl *FromTU = From->getTranslationUnitDecl();
3796   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
3797       FromTU, functionDecl(hasName("declToImport")));
3798   auto *ToF = Import(FromF, Lang_CXX17);
3799   EXPECT_TRUE(ToF);
3800 
3801   auto VerifyImport = [&](llvm::StringRef BindName) {
3802     auto *FromB = FirstDeclMatcher<BindingDecl>().match(
3803         FromF, bindingDecl(hasName(BindName)));
3804     ASSERT_TRUE(FromB);
3805     auto *ToB = Import(FromB, Lang_CXX17);
3806     EXPECT_TRUE(ToB);
3807     EXPECT_EQ(FromB->getBinding() != nullptr, ToB->getBinding() != nullptr);
3808     EXPECT_EQ(FromB->getDecomposedDecl() != nullptr,
3809               ToB->getDecomposedDecl() != nullptr);
3810     EXPECT_EQ(FromB->getHoldingVar() != nullptr,
3811               ToB->getHoldingVar() != nullptr);
3812   };
3813 
3814   VerifyImport("x1");
3815   VerifyImport("y1");
3816   VerifyImport("x2");
3817   VerifyImport("y2");
3818   VerifyImport("x3");
3819   VerifyImport("y3");
3820 }
3821 
3822 TEST_P(ImportVariables, ImportDecompositionDeclArray) {
3823   Decl *From, *To;
3824   std::tie(From, To) = getImportedDecl(
3825       R"(
3826       void declToImport() {
3827         int a[2] = {1,2};
3828         auto [x1,y1] = a;
3829       };
3830       )",
3831       Lang_CXX17, "", Lang_CXX17);
3832 
3833   TranslationUnitDecl *FromTU = From->getTranslationUnitDecl();
3834   auto *FromDecomp =
3835       FirstDeclMatcher<DecompositionDecl>().match(FromTU, decompositionDecl());
3836   auto *ToDecomp = Import(FromDecomp, Lang_CXX17);
3837   EXPECT_TRUE(ToDecomp);
3838 
3839   ArrayRef<BindingDecl *> FromB = FromDecomp->bindings();
3840   ArrayRef<BindingDecl *> ToB = ToDecomp->bindings();
3841   EXPECT_EQ(FromB.size(), ToB.size());
3842   for (unsigned int I = 0; I < FromB.size(); ++I) {
3843     auto *ToBI = Import(FromB[I], Lang_CXX17);
3844     EXPECT_EQ(ToBI, ToB[I]);
3845   }
3846 }
3847 
3848 struct ImportClasses : ASTImporterOptionSpecificTestBase {};
3849 
3850 TEST_P(ImportClasses, ImportDefinitionWhenProtoIsInNestedToContext) {
3851   Decl *ToTU = getToTuDecl("struct A { struct X *Xp; };", Lang_C99);
3852   Decl *FromTU1 = getTuDecl("struct X {};", Lang_C99, "input1.cc");
3853   auto Pattern = recordDecl(hasName("X"), unless(isImplicit()));
3854   auto ToProto = FirstDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3855   auto FromDef = FirstDeclMatcher<RecordDecl>().match(FromTU1, Pattern);
3856 
3857   Decl *ImportedDef = Import(FromDef, Lang_C99);
3858 
3859   EXPECT_NE(ImportedDef, ToProto);
3860   EXPECT_EQ(DeclCounter<RecordDecl>().match(ToTU, Pattern), 2u);
3861   auto ToDef = LastDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3862   EXPECT_TRUE(ImportedDef == ToDef);
3863   EXPECT_TRUE(ToDef->isThisDeclarationADefinition());
3864   EXPECT_FALSE(ToProto->isThisDeclarationADefinition());
3865   EXPECT_EQ(ToDef->getPreviousDecl(), ToProto);
3866 }
3867 
3868 TEST_P(ImportClasses, ImportDefinitionWhenProtoIsInNestedToContextCXX) {
3869   Decl *ToTU = getToTuDecl("struct A { struct X *Xp; };", Lang_CXX03);
3870   Decl *FromTU1 = getTuDecl("struct X {};", Lang_CXX03, "input1.cc");
3871   auto Pattern = recordDecl(hasName("X"), unless(isImplicit()));
3872   auto ToProto = FirstDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3873   auto FromDef = FirstDeclMatcher<RecordDecl>().match(FromTU1, Pattern);
3874 
3875   Decl *ImportedDef = Import(FromDef, Lang_CXX03);
3876 
3877   EXPECT_NE(ImportedDef, ToProto);
3878   EXPECT_EQ(DeclCounter<RecordDecl>().match(ToTU, Pattern), 2u);
3879   auto ToDef = LastDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3880   EXPECT_TRUE(ImportedDef == ToDef);
3881   EXPECT_TRUE(ToDef->isThisDeclarationADefinition());
3882   EXPECT_FALSE(ToProto->isThisDeclarationADefinition());
3883   EXPECT_EQ(ToDef->getPreviousDecl(), ToProto);
3884 }
3885 
3886 TEST_P(ImportClasses, ImportNestedPrototypeThenDefinition) {
3887   Decl *FromTU0 =
3888       getTuDecl("struct A { struct X *Xp; };", Lang_C99, "input0.cc");
3889   Decl *FromTU1 = getTuDecl("struct X {};", Lang_C99, "input1.cc");
3890   auto Pattern = recordDecl(hasName("X"), unless(isImplicit()));
3891   auto FromProto = FirstDeclMatcher<RecordDecl>().match(FromTU0, Pattern);
3892   auto FromDef = FirstDeclMatcher<RecordDecl>().match(FromTU1, Pattern);
3893 
3894   Decl *ImportedProto = Import(FromProto, Lang_C99);
3895   Decl *ImportedDef = Import(FromDef, Lang_C99);
3896   Decl *ToTU = ImportedDef->getTranslationUnitDecl();
3897 
3898   EXPECT_NE(ImportedDef, ImportedProto);
3899   EXPECT_EQ(DeclCounter<RecordDecl>().match(ToTU, Pattern), 2u);
3900   auto ToProto = FirstDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3901   auto ToDef = LastDeclMatcher<RecordDecl>().match(ToTU, Pattern);
3902   EXPECT_TRUE(ImportedDef == ToDef);
3903   EXPECT_TRUE(ImportedProto == ToProto);
3904   EXPECT_TRUE(ToDef->isThisDeclarationADefinition());
3905   EXPECT_FALSE(ToProto->isThisDeclarationADefinition());
3906   EXPECT_EQ(ToDef->getPreviousDecl(), ToProto);
3907 }
3908 
3909 
3910 struct ImportFriendClasses : ASTImporterOptionSpecificTestBase {};
3911 
3912 TEST_P(ImportFriendClasses, ImportOfFriendRecordDoesNotMergeDefinition) {
3913   Decl *FromTU = getTuDecl(
3914       R"(
3915       class A {
3916         template <int I> class F {};
3917         class X {
3918           template <int I> friend class F;
3919         };
3920       };
3921       )",
3922       Lang_CXX03, "input0.cc");
3923 
3924   auto *FromClass = FirstDeclMatcher<CXXRecordDecl>().match(
3925       FromTU, cxxRecordDecl(hasName("F"), isDefinition()));
3926   auto *FromFriendClass = LastDeclMatcher<CXXRecordDecl>().match(
3927       FromTU, cxxRecordDecl(hasName("F")));
3928 
3929   ASSERT_TRUE(FromClass);
3930   ASSERT_TRUE(FromFriendClass);
3931   ASSERT_NE(FromClass, FromFriendClass);
3932   ASSERT_EQ(FromFriendClass->getDefinition(), FromClass);
3933   ASSERT_EQ(FromFriendClass->getPreviousDecl(), FromClass);
3934   ASSERT_EQ(FromFriendClass->getDescribedClassTemplate()->getPreviousDecl(),
3935             FromClass->getDescribedClassTemplate());
3936 
3937   auto *ToClass = cast<CXXRecordDecl>(Import(FromClass, Lang_CXX03));
3938   auto *ToFriendClass =
3939       cast<CXXRecordDecl>(Import(FromFriendClass, Lang_CXX03));
3940 
3941   EXPECT_TRUE(ToClass);
3942   EXPECT_TRUE(ToFriendClass);
3943   EXPECT_NE(ToClass, ToFriendClass);
3944   EXPECT_EQ(ToFriendClass->getDefinition(), ToClass);
3945   EXPECT_EQ(ToFriendClass->getPreviousDecl(), ToClass);
3946   EXPECT_EQ(ToFriendClass->getDescribedClassTemplate()->getPreviousDecl(),
3947             ToClass->getDescribedClassTemplate());
3948 }
3949 
3950 TEST_P(ImportFriendClasses, ImportOfRecursiveFriendClass) {
3951   Decl *FromTu = getTuDecl(
3952       R"(
3953       class declToImport {
3954         friend class declToImport;
3955       };
3956       )",
3957       Lang_CXX03, "input.cc");
3958 
3959   auto *FromD = FirstDeclMatcher<CXXRecordDecl>().match(
3960       FromTu, cxxRecordDecl(hasName("declToImport")));
3961   auto *ToD = Import(FromD, Lang_CXX03);
3962   auto Pattern = cxxRecordDecl(has(friendDecl()));
3963   ASSERT_TRUE(MatchVerifier<Decl>{}.match(FromD, Pattern));
3964   EXPECT_TRUE(MatchVerifier<Decl>{}.match(ToD, Pattern));
3965 }
3966 
3967 TEST_P(ImportFriendClasses, UndeclaredFriendClassShouldNotBeVisible) {
3968   Decl *FromTu =
3969       getTuDecl("class X { friend class Y; };", Lang_CXX03, "from.cc");
3970   auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
3971       FromTu, cxxRecordDecl(hasName("X")));
3972   auto *FromFriend = FirstDeclMatcher<FriendDecl>().match(FromTu, friendDecl());
3973   RecordDecl *FromRecordOfFriend =
3974       const_cast<RecordDecl *>(getRecordDeclOfFriend(FromFriend));
3975 
3976   ASSERT_EQ(FromRecordOfFriend->getDeclContext(), cast<DeclContext>(FromTu));
3977   ASSERT_EQ(FromRecordOfFriend->getLexicalDeclContext(),
3978             cast<DeclContext>(FromX));
3979   ASSERT_FALSE(
3980       FromRecordOfFriend->getDeclContext()->containsDecl(FromRecordOfFriend));
3981   ASSERT_FALSE(FromRecordOfFriend->getLexicalDeclContext()->containsDecl(
3982       FromRecordOfFriend));
3983   ASSERT_FALSE(FromRecordOfFriend->getLookupParent()
3984                    ->lookup(FromRecordOfFriend->getDeclName())
3985                    .empty());
3986 
3987   auto *ToX = Import(FromX, Lang_CXX03);
3988   ASSERT_TRUE(ToX);
3989 
3990   Decl *ToTu = ToX->getTranslationUnitDecl();
3991   auto *ToFriend = FirstDeclMatcher<FriendDecl>().match(ToTu, friendDecl());
3992   RecordDecl *ToRecordOfFriend =
3993       const_cast<RecordDecl *>(getRecordDeclOfFriend(ToFriend));
3994 
3995   ASSERT_EQ(ToRecordOfFriend->getDeclContext(), cast<DeclContext>(ToTu));
3996   ASSERT_EQ(ToRecordOfFriend->getLexicalDeclContext(), cast<DeclContext>(ToX));
3997   EXPECT_FALSE(
3998       ToRecordOfFriend->getDeclContext()->containsDecl(ToRecordOfFriend));
3999   EXPECT_FALSE(ToRecordOfFriend->getLexicalDeclContext()->containsDecl(
4000       ToRecordOfFriend));
4001   EXPECT_FALSE(ToRecordOfFriend->getLookupParent()
4002                    ->lookup(ToRecordOfFriend->getDeclName())
4003                    .empty());
4004 }
4005 
4006 TEST_P(ImportFriendClasses, ImportOfRecursiveFriendClassTemplate) {
4007   Decl *FromTu = getTuDecl(
4008       R"(
4009       template<class A> class declToImport {
4010         template<class A1> friend class declToImport;
4011       };
4012       )",
4013       Lang_CXX03, "input.cc");
4014 
4015   auto *FromD =
4016       FirstDeclMatcher<ClassTemplateDecl>().match(FromTu, classTemplateDecl());
4017   auto *ToD = Import(FromD, Lang_CXX03);
4018 
4019   auto Pattern = classTemplateDecl(
4020       has(cxxRecordDecl(has(friendDecl(has(classTemplateDecl()))))));
4021   ASSERT_TRUE(MatchVerifier<Decl>{}.match(FromD, Pattern));
4022   EXPECT_TRUE(MatchVerifier<Decl>{}.match(ToD, Pattern));
4023 
4024   auto *Class =
4025       FirstDeclMatcher<ClassTemplateDecl>().match(ToD, classTemplateDecl());
4026   auto *Friend = FirstDeclMatcher<FriendDecl>().match(ToD, friendDecl());
4027   EXPECT_NE(Friend->getFriendDecl(), Class);
4028   EXPECT_EQ(Friend->getFriendDecl()->getPreviousDecl(), Class);
4029 }
4030 
4031 TEST_P(ImportFriendClasses, ProperPrevDeclForClassTemplateDecls) {
4032   auto Pattern = classTemplateSpecializationDecl(hasName("X"));
4033 
4034   ClassTemplateSpecializationDecl *Imported1;
4035   {
4036     Decl *FromTU = getTuDecl("template<class T> class X;"
4037                              "struct Y { friend class X<int>; };",
4038                              Lang_CXX03, "input0.cc");
4039     auto *FromD = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
4040         FromTU, Pattern);
4041 
4042     Imported1 =
4043         cast<ClassTemplateSpecializationDecl>(Import(FromD, Lang_CXX03));
4044   }
4045   ClassTemplateSpecializationDecl *Imported2;
4046   {
4047     Decl *FromTU = getTuDecl("template<class T> class X;"
4048                              "template<> class X<int>{};"
4049                              "struct Z { friend class X<int>; };",
4050                              Lang_CXX03, "input1.cc");
4051     auto *FromD = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
4052         FromTU, Pattern);
4053 
4054     Imported2 =
4055         cast<ClassTemplateSpecializationDecl>(Import(FromD, Lang_CXX03));
4056   }
4057 
4058   Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4059   EXPECT_EQ(DeclCounter<ClassTemplateSpecializationDecl>().match(ToTU, Pattern),
4060             2u);
4061   ASSERT_TRUE(Imported2->getPreviousDecl());
4062   EXPECT_EQ(Imported2->getPreviousDecl(), Imported1);
4063 }
4064 
4065 TEST_P(ImportFriendClasses, TypeForDeclShouldBeSetInTemplated) {
4066   Decl *FromTU0 = getTuDecl(
4067       R"(
4068       class X {
4069         class Y;
4070       };
4071       class X::Y {
4072         template <typename T>
4073         friend class F; // The decl context of F is the global namespace.
4074       };
4075       )",
4076       Lang_CXX03, "input0.cc");
4077   auto *Fwd = FirstDeclMatcher<ClassTemplateDecl>().match(
4078       FromTU0, classTemplateDecl(hasName("F")));
4079   auto *Imported0 = cast<ClassTemplateDecl>(Import(Fwd, Lang_CXX03));
4080   Decl *FromTU1 = getTuDecl(
4081       R"(
4082       template <typename T>
4083       class F {};
4084       )",
4085       Lang_CXX03, "input1.cc");
4086   auto *Definition = FirstDeclMatcher<ClassTemplateDecl>().match(
4087       FromTU1, classTemplateDecl(hasName("F")));
4088   auto *Imported1 = cast<ClassTemplateDecl>(Import(Definition, Lang_CXX03));
4089   EXPECT_EQ(Imported0->getTemplatedDecl()->getTypeForDecl(),
4090             Imported1->getTemplatedDecl()->getTypeForDecl());
4091 }
4092 
4093 TEST_P(ImportFriendClasses, DeclsFromFriendsShouldBeInRedeclChains) {
4094   Decl *From, *To;
4095   std::tie(From, To) =
4096       getImportedDecl("class declToImport {};", Lang_CXX03,
4097                       "class Y { friend class declToImport; };", Lang_CXX03);
4098   auto *Imported = cast<CXXRecordDecl>(To);
4099 
4100   EXPECT_TRUE(Imported->getPreviousDecl());
4101 }
4102 
4103 TEST_P(ImportFriendClasses,
4104        ImportOfClassTemplateDefinitionShouldConnectToFwdFriend) {
4105   Decl *ToTU = getToTuDecl(
4106       R"(
4107       class X {
4108         class Y;
4109       };
4110       class X::Y {
4111         template <typename T>
4112         friend class F; // The decl context of F is the global namespace.
4113       };
4114       )",
4115       Lang_CXX03);
4116   auto *ToDecl = FirstDeclMatcher<ClassTemplateDecl>().match(
4117       ToTU, classTemplateDecl(hasName("F")));
4118   Decl *FromTU = getTuDecl(
4119       R"(
4120       template <typename T>
4121       class F {};
4122       )",
4123       Lang_CXX03, "input0.cc");
4124   auto *Definition = FirstDeclMatcher<ClassTemplateDecl>().match(
4125       FromTU, classTemplateDecl(hasName("F")));
4126   auto *ImportedDef = cast<ClassTemplateDecl>(Import(Definition, Lang_CXX03));
4127   EXPECT_TRUE(ImportedDef->getPreviousDecl());
4128   EXPECT_EQ(ToDecl, ImportedDef->getPreviousDecl());
4129   EXPECT_EQ(ToDecl->getTemplatedDecl(),
4130             ImportedDef->getTemplatedDecl()->getPreviousDecl());
4131 }
4132 
4133 TEST_P(ImportFriendClasses,
4134        ImportOfClassTemplateDefinitionAndFwdFriendShouldBeLinked) {
4135   Decl *FromTU0 = getTuDecl(
4136       R"(
4137       class X {
4138         class Y;
4139       };
4140       class X::Y {
4141         template <typename T>
4142         friend class F; // The decl context of F is the global namespace.
4143       };
4144       )",
4145       Lang_CXX03, "input0.cc");
4146   auto *Fwd = FirstDeclMatcher<ClassTemplateDecl>().match(
4147       FromTU0, classTemplateDecl(hasName("F")));
4148   auto *ImportedFwd = cast<ClassTemplateDecl>(Import(Fwd, Lang_CXX03));
4149   Decl *FromTU1 = getTuDecl(
4150       R"(
4151       template <typename T>
4152       class F {};
4153       )",
4154       Lang_CXX03, "input1.cc");
4155   auto *Definition = FirstDeclMatcher<ClassTemplateDecl>().match(
4156       FromTU1, classTemplateDecl(hasName("F")));
4157   auto *ImportedDef = cast<ClassTemplateDecl>(Import(Definition, Lang_CXX03));
4158   EXPECT_TRUE(ImportedDef->getPreviousDecl());
4159   EXPECT_EQ(ImportedFwd, ImportedDef->getPreviousDecl());
4160   EXPECT_EQ(ImportedFwd->getTemplatedDecl(),
4161             ImportedDef->getTemplatedDecl()->getPreviousDecl());
4162 }
4163 
4164 TEST_P(ImportFriendClasses, ImportOfClassDefinitionAndFwdFriendShouldBeLinked) {
4165   Decl *FromTU0 = getTuDecl(
4166       R"(
4167       class X {
4168         class Y;
4169       };
4170       class X::Y {
4171         friend class F; // The decl context of F is the global namespace.
4172       };
4173       )",
4174       Lang_CXX03, "input0.cc");
4175   auto *Friend = FirstDeclMatcher<FriendDecl>().match(FromTU0, friendDecl());
4176   QualType FT = Friend->getFriendType()->getType();
4177   FT = FromTU0->getASTContext().getCanonicalType(FT);
4178   auto *Fwd = cast<TagType>(FT)->getDecl();
4179   auto *ImportedFwd = Import(Fwd, Lang_CXX03);
4180   Decl *FromTU1 = getTuDecl(
4181       R"(
4182       class F {};
4183       )",
4184       Lang_CXX03, "input1.cc");
4185   auto *Definition = FirstDeclMatcher<CXXRecordDecl>().match(
4186       FromTU1, cxxRecordDecl(hasName("F")));
4187   auto *ImportedDef = Import(Definition, Lang_CXX03);
4188   EXPECT_TRUE(ImportedDef->getPreviousDecl());
4189   EXPECT_EQ(ImportedFwd, ImportedDef->getPreviousDecl());
4190 }
4191 
4192 TEST_P(ImportFriendClasses, ImportOfRepeatedFriendType) {
4193   const char *Code =
4194       R"(
4195       class Container {
4196         friend class X;
4197         friend class X;
4198       };
4199       )";
4200   Decl *ToTu = getToTuDecl(Code, Lang_CXX03);
4201   Decl *FromTu = getTuDecl(Code, Lang_CXX03, "from.cc");
4202 
4203   auto *ToFriend1 = FirstDeclMatcher<FriendDecl>().match(ToTu, friendDecl());
4204   auto *ToFriend2 = LastDeclMatcher<FriendDecl>().match(ToTu, friendDecl());
4205   auto *FromFriend1 =
4206       FirstDeclMatcher<FriendDecl>().match(FromTu, friendDecl());
4207   auto *FromFriend2 = LastDeclMatcher<FriendDecl>().match(FromTu, friendDecl());
4208 
4209   FriendDecl *ToImportedFriend1 = Import(FromFriend1, Lang_CXX03);
4210   FriendDecl *ToImportedFriend2 = Import(FromFriend2, Lang_CXX03);
4211 
4212   EXPECT_NE(ToImportedFriend1, ToImportedFriend2);
4213   EXPECT_EQ(ToFriend1, ToImportedFriend1);
4214   EXPECT_EQ(ToFriend2, ToImportedFriend2);
4215 }
4216 
4217 TEST_P(ImportFriendClasses, ImportOfRepeatedFriendDecl) {
4218   const char *Code =
4219       R"(
4220       class Container {
4221         friend void f();
4222         friend void f();
4223       };
4224       )";
4225   Decl *ToTu = getToTuDecl(Code, Lang_CXX03);
4226   Decl *FromTu = getTuDecl(Code, Lang_CXX03, "from.cc");
4227 
4228   auto *ToFriend1 = FirstDeclMatcher<FriendDecl>().match(ToTu, friendDecl());
4229   auto *ToFriend2 = LastDeclMatcher<FriendDecl>().match(ToTu, friendDecl());
4230   auto *FromFriend1 =
4231       FirstDeclMatcher<FriendDecl>().match(FromTu, friendDecl());
4232   auto *FromFriend2 = LastDeclMatcher<FriendDecl>().match(FromTu, friendDecl());
4233 
4234   FriendDecl *ToImportedFriend1 = Import(FromFriend1, Lang_CXX03);
4235   FriendDecl *ToImportedFriend2 = Import(FromFriend2, Lang_CXX03);
4236 
4237   EXPECT_NE(ToImportedFriend1, ToImportedFriend2);
4238   EXPECT_EQ(ToFriend1, ToImportedFriend1);
4239   EXPECT_EQ(ToFriend2, ToImportedFriend2);
4240 }
4241 
4242 TEST_P(ASTImporterOptionSpecificTestBase, FriendFunInClassTemplate) {
4243   auto *Code = R"(
4244   template <class T>
4245   struct X {
4246     friend void foo(){}
4247   };
4248       )";
4249   TranslationUnitDecl *ToTU = getToTuDecl(Code, Lang_CXX03);
4250   auto *ToFoo = FirstDeclMatcher<FunctionDecl>().match(
4251       ToTU, functionDecl(hasName("foo")));
4252 
4253   TranslationUnitDecl *FromTU = getTuDecl(Code, Lang_CXX03, "input.cc");
4254   auto *FromFoo = FirstDeclMatcher<FunctionDecl>().match(
4255       FromTU, functionDecl(hasName("foo")));
4256   auto *ImportedFoo = Import(FromFoo, Lang_CXX03);
4257   EXPECT_EQ(ImportedFoo, ToFoo);
4258 }
4259 
4260 struct DeclContextTest : ASTImporterOptionSpecificTestBase {};
4261 
4262 TEST_P(DeclContextTest, removeDeclOfClassTemplateSpecialization) {
4263   Decl *TU = getTuDecl(
4264       R"(
4265       namespace NS {
4266 
4267       template <typename T>
4268       struct S {};
4269       template struct S<int>;
4270 
4271       inline namespace INS {
4272         template <typename T>
4273         struct S {};
4274         template struct S<int>;
4275       }
4276 
4277       }
4278       )", Lang_CXX11, "input0.cc");
4279   auto *NS = FirstDeclMatcher<NamespaceDecl>().match(
4280       TU, namespaceDecl());
4281   auto *Spec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
4282       TU, classTemplateSpecializationDecl());
4283   ASSERT_TRUE(NS->containsDecl(Spec));
4284 
4285   NS->removeDecl(Spec);
4286   EXPECT_FALSE(NS->containsDecl(Spec));
4287 }
4288 
4289 TEST_P(DeclContextTest,
4290        removeDeclShouldNotFailEvenIfWeHaveExternalVisibleStorage) {
4291   Decl *TU = getTuDecl("extern int A; int A;", Lang_CXX03);
4292   auto *A0 = FirstDeclMatcher<VarDecl>().match(TU, varDecl(hasName("A")));
4293   auto *A1 = LastDeclMatcher<VarDecl>().match(TU, varDecl(hasName("A")));
4294 
4295   // Investigate the list.
4296   auto *DC = A0->getDeclContext();
4297   ASSERT_TRUE(DC->containsDecl(A0));
4298   ASSERT_TRUE(DC->containsDecl(A1));
4299 
4300   // Investigate the lookup table.
4301   auto *Map = DC->getLookupPtr();
4302   ASSERT_TRUE(Map);
4303   auto I = Map->find(A0->getDeclName());
4304   ASSERT_NE(I, Map->end());
4305   StoredDeclsList &L = I->second;
4306   // The lookup table contains the most recent decl of A.
4307   ASSERT_NE(L.getAsDecl(), A0);
4308   ASSERT_EQ(L.getAsDecl(), A1);
4309 
4310   ASSERT_TRUE(L.getAsDecl());
4311   // Simulate the private function DeclContext::reconcileExternalVisibleStorage.
4312   // We do not have a list with one element.
4313   L.setHasExternalDecls();
4314   ASSERT_FALSE(L.getAsList());
4315   auto Results = L.getLookupResult();
4316   ASSERT_EQ(1u, std::distance(Results.begin(), Results.end()));
4317 
4318   // This asserts in the old implementation.
4319   DC->removeDecl(A0);
4320   EXPECT_FALSE(DC->containsDecl(A0));
4321 
4322   // Make sure we do not leave a StoredDeclsList with no entries.
4323   DC->removeDecl(A1);
4324   ASSERT_EQ(Map->find(A1->getDeclName()), Map->end());
4325 }
4326 
4327 struct ImportFunctionTemplateSpecializations
4328     : ASTImporterOptionSpecificTestBase {};
4329 
4330 TEST_P(ImportFunctionTemplateSpecializations,
4331        TUshouldNotContainFunctionTemplateImplicitInstantiation) {
4332 
4333   Decl *FromTU = getTuDecl(
4334       R"(
4335       template<class T>
4336       int f() { return 0; }
4337       void foo() { f<int>(); }
4338       )",
4339       Lang_CXX03, "input0.cc");
4340 
4341   // Check that the function template instantiation is NOT the child of the TU.
4342   auto Pattern = translationUnitDecl(
4343       unless(has(functionDecl(hasName("f"), isTemplateInstantiation()))));
4344   ASSERT_TRUE(MatchVerifier<Decl>{}.match(FromTU, Pattern));
4345 
4346   auto *Foo = FirstDeclMatcher<FunctionDecl>().match(
4347       FromTU, functionDecl(hasName("foo")));
4348   ASSERT_TRUE(Import(Foo, Lang_CXX03));
4349 
4350   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4351   EXPECT_TRUE(MatchVerifier<Decl>{}.match(ToTU, Pattern));
4352 }
4353 
4354 TEST_P(ImportFunctionTemplateSpecializations,
4355        TUshouldNotContainFunctionTemplateExplicitInstantiation) {
4356 
4357   Decl *FromTU = getTuDecl(
4358       R"(
4359       template<class T>
4360       int f() { return 0; }
4361       template int f<int>();
4362       )",
4363       Lang_CXX03, "input0.cc");
4364 
4365   // Check that the function template instantiation is NOT the child of the TU.
4366   auto Instantiation = functionDecl(hasName("f"), isTemplateInstantiation());
4367   auto Pattern = translationUnitDecl(unless(has(Instantiation)));
4368   ASSERT_TRUE(MatchVerifier<Decl>{}.match(FromTU, Pattern));
4369 
4370   ASSERT_TRUE(Import(FirstDeclMatcher<Decl>().match(FromTU, Instantiation),
4371                      Lang_CXX03));
4372 
4373   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4374   EXPECT_TRUE(MatchVerifier<Decl>{}.match(ToTU, Pattern));
4375 }
4376 
4377 TEST_P(ImportFunctionTemplateSpecializations,
4378        TUshouldContainFunctionTemplateSpecialization) {
4379 
4380   Decl *FromTU = getTuDecl(
4381       R"(
4382       template<class T>
4383       int f() { return 0; }
4384       template <> int f<int>() { return 4; }
4385       )",
4386       Lang_CXX03, "input0.cc");
4387 
4388   // Check that the function template specialization is the child of the TU.
4389   auto Specialization =
4390       functionDecl(hasName("f"), isExplicitTemplateSpecialization());
4391   auto Pattern = translationUnitDecl(has(Specialization));
4392   ASSERT_TRUE(MatchVerifier<Decl>{}.match(FromTU, Pattern));
4393 
4394   ASSERT_TRUE(Import(FirstDeclMatcher<Decl>().match(FromTU, Specialization),
4395                      Lang_CXX03));
4396 
4397   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4398   EXPECT_TRUE(MatchVerifier<Decl>{}.match(ToTU, Pattern));
4399 }
4400 
4401 TEST_P(ImportFunctionTemplateSpecializations,
4402        FunctionTemplateSpecializationRedeclChain) {
4403 
4404   Decl *FromTU = getTuDecl(
4405       R"(
4406       template<class T>
4407       int f() { return 0; }
4408       template <> int f<int>() { return 4; }
4409       )",
4410       Lang_CXX03, "input0.cc");
4411 
4412   auto Spec = functionDecl(hasName("f"), isExplicitTemplateSpecialization(),
4413                            hasParent(translationUnitDecl()));
4414   auto *FromSpecD = FirstDeclMatcher<Decl>().match(FromTU, Spec);
4415   {
4416     auto *TU = FromTU;
4417     auto *SpecD = FromSpecD;
4418     auto *TemplateD = FirstDeclMatcher<FunctionTemplateDecl>().match(
4419         TU, functionTemplateDecl());
4420     auto *FirstSpecD = *(TemplateD->spec_begin());
4421     ASSERT_EQ(SpecD, FirstSpecD);
4422     ASSERT_TRUE(SpecD->getPreviousDecl());
4423     ASSERT_FALSE(cast<FunctionDecl>(SpecD->getPreviousDecl())
4424                      ->doesThisDeclarationHaveABody());
4425   }
4426 
4427   ASSERT_TRUE(Import(FromSpecD, Lang_CXX03));
4428 
4429   {
4430     auto *TU = ToAST->getASTContext().getTranslationUnitDecl();
4431     auto *SpecD = FirstDeclMatcher<Decl>().match(TU, Spec);
4432     auto *TemplateD = FirstDeclMatcher<FunctionTemplateDecl>().match(
4433         TU, functionTemplateDecl());
4434     auto *FirstSpecD = *(TemplateD->spec_begin());
4435     EXPECT_EQ(SpecD, FirstSpecD);
4436     ASSERT_TRUE(SpecD->getPreviousDecl());
4437     EXPECT_FALSE(cast<FunctionDecl>(SpecD->getPreviousDecl())
4438                      ->doesThisDeclarationHaveABody());
4439   }
4440 }
4441 
4442 TEST_P(ImportFunctionTemplateSpecializations,
4443        MatchNumberOfFunctionTemplateSpecializations) {
4444 
4445   Decl *FromTU = getTuDecl(
4446       R"(
4447       template <typename T> constexpr int f() { return 0; }
4448       template <> constexpr int f<int>() { return 4; }
4449       void foo() {
4450         static_assert(f<char>() == 0, "");
4451         static_assert(f<int>() == 4, "");
4452       }
4453       )",
4454       Lang_CXX11, "input0.cc");
4455   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
4456       FromTU, functionDecl(hasName("foo")));
4457 
4458   Import(FromD, Lang_CXX11);
4459   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4460   EXPECT_EQ(
4461       DeclCounter<FunctionDecl>().match(FromTU, functionDecl(hasName("f"))),
4462       DeclCounter<FunctionDecl>().match(ToTU, functionDecl(hasName("f"))));
4463 }
4464 
4465 TEST_P(ASTImporterOptionSpecificTestBase,
4466     ImportShouldNotReportFalseODRErrorWhenRecordIsBeingDefined) {
4467   {
4468     Decl *FromTU = getTuDecl(
4469         R"(
4470             template <typename T>
4471             struct B;
4472             )",
4473         Lang_CXX03, "input0.cc");
4474     auto *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
4475         FromTU, classTemplateDecl(hasName("B")));
4476 
4477     Import(FromD, Lang_CXX03);
4478   }
4479 
4480   {
4481     Decl *FromTU = getTuDecl(
4482         R"(
4483             template <typename T>
4484             struct B {
4485               void f();
4486               B* b;
4487             };
4488             )",
4489         Lang_CXX03, "input1.cc");
4490     FunctionDecl *FromD = FirstDeclMatcher<FunctionDecl>().match(
4491         FromTU, functionDecl(hasName("f")));
4492     Import(FromD, Lang_CXX03);
4493     auto *FromCTD = FirstDeclMatcher<ClassTemplateDecl>().match(
4494         FromTU, classTemplateDecl(hasName("B")));
4495     auto *ToCTD = cast<ClassTemplateDecl>(Import(FromCTD, Lang_CXX03));
4496     EXPECT_TRUE(ToCTD->isThisDeclarationADefinition());
4497 
4498     // We expect no (ODR) warning during the import.
4499     auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
4500     EXPECT_EQ(0u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
4501   }
4502 }
4503 
4504 TEST_P(ASTImporterOptionSpecificTestBase,
4505        ImportingTypedefShouldImportTheCompleteType) {
4506   // We already have an incomplete underlying type in the "To" context.
4507   auto Code =
4508       R"(
4509       template <typename T>
4510       struct S {
4511         void foo();
4512       };
4513       using U = S<int>;
4514       )";
4515   Decl *ToTU = getToTuDecl(Code, Lang_CXX11);
4516   auto *ToD = FirstDeclMatcher<TypedefNameDecl>().match(ToTU,
4517       typedefNameDecl(hasName("U")));
4518   ASSERT_TRUE(ToD->getUnderlyingType()->isIncompleteType());
4519 
4520   // The "From" context has the same typedef, but the underlying type is
4521   // complete this time.
4522   Decl *FromTU = getTuDecl(std::string(Code) +
4523       R"(
4524       void foo(U* u) {
4525         u->foo();
4526       }
4527       )", Lang_CXX11);
4528   auto *FromD = FirstDeclMatcher<TypedefNameDecl>().match(FromTU,
4529       typedefNameDecl(hasName("U")));
4530   ASSERT_FALSE(FromD->getUnderlyingType()->isIncompleteType());
4531 
4532   // The imported type should be complete.
4533   auto *ImportedD = cast<TypedefNameDecl>(Import(FromD, Lang_CXX11));
4534   EXPECT_FALSE(ImportedD->getUnderlyingType()->isIncompleteType());
4535 }
4536 
4537 TEST_P(ASTImporterOptionSpecificTestBase, ImportTemplateParameterLists) {
4538   auto Code =
4539       R"(
4540       template<class T>
4541       int f() { return 0; }
4542       template <> int f<int>() { return 4; }
4543       )";
4544 
4545   Decl *FromTU = getTuDecl(Code, Lang_CXX03);
4546   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU,
4547       functionDecl(hasName("f"), isExplicitTemplateSpecialization()));
4548   ASSERT_EQ(FromD->getNumTemplateParameterLists(), 1u);
4549 
4550   auto *ToD = Import(FromD, Lang_CXX03);
4551   // The template parameter list should exist.
4552   EXPECT_EQ(ToD->getNumTemplateParameterLists(), 1u);
4553 }
4554 
4555 const internal::VariadicDynCastAllOfMatcher<Decl, VarTemplateDecl>
4556     varTemplateDecl;
4557 
4558 const internal::VariadicDynCastAllOfMatcher<
4559     Decl, VarTemplatePartialSpecializationDecl>
4560     varTemplatePartialSpecializationDecl;
4561 
4562 TEST_P(ASTImporterOptionSpecificTestBase,
4563        FunctionTemplateParameterDeclContext) {
4564   constexpr auto Code =
4565       R"(
4566       template<class T>
4567       void f() {};
4568       )";
4569 
4570   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
4571 
4572   auto *FromD = FirstDeclMatcher<FunctionTemplateDecl>().match(
4573       FromTU, functionTemplateDecl(hasName("f")));
4574 
4575   ASSERT_EQ(FromD->getTemplateParameters()->getParam(0)->getDeclContext(),
4576             FromD->getTemplatedDecl());
4577 
4578   auto *ToD = Import(FromD, Lang_CXX11);
4579   EXPECT_EQ(ToD->getTemplateParameters()->getParam(0)->getDeclContext(),
4580             ToD->getTemplatedDecl());
4581   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4582       ToD->getTemplatedDecl(), ToD->getTemplateParameters()->getParam(0)));
4583 }
4584 
4585 TEST_P(ASTImporterOptionSpecificTestBase, ClassTemplateParameterDeclContext) {
4586   constexpr auto Code =
4587       R"(
4588       template<class T1, class T2>
4589       struct S {};
4590       template<class T2>
4591       struct S<int, T2> {};
4592       )";
4593 
4594   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
4595 
4596   auto *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
4597       FromTU, classTemplateDecl(hasName("S")));
4598   auto *FromDPart =
4599       FirstDeclMatcher<ClassTemplatePartialSpecializationDecl>().match(
4600           FromTU, classTemplatePartialSpecializationDecl(hasName("S")));
4601 
4602   ASSERT_EQ(FromD->getTemplateParameters()->getParam(0)->getDeclContext(),
4603             FromD->getTemplatedDecl());
4604   ASSERT_EQ(FromDPart->getTemplateParameters()->getParam(0)->getDeclContext(),
4605             FromDPart);
4606 
4607   auto *ToD = Import(FromD, Lang_CXX11);
4608   auto *ToDPart = Import(FromDPart, Lang_CXX11);
4609 
4610   EXPECT_EQ(ToD->getTemplateParameters()->getParam(0)->getDeclContext(),
4611             ToD->getTemplatedDecl());
4612   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4613       ToD->getTemplatedDecl(), ToD->getTemplateParameters()->getParam(0)));
4614 
4615   EXPECT_EQ(ToDPart->getTemplateParameters()->getParam(0)->getDeclContext(),
4616             ToDPart);
4617   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4618       ToDPart, ToDPart->getTemplateParameters()->getParam(0)));
4619 }
4620 
4621 TEST_P(ASTImporterOptionSpecificTestBase,
4622        CXXDeductionGuideTemplateParameterDeclContext) {
4623   Decl *FromTU = getTuDecl(
4624       R"(
4625       template <typename T> struct A {
4626         A(T);
4627       };
4628       A a{(int)0};
4629       )",
4630       Lang_CXX17, "input.cc");
4631 // clang-format off
4632 /*
4633 |-ClassTemplateDecl 0x1fe5000 <input.cc:2:7, line:4:7> line:2:36 A
4634 | |-TemplateTypeParmDecl 0x1fe4eb0 <col:17, col:26> col:26 referenced typename depth 0 index 0 T
4635 | |-CXXRecordDecl 0x1fe4f70 <col:29, line:4:7> line:2:36 struct A definition
4636 
4637 |-FunctionTemplateDecl 0x1fe5860 <line:2:7, line:3:12> col:9 implicit <deduction guide for A>
4638 | |-TemplateTypeParmDecl 0x1fe4eb0 <line:2:17, col:26> col:26 referenced typename depth 0 index 0 T
4639 | |-CXXDeductionGuideDecl 0x1fe57a8 <line:3:9, col:12> col:9 implicit <deduction guide for A> 'auto (T) -> A<T>'
4640 | | `-ParmVarDecl 0x1fe56b0 <col:11> col:12 'T'
4641 | `-CXXDeductionGuideDecl 0x20515d8 <col:9, col:12> col:9 implicit used <deduction guide for A> 'auto (int) -> A<int>'
4642 |   |-TemplateArgument type 'int'
4643 |   | `-BuiltinType 0x20587e0 'int'
4644 |   `-ParmVarDecl 0x2051388 <col:11> col:12 'int':'int'
4645 `-FunctionTemplateDecl 0x1fe5a78 <line:2:7, col:36> col:36 implicit <deduction guide for A>
4646   |-TemplateTypeParmDecl 0x1fe4eb0 <col:17, col:26> col:26 referenced typename depth 0 index 0 T
4647   `-CXXDeductionGuideDecl 0x1fe59c0 <col:36> col:36 implicit <deduction guide for A> 'auto (A<T>) -> A<T>'
4648     `-ParmVarDecl 0x1fe5958 <col:36> col:36 'A<T>'
4649 */
4650 // clang-format on
4651   auto *FromD1 = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
4652       FromTU, cxxDeductionGuideDecl());
4653   auto *FromD2 = LastDeclMatcher<CXXDeductionGuideDecl>().match(
4654       FromTU, cxxDeductionGuideDecl());
4655 
4656   NamedDecl *P1 =
4657       FromD1->getDescribedFunctionTemplate()->getTemplateParameters()->getParam(
4658           0);
4659   NamedDecl *P2 =
4660       FromD2->getDescribedFunctionTemplate()->getTemplateParameters()->getParam(
4661           0);
4662   DeclContext *DC = P1->getDeclContext();
4663 
4664   ASSERT_EQ(P1, P2);
4665   ASSERT_TRUE(DC == FromD1 || DC == FromD2);
4666 
4667   auto *ToD1 = Import(FromD1, Lang_CXX17);
4668   auto *ToD2 = Import(FromD2, Lang_CXX17);
4669   ASSERT_TRUE(ToD1 && ToD2);
4670 
4671   P1 = ToD1->getDescribedFunctionTemplate()->getTemplateParameters()->getParam(
4672       0);
4673   P2 = ToD2->getDescribedFunctionTemplate()->getTemplateParameters()->getParam(
4674       0);
4675   DC = P1->getDeclContext();
4676 
4677   EXPECT_EQ(P1, P2);
4678   EXPECT_TRUE(DC == ToD1 || DC == ToD2);
4679 
4680   ASTImporterLookupTable *Tbl = SharedStatePtr->getLookupTable();
4681   if (Tbl->contains(ToD1, P1)) {
4682     EXPECT_FALSE(Tbl->contains(ToD2, P1));
4683   } else {
4684     EXPECT_TRUE(Tbl->contains(ToD2, P1));
4685   }
4686 }
4687 
4688 TEST_P(ASTImporterOptionSpecificTestBase, VarTemplateParameterDeclContext) {
4689   constexpr auto Code =
4690       R"(
4691       template<class T1, class T2>
4692       int X1;
4693       template<class T2>
4694       int X1<int, T2>;
4695 
4696       namespace Ns {
4697         template<class T1, class T2>
4698         int X2;
4699         template<class T2>
4700         int X2<int, T2>;
4701       }
4702       )";
4703 
4704   Decl *FromTU = getTuDecl(Code, Lang_CXX14);
4705 
4706   auto *FromD1 = FirstDeclMatcher<VarTemplateDecl>().match(
4707       FromTU, varTemplateDecl(hasName("X1")));
4708   auto *FromD1Part =
4709       FirstDeclMatcher<VarTemplatePartialSpecializationDecl>().match(
4710           FromTU, varTemplatePartialSpecializationDecl(hasName("X1")));
4711   auto *FromD2 = FirstDeclMatcher<VarTemplateDecl>().match(
4712       FromTU, varTemplateDecl(hasName("X2")));
4713   auto *FromD2Part =
4714       FirstDeclMatcher<VarTemplatePartialSpecializationDecl>().match(
4715           FromTU, varTemplatePartialSpecializationDecl(hasName("X2")));
4716 
4717   ASSERT_EQ(FromD1->getTemplateParameters()->getParam(0)->getDeclContext(),
4718             FromD1->getDeclContext());
4719   ASSERT_EQ(FromD2->getTemplateParameters()->getParam(0)->getDeclContext(),
4720             FromD2->getDeclContext());
4721 
4722   ASSERT_EQ(FromD1Part->getTemplateParameters()->getParam(0)->getDeclContext(),
4723             FromD1Part->getDeclContext());
4724   // FIXME: VarTemplatePartialSpecializationDecl does not update ("adopt")
4725   // template parameter decl context
4726   // ASSERT_EQ(FromD2Part->getTemplateParameters()->getParam(0)->getDeclContext(),
4727   // FromD2Part->getDeclContext());
4728 
4729   auto *ToD1 = Import(FromD1, Lang_CXX14);
4730   auto *ToD2 = Import(FromD2, Lang_CXX14);
4731 
4732   auto *ToD1Part = Import(FromD1Part, Lang_CXX14);
4733   auto *ToD2Part = Import(FromD2Part, Lang_CXX14);
4734 
4735   EXPECT_EQ(ToD1->getTemplateParameters()->getParam(0)->getDeclContext(),
4736             ToD1->getDeclContext());
4737   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4738       ToD1->getDeclContext(), ToD1->getTemplateParameters()->getParam(0)));
4739   EXPECT_EQ(ToD2->getTemplateParameters()->getParam(0)->getDeclContext(),
4740             ToD2->getDeclContext());
4741   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4742       ToD2->getDeclContext(), ToD2->getTemplateParameters()->getParam(0)));
4743 
4744   EXPECT_EQ(ToD1Part->getTemplateParameters()->getParam(0)->getDeclContext(),
4745             ToD1Part->getDeclContext());
4746   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4747       ToD1Part->getDeclContext(),
4748       ToD1Part->getTemplateParameters()->getParam(0)));
4749   // EXPECT_EQ(ToD2Part->getTemplateParameters()->getParam(0)->getDeclContext(),
4750   // ToD2Part->getDeclContext());
4751   // EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4752   //     ToD2Part->getDeclContext(),
4753   //     ToD2Part->getTemplateParameters()->getParam(0)));
4754   (void)ToD2Part;
4755 }
4756 
4757 TEST_P(ASTImporterOptionSpecificTestBase,
4758        TypeAliasTemplateParameterDeclContext) {
4759   constexpr auto Code =
4760       R"(
4761       template<class T1, class T2>
4762       struct S {};
4763       template<class T> using S1 = S<T, int>;
4764       namespace Ns {
4765         template<class T> using S2 = S<T, int>;
4766       }
4767       )";
4768 
4769   Decl *FromTU = getTuDecl(Code, Lang_CXX11);
4770 
4771   auto *FromD1 = FirstDeclMatcher<TypeAliasTemplateDecl>().match(
4772       FromTU, typeAliasTemplateDecl(hasName("S1")));
4773   auto *FromD2 = FirstDeclMatcher<TypeAliasTemplateDecl>().match(
4774       FromTU, typeAliasTemplateDecl(hasName("S2")));
4775 
4776   ASSERT_EQ(FromD1->getTemplateParameters()->getParam(0)->getDeclContext(),
4777             FromD1->getDeclContext());
4778   ASSERT_EQ(FromD2->getTemplateParameters()->getParam(0)->getDeclContext(),
4779             FromD2->getDeclContext());
4780 
4781   auto *ToD1 = Import(FromD1, Lang_CXX11);
4782   auto *ToD2 = Import(FromD2, Lang_CXX11);
4783 
4784   EXPECT_EQ(ToD1->getTemplateParameters()->getParam(0)->getDeclContext(),
4785             ToD1->getDeclContext());
4786   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4787       ToD1->getDeclContext(), ToD1->getTemplateParameters()->getParam(0)));
4788   EXPECT_EQ(ToD2->getTemplateParameters()->getParam(0)->getDeclContext(),
4789             ToD2->getDeclContext());
4790   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
4791       ToD2->getDeclContext(), ToD2->getTemplateParameters()->getParam(0)));
4792 }
4793 
4794 const AstTypeMatcher<SubstTemplateTypeParmPackType>
4795     substTemplateTypeParmPackType;
4796 
4797 TEST_P(ASTImporterOptionSpecificTestBase, ImportSubstTemplateTypeParmPackType) {
4798   constexpr auto Code = R"(
4799     template<typename ...T> struct D {
4800       template<typename... U> using B = int(int (*...p)(T, U));
4801       template<typename U1, typename U2> D(B<U1, U2>*);
4802     };
4803     int f(int(int, int), int(int, int));
4804 
4805     using asd = D<float, double, float>::B<int, long, int>;
4806     )";
4807   Decl *FromTU = getTuDecl(Code, Lang_CXX11, "input.cpp");
4808   auto *FromClass = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
4809       FromTU, classTemplateSpecializationDecl());
4810 
4811   {
4812     ASTContext &FromCtx = FromTU->getASTContext();
4813     const auto *FromSubstPack = selectFirst<SubstTemplateTypeParmPackType>(
4814         "pack", match(substTemplateTypeParmPackType().bind("pack"), FromCtx));
4815 
4816     ASSERT_TRUE(FromSubstPack);
4817     ASSERT_EQ(FromSubstPack->getIdentifier()->getName(), "T");
4818     ArrayRef<TemplateArgument> FromArgPack =
4819         FromSubstPack->getArgumentPack().pack_elements();
4820     ASSERT_EQ(FromArgPack.size(), 3u);
4821     ASSERT_EQ(FromArgPack[0].getAsType(), FromCtx.FloatTy);
4822     ASSERT_EQ(FromArgPack[1].getAsType(), FromCtx.DoubleTy);
4823     ASSERT_EQ(FromArgPack[2].getAsType(), FromCtx.FloatTy);
4824   }
4825   {
4826     // Let's do the import.
4827     ClassTemplateSpecializationDecl *ToClass = Import(FromClass, Lang_CXX11);
4828     ASTContext &ToCtx = ToClass->getASTContext();
4829 
4830     const auto *ToSubstPack = selectFirst<SubstTemplateTypeParmPackType>(
4831         "pack", match(substTemplateTypeParmPackType().bind("pack"), ToCtx));
4832 
4833     // Check if it meets the requirements.
4834     ASSERT_TRUE(ToSubstPack);
4835     ASSERT_EQ(ToSubstPack->getIdentifier()->getName(), "T");
4836     ArrayRef<TemplateArgument> ToArgPack =
4837         ToSubstPack->getArgumentPack().pack_elements();
4838     ASSERT_EQ(ToArgPack.size(), 3u);
4839     ASSERT_EQ(ToArgPack[0].getAsType(), ToCtx.FloatTy);
4840     ASSERT_EQ(ToArgPack[1].getAsType(), ToCtx.DoubleTy);
4841     ASSERT_EQ(ToArgPack[2].getAsType(), ToCtx.FloatTy);
4842   }
4843 }
4844 
4845 struct ASTImporterLookupTableTest : ASTImporterOptionSpecificTestBase {};
4846 
4847 TEST_P(ASTImporterLookupTableTest, OneDecl) {
4848   auto *ToTU = getToTuDecl("int a;", Lang_CXX03);
4849   auto *D = FirstDeclMatcher<VarDecl>().match(ToTU, varDecl(hasName("a")));
4850   ASTImporterLookupTable LT(*ToTU);
4851   auto Res = LT.lookup(ToTU, D->getDeclName());
4852   ASSERT_EQ(Res.size(), 1u);
4853   EXPECT_EQ(*Res.begin(), D);
4854 }
4855 
4856 static Decl *findInDeclListOfDC(DeclContext *DC, DeclarationName Name) {
4857   for (Decl *D : DC->decls()) {
4858     if (auto *ND = dyn_cast<NamedDecl>(D))
4859       if (ND->getDeclName() == Name)
4860         return ND;
4861   }
4862   return nullptr;
4863 }
4864 
4865 TEST_P(ASTImporterLookupTableTest,
4866     FriendWhichIsnotFoundByNormalLookupShouldBeFoundByImporterSpecificLookup) {
4867   auto *Code = R"(
4868   template <class T>
4869   struct X {
4870     friend void foo(){}
4871   };
4872       )";
4873   TranslationUnitDecl *ToTU = getToTuDecl(Code, Lang_CXX03);
4874   auto *X = FirstDeclMatcher<ClassTemplateDecl>().match(
4875       ToTU, classTemplateDecl(hasName("X")));
4876   auto *Foo = FirstDeclMatcher<FunctionDecl>().match(
4877       ToTU, functionDecl(hasName("foo")));
4878   DeclContext *FooDC = Foo->getDeclContext();
4879   DeclContext *FooLexicalDC = Foo->getLexicalDeclContext();
4880   ASSERT_EQ(cast<Decl>(FooLexicalDC), X->getTemplatedDecl());
4881   ASSERT_EQ(cast<Decl>(FooDC), ToTU);
4882   DeclarationName FooName = Foo->getDeclName();
4883 
4884   // Cannot find in the LookupTable of its DC (TUDecl)
4885   SmallVector<NamedDecl *, 2> FoundDecls;
4886   FooDC->getRedeclContext()->localUncachedLookup(FooName, FoundDecls);
4887   EXPECT_EQ(FoundDecls.size(), 0u);
4888 
4889   // Cannot find in the LookupTable of its LexicalDC (X)
4890   FooLexicalDC->getRedeclContext()->localUncachedLookup(FooName, FoundDecls);
4891   EXPECT_EQ(FoundDecls.size(), 0u);
4892 
4893   // Can't find in the list of Decls of the DC.
4894   EXPECT_EQ(findInDeclListOfDC(FooDC, FooName), nullptr);
4895 
4896   // Can't find in the list of Decls of the LexicalDC
4897   EXPECT_EQ(findInDeclListOfDC(FooLexicalDC, FooName), nullptr);
4898 
4899   // ASTImporter specific lookup finds it.
4900   ASTImporterLookupTable LT(*ToTU);
4901   auto Res = LT.lookup(FooDC, Foo->getDeclName());
4902   ASSERT_EQ(Res.size(), 1u);
4903   EXPECT_EQ(*Res.begin(), Foo);
4904 }
4905 
4906 TEST_P(ASTImporterLookupTableTest,
4907        FwdDeclStructShouldBeFoundByImporterSpecificLookup) {
4908   TranslationUnitDecl *ToTU =
4909       getToTuDecl("struct A { struct Foo *p; };", Lang_C99);
4910   auto *Foo =
4911       FirstDeclMatcher<RecordDecl>().match(ToTU, recordDecl(hasName("Foo")));
4912   auto *A =
4913       FirstDeclMatcher<RecordDecl>().match(ToTU, recordDecl(hasName("A")));
4914   DeclContext *FooDC = Foo->getDeclContext();
4915   DeclContext *FooLexicalDC = Foo->getLexicalDeclContext();
4916   ASSERT_EQ(cast<Decl>(FooLexicalDC), A);
4917   ASSERT_EQ(cast<Decl>(FooDC), ToTU);
4918   DeclarationName FooName = Foo->getDeclName();
4919 
4920   // Cannot find in the LookupTable of its DC (TUDecl).
4921   SmallVector<NamedDecl *, 2> FoundDecls;
4922   FooDC->getRedeclContext()->localUncachedLookup(FooName, FoundDecls);
4923   EXPECT_EQ(FoundDecls.size(), 0u);
4924 
4925   // Cannot find in the LookupTable of its LexicalDC (A).
4926   FooLexicalDC->getRedeclContext()->localUncachedLookup(FooName, FoundDecls);
4927   EXPECT_EQ(FoundDecls.size(), 0u);
4928 
4929   // Can't find in the list of Decls of the DC.
4930   EXPECT_EQ(findInDeclListOfDC(FooDC, FooName), nullptr);
4931 
4932   // Can find in the list of Decls of the LexicalDC.
4933   EXPECT_EQ(findInDeclListOfDC(FooLexicalDC, FooName), Foo);
4934 
4935   // ASTImporter specific lookup finds it.
4936   ASTImporterLookupTable LT(*ToTU);
4937   auto Res = LT.lookup(FooDC, Foo->getDeclName());
4938   ASSERT_EQ(Res.size(), 1u);
4939   EXPECT_EQ(*Res.begin(), Foo);
4940 }
4941 
4942 TEST_P(ASTImporterLookupTableTest, LookupFindsNamesInDifferentDC) {
4943   TranslationUnitDecl *ToTU =
4944       getToTuDecl("int V; struct A { int V; }; struct B { int V; };", Lang_C99);
4945   DeclarationName VName = FirstDeclMatcher<VarDecl>()
4946                               .match(ToTU, varDecl(hasName("V")))
4947                               ->getDeclName();
4948   auto *A =
4949       FirstDeclMatcher<RecordDecl>().match(ToTU, recordDecl(hasName("A")));
4950   auto *B =
4951       FirstDeclMatcher<RecordDecl>().match(ToTU, recordDecl(hasName("B")));
4952 
4953   ASTImporterLookupTable LT(*ToTU);
4954 
4955   auto Res = LT.lookup(cast<DeclContext>(A), VName);
4956   ASSERT_EQ(Res.size(), 1u);
4957   EXPECT_EQ(*Res.begin(), FirstDeclMatcher<FieldDecl>().match(
4958                         ToTU, fieldDecl(hasName("V"),
4959                                         hasParent(recordDecl(hasName("A"))))));
4960   Res = LT.lookup(cast<DeclContext>(B), VName);
4961   ASSERT_EQ(Res.size(), 1u);
4962   EXPECT_EQ(*Res.begin(), FirstDeclMatcher<FieldDecl>().match(
4963                         ToTU, fieldDecl(hasName("V"),
4964                                         hasParent(recordDecl(hasName("B"))))));
4965   Res = LT.lookup(ToTU, VName);
4966   ASSERT_EQ(Res.size(), 1u);
4967   EXPECT_EQ(*Res.begin(), FirstDeclMatcher<VarDecl>().match(
4968                         ToTU, varDecl(hasName("V"),
4969                                         hasParent(translationUnitDecl()))));
4970 }
4971 
4972 TEST_P(ASTImporterLookupTableTest, LookupFindsOverloadedNames) {
4973   TranslationUnitDecl *ToTU = getToTuDecl(
4974       R"(
4975       void foo();
4976       void foo(int);
4977       void foo(int, int);
4978       )",
4979       Lang_CXX03);
4980 
4981   ASTImporterLookupTable LT(*ToTU);
4982   auto *F0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, functionDecl());
4983   auto *F2 = LastDeclMatcher<FunctionDecl>().match(ToTU, functionDecl());
4984   DeclarationName Name = F0->getDeclName();
4985   auto Res = LT.lookup(ToTU, Name);
4986   EXPECT_EQ(Res.size(), 3u);
4987   EXPECT_EQ(Res.count(F0), 1u);
4988   EXPECT_EQ(Res.count(F2), 1u);
4989 }
4990 
4991 TEST_P(ASTImporterLookupTableTest,
4992        DifferentOperatorsShouldHaveDifferentResultSet) {
4993   TranslationUnitDecl *ToTU = getToTuDecl(
4994       R"(
4995       struct X{};
4996       void operator+(X, X);
4997       void operator-(X, X);
4998       )",
4999       Lang_CXX03);
5000 
5001   ASTImporterLookupTable LT(*ToTU);
5002   auto *FPlus = FirstDeclMatcher<FunctionDecl>().match(
5003       ToTU, functionDecl(hasOverloadedOperatorName("+")));
5004   auto *FMinus = FirstDeclMatcher<FunctionDecl>().match(
5005       ToTU, functionDecl(hasOverloadedOperatorName("-")));
5006   DeclarationName NamePlus = FPlus->getDeclName();
5007   auto ResPlus = LT.lookup(ToTU, NamePlus);
5008   EXPECT_EQ(ResPlus.size(), 1u);
5009   EXPECT_EQ(ResPlus.count(FPlus), 1u);
5010   EXPECT_EQ(ResPlus.count(FMinus), 0u);
5011   DeclarationName NameMinus = FMinus->getDeclName();
5012   auto ResMinus = LT.lookup(ToTU, NameMinus);
5013   EXPECT_EQ(ResMinus.size(), 1u);
5014   EXPECT_EQ(ResMinus.count(FMinus), 1u);
5015   EXPECT_EQ(ResMinus.count(FPlus), 0u);
5016   EXPECT_NE(*ResMinus.begin(), *ResPlus.begin());
5017 }
5018 
5019 TEST_P(ASTImporterLookupTableTest, LookupDeclNamesFromDifferentTUs) {
5020   TranslationUnitDecl *ToTU = getToTuDecl(
5021       R"(
5022       struct X {};
5023       void operator+(X, X);
5024       )",
5025       Lang_CXX03);
5026   auto *ToPlus = FirstDeclMatcher<FunctionDecl>().match(
5027       ToTU, functionDecl(hasOverloadedOperatorName("+")));
5028 
5029   Decl *FromTU = getTuDecl(
5030       R"(
5031       struct X {};
5032       void operator+(X, X);
5033       )",
5034       Lang_CXX03);
5035   auto *FromPlus = FirstDeclMatcher<FunctionDecl>().match(
5036       FromTU, functionDecl(hasOverloadedOperatorName("+")));
5037 
5038   // FromPlus have a different TU, thus its DeclarationName is different too.
5039   ASSERT_NE(ToPlus->getDeclName(), FromPlus->getDeclName());
5040 
5041   ASTImporterLookupTable LT(*ToTU);
5042   auto Res = LT.lookup(ToTU, ToPlus->getDeclName());
5043   ASSERT_EQ(Res.size(), 1u);
5044   EXPECT_EQ(*Res.begin(), ToPlus);
5045 
5046   // FromPlus have a different TU, thus its DeclarationName is different too.
5047   Res = LT.lookup(ToTU, FromPlus->getDeclName());
5048   ASSERT_EQ(Res.size(), 0u);
5049 }
5050 
5051 TEST_P(ASTImporterLookupTableTest,
5052        LookupFindsFwdFriendClassDeclWithElaboratedType) {
5053   TranslationUnitDecl *ToTU = getToTuDecl(
5054       R"(
5055       class Y { friend class F; };
5056       )",
5057       Lang_CXX03);
5058 
5059   // In this case, the CXXRecordDecl is hidden, the FriendDecl is not a parent.
5060   // So we must dig up the underlying CXXRecordDecl.
5061   ASTImporterLookupTable LT(*ToTU);
5062   auto *FriendD = FirstDeclMatcher<FriendDecl>().match(ToTU, friendDecl());
5063   const RecordDecl *RD = getRecordDeclOfFriend(FriendD);
5064   auto *Y = FirstDeclMatcher<CXXRecordDecl>().match(
5065       ToTU, cxxRecordDecl(hasName("Y")));
5066 
5067   DeclarationName Name = RD->getDeclName();
5068   auto Res = LT.lookup(ToTU, Name);
5069   EXPECT_EQ(Res.size(), 1u);
5070   EXPECT_EQ(*Res.begin(), RD);
5071 
5072   Res = LT.lookup(Y, Name);
5073   EXPECT_EQ(Res.size(), 0u);
5074 }
5075 
5076 TEST_P(ASTImporterLookupTableTest,
5077        LookupFindsFwdFriendClassDeclWithUnelaboratedType) {
5078   TranslationUnitDecl *ToTU = getToTuDecl(
5079       R"(
5080       class F;
5081       class Y { friend F; };
5082       )",
5083       Lang_CXX11);
5084 
5085   // In this case, the CXXRecordDecl is hidden, the FriendDecl is not a parent.
5086   // So we must dig up the underlying CXXRecordDecl.
5087   ASTImporterLookupTable LT(*ToTU);
5088   auto *FriendD = FirstDeclMatcher<FriendDecl>().match(ToTU, friendDecl());
5089   const RecordDecl *RD = getRecordDeclOfFriend(FriendD);
5090   auto *Y = FirstDeclMatcher<CXXRecordDecl>().match(ToTU, cxxRecordDecl(hasName("Y")));
5091 
5092   DeclarationName Name = RD->getDeclName();
5093   auto Res = LT.lookup(ToTU, Name);
5094   EXPECT_EQ(Res.size(), 1u);
5095   EXPECT_EQ(*Res.begin(), RD);
5096 
5097   Res = LT.lookup(Y, Name);
5098   EXPECT_EQ(Res.size(), 0u);
5099 }
5100 
5101 TEST_P(ASTImporterLookupTableTest,
5102        LookupFindsFriendClassDeclWithTypeAliasDoesNotAssert) {
5103   TranslationUnitDecl *ToTU = getToTuDecl(
5104       R"(
5105       class F;
5106       using alias_of_f = F;
5107       class Y { friend alias_of_f; };
5108       )",
5109       Lang_CXX11);
5110 
5111   // ASTImporterLookupTable constructor handles using declarations correctly,
5112   // no assert is expected.
5113   ASTImporterLookupTable LT(*ToTU);
5114 
5115   auto *Alias = FirstDeclMatcher<TypeAliasDecl>().match(
5116       ToTU, typeAliasDecl(hasName("alias_of_f")));
5117   DeclarationName Name = Alias->getDeclName();
5118   auto Res = LT.lookup(ToTU, Name);
5119   EXPECT_EQ(Res.count(Alias), 1u);
5120 }
5121 
5122 TEST_P(ASTImporterLookupTableTest, LookupFindsFwdFriendClassTemplateDecl) {
5123   TranslationUnitDecl *ToTU = getToTuDecl(
5124       R"(
5125       class Y { template <class T> friend class F; };
5126       )",
5127       Lang_CXX03);
5128 
5129   ASTImporterLookupTable LT(*ToTU);
5130   auto *F = FirstDeclMatcher<ClassTemplateDecl>().match(
5131       ToTU, classTemplateDecl(hasName("F")));
5132   DeclarationName Name = F->getDeclName();
5133   auto Res = LT.lookup(ToTU, Name);
5134   EXPECT_EQ(Res.size(), 2u);
5135   EXPECT_EQ(Res.count(F), 1u);
5136   EXPECT_EQ(Res.count(F->getTemplatedDecl()), 1u);
5137 }
5138 
5139 TEST_P(ASTImporterLookupTableTest, DependentFriendClass) {
5140   TranslationUnitDecl *ToTU = getToTuDecl(
5141       R"(
5142       template <typename T>
5143       class F;
5144 
5145       template <typename T>
5146       class Y {
5147         friend class F<T>;
5148       };
5149       )",
5150       Lang_CXX03);
5151 
5152   ASTImporterLookupTable LT(*ToTU);
5153   auto *F = FirstDeclMatcher<ClassTemplateDecl>().match(
5154       ToTU, classTemplateDecl(hasName("F")));
5155   DeclarationName Name = F->getDeclName();
5156   auto Res = LT.lookup(ToTU, Name);
5157   EXPECT_EQ(Res.size(), 2u);
5158   EXPECT_EQ(Res.count(F), 1u);
5159   EXPECT_EQ(Res.count(F->getTemplatedDecl()), 1u);
5160 }
5161 
5162 TEST_P(ASTImporterLookupTableTest, FriendClassTemplateSpecialization) {
5163   TranslationUnitDecl *ToTU = getToTuDecl(
5164       R"(
5165       template <typename T>
5166       class F;
5167 
5168       class Y {
5169         friend class F<int>;
5170       };
5171       )",
5172       Lang_CXX03);
5173 
5174   ASTImporterLookupTable LT(*ToTU);
5175   auto *F = FirstDeclMatcher<ClassTemplateDecl>().match(
5176       ToTU, classTemplateDecl(hasName("F")));
5177   DeclarationName Name = F->getDeclName();
5178   auto Res = LT.lookup(ToTU, Name);
5179   ASSERT_EQ(Res.size(), 3u);
5180   EXPECT_EQ(Res.count(F), 1u);
5181   EXPECT_EQ(Res.count(F->getTemplatedDecl()), 1u);
5182   EXPECT_EQ(Res.count(*F->spec_begin()), 1u);
5183 }
5184 
5185 TEST_P(ASTImporterLookupTableTest, LookupFindsFwdFriendFunctionDecl) {
5186   TranslationUnitDecl *ToTU = getToTuDecl(
5187       R"(
5188       class Y { friend void F(); };
5189       )",
5190       Lang_CXX03);
5191 
5192   ASTImporterLookupTable LT(*ToTU);
5193   auto *F =
5194       FirstDeclMatcher<FunctionDecl>().match(ToTU, functionDecl(hasName("F")));
5195   DeclarationName Name = F->getDeclName();
5196   auto Res = LT.lookup(ToTU, Name);
5197   EXPECT_EQ(Res.size(), 1u);
5198   EXPECT_EQ(*Res.begin(), F);
5199 }
5200 
5201 TEST_P(ASTImporterLookupTableTest,
5202        LookupFindsDeclsInClassTemplateSpecialization) {
5203   TranslationUnitDecl *ToTU = getToTuDecl(
5204       R"(
5205       template <typename T>
5206       struct X {
5207         int F;
5208       };
5209       void foo() {
5210         X<char> xc;
5211       }
5212       )",
5213       Lang_CXX03);
5214 
5215   ASTImporterLookupTable LT(*ToTU);
5216 
5217   auto *Template = FirstDeclMatcher<ClassTemplateDecl>().match(
5218       ToTU, classTemplateDecl(hasName("X")));
5219   auto *FieldInTemplate = FirstDeclMatcher<FieldDecl>().match(
5220       ToTU,
5221       fieldDecl(hasParent(cxxRecordDecl(hasParent(classTemplateDecl())))));
5222 
5223   auto *Spec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
5224       ToTU, classTemplateSpecializationDecl(hasName("X")));
5225   FieldDecl *FieldInSpec = *Spec->field_begin();
5226   ASSERT_TRUE(FieldInSpec);
5227 
5228   DeclarationName Name = FieldInSpec->getDeclName();
5229   auto TemplateDC = cast<DeclContext>(Template->getTemplatedDecl());
5230 
5231   SmallVector<NamedDecl *, 2> FoundDecls;
5232   TemplateDC->getRedeclContext()->localUncachedLookup(Name, FoundDecls);
5233   EXPECT_EQ(FoundDecls.size(), 1u);
5234   EXPECT_EQ(FoundDecls[0], FieldInTemplate);
5235 
5236   auto Res = LT.lookup(TemplateDC, Name);
5237   ASSERT_EQ(Res.size(), 1u);
5238   EXPECT_EQ(*Res.begin(), FieldInTemplate);
5239 
5240   cast<DeclContext>(Spec)->getRedeclContext()->localUncachedLookup(Name,
5241                                                                    FoundDecls);
5242   EXPECT_EQ(FoundDecls.size(), 1u);
5243   EXPECT_EQ(FoundDecls[0], FieldInSpec);
5244 
5245   Res = LT.lookup(cast<DeclContext>(Spec), Name);
5246   ASSERT_EQ(Res.size(), 1u);
5247   EXPECT_EQ(*Res.begin(), FieldInSpec);
5248 }
5249 
5250 TEST_P(ASTImporterLookupTableTest, LookupFindsFwdFriendFunctionTemplateDecl) {
5251   TranslationUnitDecl *ToTU = getToTuDecl(
5252       R"(
5253       class Y { template <class T> friend void F(); };
5254       )",
5255       Lang_CXX03);
5256 
5257   ASTImporterLookupTable LT(*ToTU);
5258   auto *F = FirstDeclMatcher<FunctionTemplateDecl>().match(
5259       ToTU, functionTemplateDecl(hasName("F")));
5260   DeclarationName Name = F->getDeclName();
5261   auto Res = LT.lookup(ToTU, Name);
5262   EXPECT_EQ(Res.size(), 2u);
5263   EXPECT_EQ(Res.count(F), 1u);
5264   EXPECT_EQ(Res.count(F->getTemplatedDecl()), 1u);
5265 }
5266 
5267 TEST_P(ASTImporterLookupTableTest, MultipleBefriendingClasses) {
5268   TranslationUnitDecl *ToTU = getToTuDecl(
5269       R"(
5270       struct X;
5271       struct A {
5272         friend struct X;
5273       };
5274       struct B {
5275         friend struct X;
5276       };
5277       )",
5278       Lang_CXX03);
5279 
5280   ASTImporterLookupTable LT(*ToTU);
5281   auto *X = FirstDeclMatcher<CXXRecordDecl>().match(
5282       ToTU, cxxRecordDecl(hasName("X")));
5283   auto *FriendD0 = FirstDeclMatcher<FriendDecl>().match(ToTU, friendDecl());
5284   auto *FriendD1 = LastDeclMatcher<FriendDecl>().match(ToTU, friendDecl());
5285   const RecordDecl *RD0 = getRecordDeclOfFriend(FriendD0);
5286   const RecordDecl *RD1 = getRecordDeclOfFriend(FriendD1);
5287   ASSERT_EQ(RD0, RD1);
5288   ASSERT_EQ(RD1, X);
5289 
5290   DeclarationName Name = X->getDeclName();
5291   auto Res = LT.lookup(ToTU, Name);
5292   EXPECT_EQ(Res.size(), 1u);
5293   EXPECT_EQ(*Res.begin(), X);
5294 }
5295 
5296 TEST_P(ASTImporterLookupTableTest, EnumConstantDecl) {
5297   TranslationUnitDecl *ToTU = getToTuDecl(
5298       R"(
5299       enum E {
5300         A,
5301         B
5302       };
5303       )",
5304       Lang_C99);
5305 
5306   ASTImporterLookupTable LT(*ToTU);
5307   auto *E = FirstDeclMatcher<EnumDecl>().match(ToTU, enumDecl(hasName("E")));
5308   auto *A = FirstDeclMatcher<EnumConstantDecl>().match(
5309       ToTU, enumConstantDecl(hasName("A")));
5310 
5311   DeclarationName Name = A->getDeclName();
5312   // Redecl context is the TU.
5313   ASSERT_EQ(E->getRedeclContext(), ToTU);
5314 
5315   SmallVector<NamedDecl *, 2> FoundDecls;
5316   // Normal lookup finds in the DC.
5317   E->localUncachedLookup(Name, FoundDecls);
5318   EXPECT_EQ(FoundDecls.size(), 1u);
5319 
5320   // Normal lookup finds in the Redecl context.
5321   ToTU->localUncachedLookup(Name, FoundDecls);
5322   EXPECT_EQ(FoundDecls.size(), 1u);
5323 
5324   // Import specific lookup finds in the DC.
5325   auto Res = LT.lookup(E, Name);
5326   ASSERT_EQ(Res.size(), 1u);
5327   EXPECT_EQ(*Res.begin(), A);
5328 
5329   // Import specific lookup finds in the Redecl context.
5330   Res = LT.lookup(ToTU, Name);
5331   ASSERT_EQ(Res.size(), 1u);
5332   EXPECT_EQ(*Res.begin(), A);
5333 }
5334 
5335 TEST_P(ASTImporterLookupTableTest, LookupSearchesInTheWholeRedeclChain) {
5336   TranslationUnitDecl *ToTU = getToTuDecl(
5337       R"(
5338       namespace N {
5339         int A;
5340       }
5341       namespace N {
5342       }
5343       )",
5344       Lang_CXX03);
5345   auto *N1 =
5346       LastDeclMatcher<NamespaceDecl>().match(ToTU, namespaceDecl(hasName("N")));
5347   auto *A = FirstDeclMatcher<VarDecl>().match(ToTU, varDecl(hasName("A")));
5348   DeclarationName Name = A->getDeclName();
5349 
5350   ASTImporterLookupTable LT(*ToTU);
5351   auto Res = LT.lookup(N1, Name);
5352   ASSERT_EQ(Res.size(), 1u);
5353   EXPECT_EQ(*Res.begin(), A);
5354 }
5355 
5356 TEST_P(ASTImporterOptionSpecificTestBase,
5357        RedeclChainShouldBeCorrectAmongstNamespaces) {
5358   Decl *FromTU = getTuDecl(
5359       R"(
5360       namespace NS {
5361         struct X;
5362         struct Y {
5363           static const int I = 3;
5364         };
5365       }
5366       namespace NS {
5367         struct X {  // <--- To be imported
5368           void method(int i = Y::I) {}
5369           int f;
5370         };
5371       }
5372       )",
5373       Lang_CXX03);
5374   auto *FromFwd = FirstDeclMatcher<CXXRecordDecl>().match(
5375       FromTU, cxxRecordDecl(hasName("X"), unless(isImplicit())));
5376   auto *FromDef = LastDeclMatcher<CXXRecordDecl>().match(
5377       FromTU,
5378       cxxRecordDecl(hasName("X"), isDefinition(), unless(isImplicit())));
5379   ASSERT_NE(FromFwd, FromDef);
5380   ASSERT_FALSE(FromFwd->isThisDeclarationADefinition());
5381   ASSERT_TRUE(FromDef->isThisDeclarationADefinition());
5382   ASSERT_EQ(FromFwd->getCanonicalDecl(), FromDef->getCanonicalDecl());
5383 
5384   auto *ToDef = cast_or_null<CXXRecordDecl>(Import(FromDef, Lang_CXX03));
5385   auto *ToFwd = cast_or_null<CXXRecordDecl>(Import(FromFwd, Lang_CXX03));
5386   EXPECT_NE(ToFwd, ToDef);
5387   EXPECT_FALSE(ToFwd->isThisDeclarationADefinition());
5388   EXPECT_TRUE(ToDef->isThisDeclarationADefinition());
5389   EXPECT_EQ(ToFwd->getCanonicalDecl(), ToDef->getCanonicalDecl());
5390   auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
5391   // We expect no (ODR) warning during the import.
5392   EXPECT_EQ(0u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
5393 }
5394 
5395 struct ImportFriendFunctionTemplates : ASTImporterOptionSpecificTestBase {};
5396 
5397 TEST_P(ImportFriendFunctionTemplates, LookupShouldFindPreviousFriend) {
5398   Decl *ToTU = getToTuDecl(
5399       R"(
5400       class X {
5401         template <typename T> friend void foo();
5402       };
5403       )",
5404       Lang_CXX03);
5405   auto *Friend = FirstDeclMatcher<FunctionTemplateDecl>().match(
5406       ToTU, functionTemplateDecl(hasName("foo")));
5407 
5408   Decl *FromTU = getTuDecl(
5409       R"(
5410       template <typename T> void foo();
5411       )",
5412       Lang_CXX03);
5413   auto *FromFoo = FirstDeclMatcher<FunctionTemplateDecl>().match(
5414       FromTU, functionTemplateDecl(hasName("foo")));
5415   auto *Imported = Import(FromFoo, Lang_CXX03);
5416 
5417   EXPECT_EQ(Imported->getPreviousDecl(), Friend);
5418 }
5419 
5420 struct ASTImporterWithFakeErrors : ASTImporter {
5421   using ASTImporter::ASTImporter;
5422   bool returnWithErrorInTest() override { return true; }
5423 };
5424 
5425 struct ErrorHandlingTest : ASTImporterOptionSpecificTestBase {
5426   ErrorHandlingTest() {
5427     Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
5428                  ASTContext &FromContext, FileManager &FromFileManager,
5429                  bool MinimalImport,
5430                  const std::shared_ptr<ASTImporterSharedState> &SharedState) {
5431       return new ASTImporterWithFakeErrors(ToContext, ToFileManager,
5432                                            FromContext, FromFileManager,
5433                                            MinimalImport, SharedState);
5434     };
5435   }
5436   // In this test we purposely report an error (UnsupportedConstruct) when
5437   // importing the below stmt.
5438   static constexpr auto* ErroneousStmt = R"( asm(""); )";
5439 };
5440 
5441 // Check a case when no new AST node is created in the AST before encountering
5442 // the error.
5443 TEST_P(ErrorHandlingTest, ErrorHappensBeforeCreatingANewNode) {
5444   TranslationUnitDecl *ToTU = getToTuDecl(
5445       R"(
5446       template <typename T>
5447       class X {};
5448       template <>
5449       class X<int> { int a; };
5450       )",
5451       Lang_CXX03);
5452   TranslationUnitDecl *FromTU = getTuDecl(
5453       R"(
5454       template <typename T>
5455       class X {};
5456       template <>
5457       class X<int> { double b; };
5458       )",
5459       Lang_CXX03);
5460   auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
5461       FromTU, classTemplateSpecializationDecl(hasName("X")));
5462   ClassTemplateSpecializationDecl *ImportedSpec = Import(FromSpec, Lang_CXX03);
5463   EXPECT_FALSE(ImportedSpec);
5464 
5465   // The original Decl is kept, no new decl is created.
5466   EXPECT_EQ(DeclCounter<ClassTemplateSpecializationDecl>().match(
5467                 ToTU, classTemplateSpecializationDecl(hasName("X"))),
5468             1u);
5469 
5470   // But an error is set to the counterpart in the "from" context.
5471   ASTImporter *Importer = findFromTU(FromSpec)->Importer.get();
5472   Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromSpec);
5473   ASSERT_TRUE(OptErr);
5474   EXPECT_EQ(OptErr->Error, ASTImportError::NameConflict);
5475 }
5476 
5477 // Check a case when a new AST node is created but not linked to the AST before
5478 // encountering the error.
5479 TEST_P(ErrorHandlingTest,
5480        ErrorHappensAfterCreatingTheNodeButBeforeLinkingThatToTheAST) {
5481   TranslationUnitDecl *FromTU = getTuDecl(
5482       std::string("void foo() { ") + ErroneousStmt + " }", Lang_CXX03);
5483   auto *FromFoo = FirstDeclMatcher<FunctionDecl>().match(
5484       FromTU, functionDecl(hasName("foo")));
5485 
5486   FunctionDecl *ImportedFoo = Import(FromFoo, Lang_CXX03);
5487   EXPECT_FALSE(ImportedFoo);
5488 
5489   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
5490   // Created, but not linked.
5491   EXPECT_EQ(
5492       DeclCounter<FunctionDecl>().match(ToTU, functionDecl(hasName("foo"))),
5493       0u);
5494 
5495   ASTImporter *Importer = findFromTU(FromFoo)->Importer.get();
5496   Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromFoo);
5497   ASSERT_TRUE(OptErr);
5498   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5499 }
5500 
5501 // Check a case when a new AST node is created and linked to the AST before
5502 // encountering the error. The error is set for the counterpart of the nodes in
5503 // the "from" context.
5504 TEST_P(ErrorHandlingTest, ErrorHappensAfterNodeIsCreatedAndLinked) {
5505   TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5506       void f();
5507       void f() { )") + ErroneousStmt + R"( }
5508       )",
5509                                           Lang_CXX03);
5510   auto *FromProto = FirstDeclMatcher<FunctionDecl>().match(
5511       FromTU, functionDecl(hasName("f")));
5512   auto *FromDef =
5513       LastDeclMatcher<FunctionDecl>().match(FromTU, functionDecl(hasName("f")));
5514   FunctionDecl *ImportedProto = Import(FromProto, Lang_CXX03);
5515   EXPECT_FALSE(ImportedProto); // Could not import.
5516   // However, we created two nodes in the AST. 1) the fwd decl 2) the
5517   // definition. The definition is not added to its DC, but the fwd decl is
5518   // there.
5519   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
5520   EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, functionDecl(hasName("f"))),
5521             1u);
5522   // Match the fwd decl.
5523   auto *ToProto =
5524       FirstDeclMatcher<FunctionDecl>().match(ToTU, functionDecl(hasName("f")));
5525   EXPECT_TRUE(ToProto);
5526   // An error is set to the counterpart in the "from" context both for the fwd
5527   // decl and the definition.
5528   ASTImporter *Importer = findFromTU(FromProto)->Importer.get();
5529   Optional<ASTImportError> OptErr =
5530       Importer->getImportDeclErrorIfAny(FromProto);
5531   ASSERT_TRUE(OptErr);
5532   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5533   OptErr = Importer->getImportDeclErrorIfAny(FromDef);
5534   ASSERT_TRUE(OptErr);
5535   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5536 }
5537 
5538 // An error should be set for a class if we cannot import one member.
5539 TEST_P(ErrorHandlingTest, ErrorIsPropagatedFromMemberToClass) {
5540   TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5541       class X {
5542         void f() { )") + ErroneousStmt + R"( } // This member has the error
5543                                                // during import.
5544         void ok();        // The error should not prevent importing this.
5545       };                  // An error will be set for X too.
5546       )",
5547                                           Lang_CXX03);
5548   auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
5549       FromTU, cxxRecordDecl(hasName("X")));
5550   CXXRecordDecl *ImportedX = Import(FromX, Lang_CXX03);
5551 
5552   // An error is set for X.
5553   EXPECT_FALSE(ImportedX);
5554   ASTImporter *Importer = findFromTU(FromX)->Importer.get();
5555   Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromX);
5556   ASSERT_TRUE(OptErr);
5557   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5558 
5559   // An error is set for f().
5560   auto *FromF = FirstDeclMatcher<CXXMethodDecl>().match(
5561       FromTU, cxxMethodDecl(hasName("f")));
5562   OptErr = Importer->getImportDeclErrorIfAny(FromF);
5563   ASSERT_TRUE(OptErr);
5564   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5565   // And any subsequent import should fail.
5566   CXXMethodDecl *ImportedF = Import(FromF, Lang_CXX03);
5567   EXPECT_FALSE(ImportedF);
5568 
5569   // There is an error set for the other member too.
5570   auto *FromOK = FirstDeclMatcher<CXXMethodDecl>().match(
5571       FromTU, cxxMethodDecl(hasName("ok")));
5572   OptErr = Importer->getImportDeclErrorIfAny(FromOK);
5573   EXPECT_TRUE(OptErr);
5574   // Cannot import the other member.
5575   CXXMethodDecl *ImportedOK = Import(FromOK, Lang_CXX03);
5576   EXPECT_FALSE(ImportedOK);
5577 }
5578 
5579 // Check that an error propagates to the dependent AST nodes.
5580 // In the below code it means that an error in X should propagate to A.
5581 // And even to F since the containing A is erroneous.
5582 // And to all AST nodes which we visit during the import process which finally
5583 // ends up in a failure (in the error() function).
5584 TEST_P(ErrorHandlingTest, ErrorPropagatesThroughImportCycles) {
5585   Decl *FromTU = getTuDecl(std::string(R"(
5586       namespace NS {
5587         class A {
5588           template <int I> class F {};
5589           class X {
5590             template <int I> friend class F;
5591             void error() { )") +
5592                                ErroneousStmt + R"( }
5593           };
5594         };
5595 
5596         class B {};
5597       } // NS
5598       )",
5599                            Lang_CXX03, "input0.cc");
5600 
5601   auto *FromFRD = FirstDeclMatcher<CXXRecordDecl>().match(
5602       FromTU, cxxRecordDecl(hasName("F"), isDefinition()));
5603   auto *FromA = FirstDeclMatcher<CXXRecordDecl>().match(
5604       FromTU, cxxRecordDecl(hasName("A"), isDefinition()));
5605   auto *FromB = FirstDeclMatcher<CXXRecordDecl>().match(
5606       FromTU, cxxRecordDecl(hasName("B"), isDefinition()));
5607   auto *FromNS = FirstDeclMatcher<NamespaceDecl>().match(
5608       FromTU, namespaceDecl(hasName("NS")));
5609 
5610   // Start by importing the templated CXXRecordDecl of F.
5611   // Import fails for that.
5612   EXPECT_FALSE(Import(FromFRD, Lang_CXX03));
5613   // Import fails for A.
5614   EXPECT_FALSE(Import(FromA, Lang_CXX03));
5615   // But we should be able to import the independent B.
5616   EXPECT_TRUE(Import(FromB, Lang_CXX03));
5617   // And the namespace.
5618   EXPECT_TRUE(Import(FromNS, Lang_CXX03));
5619 
5620   // An error is set to the templated CXXRecordDecl of F.
5621   ASTImporter *Importer = findFromTU(FromFRD)->Importer.get();
5622   Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromFRD);
5623   EXPECT_TRUE(OptErr);
5624 
5625   // An error is set to A.
5626   OptErr = Importer->getImportDeclErrorIfAny(FromA);
5627   EXPECT_TRUE(OptErr);
5628 
5629   // There is no error set to B.
5630   OptErr = Importer->getImportDeclErrorIfAny(FromB);
5631   EXPECT_FALSE(OptErr);
5632 
5633   // There is no error set to NS.
5634   OptErr = Importer->getImportDeclErrorIfAny(FromNS);
5635   EXPECT_FALSE(OptErr);
5636 
5637   // Check some of those decls whose ancestor is X, they all should have an
5638   // error set if we visited them during an import process which finally failed.
5639   // These decls are part of a cycle in an ImportPath.
5640   // There would not be any error set for these decls if we hadn't follow the
5641   // ImportPaths and the cycles.
5642   OptErr = Importer->getImportDeclErrorIfAny(
5643       FirstDeclMatcher<ClassTemplateDecl>().match(
5644           FromTU, classTemplateDecl(hasName("F"))));
5645   // An error is set to the 'F' ClassTemplateDecl.
5646   EXPECT_TRUE(OptErr);
5647   // An error is set to the FriendDecl.
5648   OptErr = Importer->getImportDeclErrorIfAny(
5649       FirstDeclMatcher<FriendDecl>().match(
5650           FromTU, friendDecl()));
5651   EXPECT_TRUE(OptErr);
5652   // An error is set to the implicit class of A.
5653   OptErr =
5654       Importer->getImportDeclErrorIfAny(FirstDeclMatcher<CXXRecordDecl>().match(
5655           FromTU, cxxRecordDecl(hasName("A"), isImplicit())));
5656   EXPECT_TRUE(OptErr);
5657   // An error is set to the implicit class of X.
5658   OptErr =
5659       Importer->getImportDeclErrorIfAny(FirstDeclMatcher<CXXRecordDecl>().match(
5660           FromTU, cxxRecordDecl(hasName("X"), isImplicit())));
5661   EXPECT_TRUE(OptErr);
5662 }
5663 
5664 TEST_P(ErrorHandlingTest, ErrorIsNotPropagatedFromMemberToNamespace) {
5665   TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5666       namespace X {
5667         void f() { )") + ErroneousStmt + R"( } // This member has the error
5668                                                // during import.
5669         void ok();        // The error should not prevent importing this.
5670       };                  // An error will be set for X too.
5671       )",
5672                                           Lang_CXX03);
5673   auto *FromX = FirstDeclMatcher<NamespaceDecl>().match(
5674       FromTU, namespaceDecl(hasName("X")));
5675   NamespaceDecl *ImportedX = Import(FromX, Lang_CXX03);
5676 
5677   // There is no error set for X.
5678   EXPECT_TRUE(ImportedX);
5679   ASTImporter *Importer = findFromTU(FromX)->Importer.get();
5680   Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromX);
5681   ASSERT_FALSE(OptErr);
5682 
5683   // An error is set for f().
5684   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
5685       FromTU, functionDecl(hasName("f")));
5686   OptErr = Importer->getImportDeclErrorIfAny(FromF);
5687   ASSERT_TRUE(OptErr);
5688   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5689   // And any subsequent import should fail.
5690   FunctionDecl *ImportedF = Import(FromF, Lang_CXX03);
5691   EXPECT_FALSE(ImportedF);
5692 
5693   // There is no error set for ok().
5694   auto *FromOK = FirstDeclMatcher<FunctionDecl>().match(
5695       FromTU, functionDecl(hasName("ok")));
5696   OptErr = Importer->getImportDeclErrorIfAny(FromOK);
5697   EXPECT_FALSE(OptErr);
5698   // And we should be able to import.
5699   FunctionDecl *ImportedOK = Import(FromOK, Lang_CXX03);
5700   EXPECT_TRUE(ImportedOK);
5701 }
5702 
5703 TEST_P(ErrorHandlingTest, ODRViolationWithinTypedefDecls) {
5704   // Importing `z` should fail - instead of crashing - due to an ODR violation.
5705   // The `bar::e` typedef sets it's DeclContext after the import is done.
5706   // However, if the importation fails, it will be left as a nullptr.
5707   // During the cleanup of the failed import, we should check whether the
5708   // DeclContext is null or not - instead of dereferencing that unconditionally.
5709   constexpr auto ToTUCode = R"(
5710       namespace X {
5711         struct bar {
5712           int odr_violation;
5713         };
5714       })";
5715   constexpr auto FromTUCode = R"(
5716       namespace X {
5717         enum b {};
5718         struct bar {
5719           typedef b e;
5720           static e d;
5721         };
5722       }
5723       int z = X::bar::d;
5724       )";
5725   Decl *ToTU = getToTuDecl(ToTUCode, Lang_CXX11);
5726   static_cast<void>(ToTU);
5727   Decl *FromTU = getTuDecl(FromTUCode, Lang_CXX11);
5728   auto *FromZ =
5729       FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("z")));
5730   ASSERT_TRUE(FromZ);
5731   ASSERT_TRUE(FromZ->hasInit());
5732 
5733   auto *ImportedZ = Import(FromZ, Lang_CXX11);
5734   EXPECT_FALSE(ImportedZ);
5735 }
5736 
5737 // An error should be set for a class if it had a previous import with an error
5738 // from another TU.
5739 TEST_P(ErrorHandlingTest,
5740        ImportedDeclWithErrorShouldFailTheImportOfDeclWhichMapToIt) {
5741   // We already have a fwd decl.
5742   TranslationUnitDecl *ToTU = getToTuDecl("class X;", Lang_CXX03);
5743   // Then we import a definition.
5744   {
5745     TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5746         class X {
5747           void f() { )") + ErroneousStmt + R"( }
5748           void ok();
5749         };
5750         )",
5751                                             Lang_CXX03);
5752     auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
5753         FromTU, cxxRecordDecl(hasName("X")));
5754     CXXRecordDecl *ImportedX = Import(FromX, Lang_CXX03);
5755 
5756     // An error is set for X ...
5757     EXPECT_FALSE(ImportedX);
5758     ASTImporter *Importer = findFromTU(FromX)->Importer.get();
5759     Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromX);
5760     ASSERT_TRUE(OptErr);
5761     EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5762   }
5763   // ... but the node had been created.
5764   auto *ToXDef = FirstDeclMatcher<CXXRecordDecl>().match(
5765       ToTU, cxxRecordDecl(hasName("X"), isDefinition()));
5766   // An error is set for "ToXDef" in the shared state.
5767   Optional<ASTImportError> OptErr =
5768       SharedStatePtr->getImportDeclErrorIfAny(ToXDef);
5769   ASSERT_TRUE(OptErr);
5770   EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5771 
5772   auto *ToXFwd = FirstDeclMatcher<CXXRecordDecl>().match(
5773       ToTU, cxxRecordDecl(hasName("X"), unless(isDefinition())));
5774   // An error is NOT set for the fwd Decl of X in the shared state.
5775   OptErr = SharedStatePtr->getImportDeclErrorIfAny(ToXFwd);
5776   ASSERT_FALSE(OptErr);
5777 
5778   // Try to import  X again but from another TU.
5779   {
5780     TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5781         class X {
5782           void f() { )") + ErroneousStmt + R"( }
5783           void ok();
5784         };
5785         )",
5786                                             Lang_CXX03, "input1.cc");
5787 
5788     auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
5789         FromTU, cxxRecordDecl(hasName("X")));
5790     CXXRecordDecl *ImportedX = Import(FromX, Lang_CXX03);
5791 
5792     // If we did not save the errors for the "to" context then the below checks
5793     // would fail, because the lookup finds the fwd Decl of the existing
5794     // definition in the "to" context. We can reach the existing definition via
5795     // the found fwd Decl. That existing definition is structurally equivalent
5796     // (we check only the fields) with this one we want to import, so we return
5797     // with the existing definition, which is erroneous (one method is missing).
5798 
5799     // The import should fail.
5800     EXPECT_FALSE(ImportedX);
5801     ASTImporter *Importer = findFromTU(FromX)->Importer.get();
5802     Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromX);
5803     // And an error is set for this new X in the "from" ctx.
5804     ASSERT_TRUE(OptErr);
5805     EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5806   }
5807 }
5808 
5809 TEST_P(ErrorHandlingTest, ImportOfOverriddenMethods) {
5810   auto MatchFooA =
5811       functionDecl(hasName("foo"), hasAncestor(cxxRecordDecl(hasName("A"))));
5812   auto MatchFooB =
5813       functionDecl(hasName("foo"), hasAncestor(cxxRecordDecl(hasName("B"))));
5814   auto MatchFooC =
5815       functionDecl(hasName("foo"), hasAncestor(cxxRecordDecl(hasName("C"))));
5816 
5817   // Provoke import of a method that has overridden methods with import error.
5818   TranslationUnitDecl *FromTU = getTuDecl(std::string(R"(
5819         struct C;
5820         struct A {
5821           virtual void foo();
5822           void f1(C *);
5823         };
5824         void A::foo() {
5825           )") + ErroneousStmt + R"(
5826         }
5827         struct B : public A {
5828           void foo() override;
5829         };
5830         struct C : public B {
5831           void foo() override;
5832         };
5833         )",
5834                                           Lang_CXX11);
5835   auto *FromFooA = FirstDeclMatcher<FunctionDecl>().match(FromTU, MatchFooA);
5836   auto *FromFooB = FirstDeclMatcher<FunctionDecl>().match(FromTU, MatchFooB);
5837   auto *FromFooC = FirstDeclMatcher<FunctionDecl>().match(FromTU, MatchFooC);
5838 
5839   EXPECT_FALSE(Import(FromFooA, Lang_CXX11));
5840   ASTImporter *Importer = findFromTU(FromFooA)->Importer.get();
5841   auto CheckError = [&Importer](Decl *FromD) {
5842     Optional<ASTImportError> OptErr = Importer->getImportDeclErrorIfAny(FromD);
5843     ASSERT_TRUE(OptErr);
5844     EXPECT_EQ(OptErr->Error, ASTImportError::UnsupportedConstruct);
5845   };
5846   CheckError(FromFooA);
5847   EXPECT_FALSE(Import(FromFooB, Lang_CXX11));
5848   CheckError(FromFooB);
5849   EXPECT_FALSE(Import(FromFooC, Lang_CXX11));
5850   CheckError(FromFooC);
5851 }
5852 
5853 TEST_P(ErrorHandlingTest, ODRViolationWithinParmVarDecls) {
5854   // Importing of 'f' and parameter 'P' should cause an ODR error.
5855   // The error happens after the ParmVarDecl for 'P' was already created.
5856   // This is a special case because the ParmVarDecl has a temporary DeclContext.
5857   // Expected is no crash at error handling of ASTImporter.
5858   constexpr auto ToTUCode = R"(
5859       struct X {
5860         char A;
5861       };
5862       )";
5863   constexpr auto FromTUCode = R"(
5864       struct X {
5865         enum Y { Z };
5866       };
5867       void f(int P = X::Z);
5868       )";
5869   Decl *ToTU = getToTuDecl(ToTUCode, Lang_CXX11);
5870   static_cast<void>(ToTU);
5871   Decl *FromTU = getTuDecl(FromTUCode, Lang_CXX11);
5872   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
5873       FromTU, functionDecl(hasName("f")));
5874   ASSERT_TRUE(FromF);
5875 
5876   auto *ImportedF = Import(FromF, Lang_CXX11);
5877   EXPECT_FALSE(ImportedF);
5878 }
5879 
5880 TEST_P(ErrorHandlingTest, DoNotInheritErrorFromNonDependentChild) {
5881   // Declarations should not inherit an import error from a child object
5882   // if the declaration has no direct dependence to such a child.
5883   // For example a namespace should not get import error if one of the
5884   // declarations inside it fails to import.
5885   // There was a special case in error handling (when "import path circles" are
5886   // encountered) when this property was not held. This case is provoked by the
5887   // following code.
5888   constexpr auto ToTUCode = R"(
5889       namespace ns {
5890         struct Err {
5891           char A;
5892         };
5893       }
5894       )";
5895   constexpr auto FromTUCode = R"(
5896       namespace ns {
5897         struct A {
5898           using U = struct Err;
5899         };
5900       }
5901       namespace ns {
5902         struct Err {}; // ODR violation
5903         void f(A) {}
5904       }
5905       )";
5906 
5907   Decl *ToTU = getToTuDecl(ToTUCode, Lang_CXX11);
5908   static_cast<void>(ToTU);
5909   Decl *FromTU = getTuDecl(FromTUCode, Lang_CXX11);
5910   auto *FromA = FirstDeclMatcher<CXXRecordDecl>().match(
5911       FromTU, cxxRecordDecl(hasName("A"), hasDefinition()));
5912   ASSERT_TRUE(FromA);
5913   auto *ImportedA = Import(FromA, Lang_CXX11);
5914   // 'A' can not be imported: ODR error at 'Err'
5915   EXPECT_FALSE(ImportedA);
5916   // When import of 'A' failed there was a "saved import path circle" that
5917   // contained namespace 'ns' (A - U - Err - ns - f - A). This should not mean
5918   // that every object in this path fails to import.
5919 
5920   Decl *FromNS = FirstDeclMatcher<NamespaceDecl>().match(
5921       FromTU, namespaceDecl(hasName("ns")));
5922   EXPECT_TRUE(FromNS);
5923   auto *ImportedNS = Import(FromNS, Lang_CXX11);
5924   EXPECT_TRUE(ImportedNS);
5925 }
5926 
5927 TEST_P(ASTImporterOptionSpecificTestBase, LambdaInFunctionBody) {
5928   Decl *FromTU = getTuDecl(
5929       R"(
5930       void f() {
5931         auto L = [](){};
5932       }
5933       )",
5934       Lang_CXX11, "input0.cc");
5935   auto Pattern = lambdaExpr();
5936   CXXRecordDecl *FromL =
5937       FirstDeclMatcher<LambdaExpr>().match(FromTU, Pattern)->getLambdaClass();
5938 
5939   auto ToL = Import(FromL, Lang_CXX11);
5940   unsigned ToLSize = std::distance(ToL->decls().begin(), ToL->decls().end());
5941   unsigned FromLSize =
5942       std::distance(FromL->decls().begin(), FromL->decls().end());
5943   EXPECT_NE(ToLSize, 0u);
5944   EXPECT_EQ(ToLSize, FromLSize);
5945   EXPECT_FALSE(FromL->isDependentLambda());
5946 }
5947 
5948 TEST_P(ASTImporterOptionSpecificTestBase, LambdaInFunctionParam) {
5949   Decl *FromTU = getTuDecl(
5950       R"(
5951       template <typename F>
5952       void f(F L = [](){}) {}
5953       )",
5954       Lang_CXX11, "input0.cc");
5955   auto Pattern = lambdaExpr();
5956   CXXRecordDecl *FromL =
5957       FirstDeclMatcher<LambdaExpr>().match(FromTU, Pattern)->getLambdaClass();
5958 
5959   auto ToL = Import(FromL, Lang_CXX11);
5960   unsigned ToLSize = std::distance(ToL->decls().begin(), ToL->decls().end());
5961   unsigned FromLSize =
5962       std::distance(FromL->decls().begin(), FromL->decls().end());
5963   EXPECT_NE(ToLSize, 0u);
5964   EXPECT_EQ(ToLSize, FromLSize);
5965   EXPECT_TRUE(FromL->isDependentLambda());
5966 }
5967 
5968 TEST_P(ASTImporterOptionSpecificTestBase, LambdaInGlobalScope) {
5969   Decl *FromTU = getTuDecl(
5970       R"(
5971       auto l1 = [](unsigned lp) { return 1; };
5972       auto l2 = [](int lp) { return 2; };
5973       int f(int p) {
5974         return l1(p) + l2(p);
5975       }
5976       )",
5977       Lang_CXX11, "input0.cc");
5978   FunctionDecl *FromF = FirstDeclMatcher<FunctionDecl>().match(
5979       FromTU, functionDecl(hasName("f")));
5980   FunctionDecl *ToF = Import(FromF, Lang_CXX11);
5981   EXPECT_TRUE(ToF);
5982 }
5983 
5984 TEST_P(ASTImporterOptionSpecificTestBase,
5985        ImportExistingFriendClassTemplateDef) {
5986   auto Code =
5987       R"(
5988         template <class T1, class T2>
5989         struct Base {
5990           template <class U1, class U2>
5991           friend struct Class;
5992         };
5993         template <class T1, class T2>
5994         struct Class { };
5995         )";
5996 
5997   TranslationUnitDecl *ToTU = getToTuDecl(Code, Lang_CXX03);
5998   TranslationUnitDecl *FromTU = getTuDecl(Code, Lang_CXX03, "input.cc");
5999 
6000   auto *ToClassProto = FirstDeclMatcher<ClassTemplateDecl>().match(
6001       ToTU, classTemplateDecl(hasName("Class")));
6002   auto *ToClassDef = LastDeclMatcher<ClassTemplateDecl>().match(
6003       ToTU, classTemplateDecl(hasName("Class")));
6004   ASSERT_FALSE(ToClassProto->isThisDeclarationADefinition());
6005   ASSERT_TRUE(ToClassDef->isThisDeclarationADefinition());
6006   // Previous friend decl is not linked to it!
6007   ASSERT_FALSE(ToClassDef->getPreviousDecl());
6008   ASSERT_EQ(ToClassDef->getMostRecentDecl(), ToClassDef);
6009   ASSERT_EQ(ToClassProto->getMostRecentDecl(), ToClassProto);
6010 
6011   auto *FromClassProto = FirstDeclMatcher<ClassTemplateDecl>().match(
6012       FromTU, classTemplateDecl(hasName("Class")));
6013   auto *FromClassDef = LastDeclMatcher<ClassTemplateDecl>().match(
6014       FromTU, classTemplateDecl(hasName("Class")));
6015   ASSERT_FALSE(FromClassProto->isThisDeclarationADefinition());
6016   ASSERT_TRUE(FromClassDef->isThisDeclarationADefinition());
6017   ASSERT_FALSE(FromClassDef->getPreviousDecl());
6018   ASSERT_EQ(FromClassDef->getMostRecentDecl(), FromClassDef);
6019   ASSERT_EQ(FromClassProto->getMostRecentDecl(), FromClassProto);
6020 
6021   auto *ImportedDef = Import(FromClassDef, Lang_CXX03);
6022   // At import we should find the definition for 'Class' even if the
6023   // prototype (inside 'friend') for it comes first in the AST and is not
6024   // linked to the definition.
6025   EXPECT_EQ(ImportedDef, ToClassDef);
6026 }
6027 
6028 struct LLDBLookupTest : ASTImporterOptionSpecificTestBase {
6029   LLDBLookupTest() {
6030     Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
6031                  ASTContext &FromContext, FileManager &FromFileManager,
6032                  bool MinimalImport,
6033                  const std::shared_ptr<ASTImporterSharedState> &SharedState) {
6034       return new ASTImporter(ToContext, ToFileManager, FromContext,
6035                              FromFileManager, MinimalImport,
6036                              // We use the regular lookup.
6037                              /*SharedState=*/nullptr);
6038     };
6039   }
6040 };
6041 
6042 TEST_P(LLDBLookupTest, ImporterShouldFindInTransparentContext) {
6043   TranslationUnitDecl *ToTU = getToTuDecl(
6044       R"(
6045       extern "C" {
6046         class X{};
6047       };
6048       )",
6049       Lang_CXX03);
6050   auto *ToX = FirstDeclMatcher<CXXRecordDecl>().match(
6051       ToTU, cxxRecordDecl(hasName("X")));
6052 
6053   // Set up a stub external storage.
6054   ToTU->setHasExternalLexicalStorage(true);
6055   // Set up DeclContextBits.HasLazyExternalLexicalLookups to true.
6056   ToTU->setMustBuildLookupTable();
6057   struct TestExternalASTSource : ExternalASTSource {};
6058   ToTU->getASTContext().setExternalSource(new TestExternalASTSource());
6059 
6060   Decl *FromTU = getTuDecl(
6061       R"(
6062         class X;
6063       )",
6064       Lang_CXX03);
6065   auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
6066       FromTU, cxxRecordDecl(hasName("X")));
6067   auto *ImportedX = Import(FromX, Lang_CXX03);
6068   // The lookup must find the existing class definition in the LinkageSpecDecl.
6069   // Then the importer renders the existing and the new decl into one chain.
6070   EXPECT_EQ(ImportedX->getCanonicalDecl(), ToX->getCanonicalDecl());
6071 }
6072 
6073 struct SVEBuiltins : ASTImporterOptionSpecificTestBase {};
6074 
6075 TEST_P(SVEBuiltins, ImportTypes) {
6076   static const char *const TypeNames[] = {
6077     "__SVInt8_t",
6078     "__SVInt16_t",
6079     "__SVInt32_t",
6080     "__SVInt64_t",
6081     "__SVUint8_t",
6082     "__SVUint16_t",
6083     "__SVUint32_t",
6084     "__SVUint64_t",
6085     "__SVFloat16_t",
6086     "__SVBFloat16_t",
6087     "__SVFloat32_t",
6088     "__SVFloat64_t",
6089     "__SVBool_t"
6090   };
6091 
6092   TranslationUnitDecl *ToTU = getToTuDecl("", Lang_CXX03);
6093   TranslationUnitDecl *FromTU = getTuDecl("", Lang_CXX03, "input.cc");
6094   for (auto *TypeName : TypeNames) {
6095     auto *ToTypedef = FirstDeclMatcher<TypedefDecl>().match(
6096       ToTU, typedefDecl(hasName(TypeName)));
6097     QualType ToType = ToTypedef->getUnderlyingType();
6098 
6099     auto *FromTypedef = FirstDeclMatcher<TypedefDecl>().match(
6100       FromTU, typedefDecl(hasName(TypeName)));
6101     QualType FromType = FromTypedef->getUnderlyingType();
6102 
6103     QualType ImportedType = ImportType(FromType, FromTypedef, Lang_CXX03);
6104     EXPECT_EQ(ImportedType, ToType);
6105   }
6106 }
6107 
6108 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfDefaultImplicitFunctions) {
6109   // Test that import of implicit functions works and the functions
6110   // are merged into one chain.
6111   auto GetDeclToImport = [this](StringRef File) {
6112     Decl *FromTU = getTuDecl(
6113         R"(
6114         struct X { };
6115         // Force generating some implicit operator definitions for X.
6116         void f() { X x1, x2; x1 = x2; X *x3 = new X; delete x3; }
6117         )",
6118         Lang_CXX11, File);
6119     auto *FromD = FirstDeclMatcher<CXXRecordDecl>().match(
6120         FromTU, cxxRecordDecl(hasName("X"), unless(isImplicit())));
6121     // Destructor is picked as one example of implicit function.
6122     return FromD->getDestructor();
6123   };
6124 
6125   auto *ToD1 = Import(GetDeclToImport("input1.cc"), Lang_CXX11);
6126   ASSERT_TRUE(ToD1);
6127 
6128   auto *ToD2 = Import(GetDeclToImport("input2.cc"), Lang_CXX11);
6129   ASSERT_TRUE(ToD2);
6130 
6131   EXPECT_EQ(ToD1->getCanonicalDecl(), ToD2->getCanonicalDecl());
6132 }
6133 
6134 TEST_P(ASTImporterOptionSpecificTestBase,
6135        ImportOfExplicitlyDefaultedOrDeleted) {
6136   Decl *FromTU = getTuDecl(
6137       R"(
6138         struct X { X() = default; X(const X&) = delete; };
6139       )",
6140       Lang_CXX11);
6141   auto *FromX = FirstDeclMatcher<CXXRecordDecl>().match(
6142       FromTU, cxxRecordDecl(hasName("X")));
6143   auto *ImportedX = Import(FromX, Lang_CXX11);
6144   auto *Constr1 = FirstDeclMatcher<CXXConstructorDecl>().match(
6145       ImportedX, cxxConstructorDecl(hasName("X"), unless(isImplicit())));
6146   auto *Constr2 = LastDeclMatcher<CXXConstructorDecl>().match(
6147       ImportedX, cxxConstructorDecl(hasName("X"), unless(isImplicit())));
6148 
6149   ASSERT_TRUE(ImportedX);
6150   EXPECT_TRUE(Constr1->isDefaulted());
6151   EXPECT_TRUE(Constr1->isExplicitlyDefaulted());
6152   EXPECT_TRUE(Constr2->isDeletedAsWritten());
6153   EXPECT_EQ(ImportedX->isAggregate(), FromX->isAggregate());
6154 }
6155 
6156 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, SVEBuiltins,
6157                          ::testing::Values(std::vector<std::string>{
6158                              "-target", "aarch64-linux-gnu"}));
6159 
6160 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, DeclContextTest,
6161                          ::testing::Values(std::vector<std::string>()));
6162 
6163 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, CanonicalRedeclChain,
6164                          ::testing::Values(std::vector<std::string>()));
6165 
6166 TEST_P(ASTImporterOptionSpecificTestBase, LambdasAreDifferentiated) {
6167   Decl *FromTU = getTuDecl(
6168       R"(
6169       void f() {
6170         auto L0 = [](){};
6171         auto L1 = [](){};
6172       }
6173       )",
6174       Lang_CXX11, "input0.cc");
6175   auto Pattern = lambdaExpr();
6176   CXXRecordDecl *FromL0 =
6177       FirstDeclMatcher<LambdaExpr>().match(FromTU, Pattern)->getLambdaClass();
6178   CXXRecordDecl *FromL1 =
6179       LastDeclMatcher<LambdaExpr>().match(FromTU, Pattern)->getLambdaClass();
6180   ASSERT_NE(FromL0, FromL1);
6181 
6182   CXXRecordDecl *ToL0 = Import(FromL0, Lang_CXX11);
6183   CXXRecordDecl *ToL1 = Import(FromL1, Lang_CXX11);
6184   EXPECT_NE(ToL0, ToL1);
6185 }
6186 
6187 TEST_P(ASTImporterOptionSpecificTestBase,
6188        LambdasInFunctionParamsAreDifferentiated) {
6189   Decl *FromTU = getTuDecl(
6190       R"(
6191       template <typename F0, typename F1>
6192       void f(F0 L0 = [](){}, F1 L1 = [](){}) {}
6193       )",
6194       Lang_CXX11, "input0.cc");
6195   auto Pattern = cxxRecordDecl(isLambda());
6196   CXXRecordDecl *FromL0 =
6197       FirstDeclMatcher<CXXRecordDecl>().match(FromTU, Pattern);
6198   CXXRecordDecl *FromL1 =
6199       LastDeclMatcher<CXXRecordDecl>().match(FromTU, Pattern);
6200   ASSERT_NE(FromL0, FromL1);
6201 
6202   CXXRecordDecl *ToL0 = Import(FromL0, Lang_CXX11);
6203   CXXRecordDecl *ToL1 = Import(FromL1, Lang_CXX11);
6204   ASSERT_NE(ToL0, ToL1);
6205 }
6206 
6207 TEST_P(ASTImporterOptionSpecificTestBase,
6208        LambdasInFunctionParamsAreDifferentiatedWhenMacroIsUsed) {
6209   Decl *FromTU = getTuDecl(
6210       R"(
6211       #define LAMBDA [](){}
6212       template <typename F0, typename F1>
6213       void f(F0 L0 = LAMBDA, F1 L1 = LAMBDA) {}
6214       )",
6215       Lang_CXX11, "input0.cc");
6216   auto Pattern = cxxRecordDecl(isLambda());
6217   CXXRecordDecl *FromL0 =
6218       FirstDeclMatcher<CXXRecordDecl>().match(FromTU, Pattern);
6219   CXXRecordDecl *FromL1 =
6220       LastDeclMatcher<CXXRecordDecl>().match(FromTU, Pattern);
6221   ASSERT_NE(FromL0, FromL1);
6222 
6223   Import(FromL0, Lang_CXX11);
6224   Import(FromL1, Lang_CXX11);
6225   CXXRecordDecl *ToL0 = Import(FromL0, Lang_CXX11);
6226   CXXRecordDecl *ToL1 = Import(FromL1, Lang_CXX11);
6227   ASSERT_NE(ToL0, ToL1);
6228 }
6229 
6230 TEST_P(ASTImporterOptionSpecificTestBase, ImportAssignedLambda) {
6231   Decl *FromTU = getTuDecl(
6232       R"(
6233       void f() {
6234         auto x = []{} = {}; auto x2 = x;
6235       }
6236       )",
6237       Lang_CXX20, "input0.cc");
6238   auto FromF = FirstDeclMatcher<FunctionDecl>().match(
6239       FromTU, functionDecl(hasName("f")));
6240   // We have only one lambda class.
6241   ASSERT_EQ(
6242       DeclCounter<CXXRecordDecl>().match(FromTU, cxxRecordDecl(isLambda())),
6243       1u);
6244 
6245   FunctionDecl *ToF = Import(FromF, Lang_CXX20);
6246   EXPECT_TRUE(ToF);
6247   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
6248   // We have only one lambda class after the import.
6249   EXPECT_EQ(DeclCounter<CXXRecordDecl>().match(ToTU, cxxRecordDecl(isLambda())),
6250             1u);
6251 }
6252 
6253 TEST_P(ASTImporterOptionSpecificTestBase, ImportDefaultConstructibleLambdas) {
6254   Decl *FromTU = getTuDecl(
6255       R"(
6256       void f() {
6257         auto x = []{} = {};
6258         auto xb = []{} = {};
6259       }
6260       )",
6261       Lang_CXX20, "input0.cc");
6262   auto FromF = FirstDeclMatcher<FunctionDecl>().match(
6263       FromTU, functionDecl(hasName("f")));
6264   // We have two lambda classes.
6265   ASSERT_EQ(
6266       DeclCounter<CXXRecordDecl>().match(FromTU, cxxRecordDecl(isLambda())),
6267       2u);
6268 
6269   FunctionDecl *ToF = Import(FromF, Lang_CXX20);
6270   EXPECT_TRUE(ToF);
6271   TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
6272   // We have two lambda classes after the import.
6273   EXPECT_EQ(DeclCounter<CXXRecordDecl>().match(ToTU, cxxRecordDecl(isLambda())),
6274             2u);
6275 }
6276 
6277 TEST_P(ASTImporterOptionSpecificTestBase,
6278        ImportFunctionDeclWithTypeSourceInfoWithSourceDecl) {
6279   // This code results in a lambda with implicit constructor.
6280   // The constructor's TypeSourceInfo points out the function prototype.
6281   // This prototype has an EST_Unevaluated in its exception information and a
6282   // SourceDecl that is the function declaration itself.
6283   // The test verifies that AST import of such AST does not crash.
6284   // (Here the function's TypeSourceInfo references the function itself.)
6285   Decl *FromTU = getTuDecl(
6286       R"(
6287         template<typename T> void f(T) { auto X = [](){}; }
6288         void g() { f(10); }
6289         )",
6290       Lang_CXX11, "input0.cc");
6291 
6292   // Use LastDeclMatcher to find the LambdaExpr in the template specialization.
6293   CXXRecordDecl *FromL = LastDeclMatcher<LambdaExpr>()
6294                              .match(FromTU, lambdaExpr())
6295                              ->getLambdaClass();
6296 
6297   CXXConstructorDecl *FromCtor = *FromL->ctor_begin();
6298   ASSERT_TRUE(FromCtor->isCopyConstructor());
6299   ASSERT_TRUE(FromCtor->getTypeSourceInfo());
6300   const auto *FromFPT = FromCtor->getType()->getAs<FunctionProtoType>();
6301   ASSERT_TRUE(FromFPT);
6302   EXPECT_EQ(FromCtor->getTypeSourceInfo()->getType().getTypePtr(), FromFPT);
6303   FunctionProtoType::ExtProtoInfo FromEPI = FromFPT->getExtProtoInfo();
6304   // If type is EST_Unevaluated, SourceDecl should be set to the parent Decl.
6305   EXPECT_EQ(FromEPI.ExceptionSpec.Type, EST_Unevaluated);
6306   EXPECT_EQ(FromEPI.ExceptionSpec.SourceDecl, FromCtor);
6307 
6308   auto ToL = Import(FromL, Lang_CXX11);
6309 
6310   // Check if the import was correct.
6311   CXXConstructorDecl *ToCtor = *ToL->ctor_begin();
6312   EXPECT_TRUE(ToCtor->getTypeSourceInfo());
6313   const auto *ToFPT = ToCtor->getType()->getAs<FunctionProtoType>();
6314   ASSERT_TRUE(ToFPT);
6315   EXPECT_EQ(ToCtor->getTypeSourceInfo()->getType().getTypePtr(), ToFPT);
6316   FunctionProtoType::ExtProtoInfo ToEPI = ToFPT->getExtProtoInfo();
6317   EXPECT_EQ(ToEPI.ExceptionSpec.Type, EST_Unevaluated);
6318   EXPECT_EQ(ToEPI.ExceptionSpec.SourceDecl, ToCtor);
6319 }
6320 
6321 struct ImportAutoFunctions : ASTImporterOptionSpecificTestBase {};
6322 
6323 TEST_P(ImportAutoFunctions, ReturnWithTemplateWithStructDeclaredInside1) {
6324   Decl *FromTU = getTuDecl(
6325       R"(
6326       template<class> struct Tmpl {};
6327       auto foo() {
6328         struct X {};
6329         return Tmpl<X>();
6330       }
6331       )",
6332       Lang_CXX14, "input0.cc");
6333   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6334       FromTU, functionDecl(hasName("foo")));
6335 
6336   FunctionDecl *To = Import(From, Lang_CXX14);
6337   EXPECT_TRUE(To);
6338   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6339 }
6340 
6341 TEST_P(ImportAutoFunctions, ReturnWithTemplateWithStructDeclaredInside2) {
6342   Decl *FromTU = getTuDecl(
6343       R"(
6344       template<class> struct Tmpl {};
6345       auto foo() {
6346         struct X {};
6347         return Tmpl<Tmpl<X>>();
6348       }
6349       )",
6350       Lang_CXX14, "input0.cc");
6351   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6352       FromTU, functionDecl(hasName("foo")));
6353 
6354   FunctionDecl *To = Import(From, Lang_CXX14);
6355   EXPECT_TRUE(To);
6356   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6357 }
6358 
6359 TEST_P(ImportAutoFunctions, ReturnWithTemplateWithTypedefDeclaredInside) {
6360   Decl *FromTU = getTuDecl(
6361       R"(
6362       template<class> struct Tmpl {};
6363       auto foo() {
6364         struct X {};
6365         using x_type = X;
6366         return Tmpl<x_type>();
6367       }
6368       )",
6369       Lang_CXX14, "input0.cc");
6370   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6371       FromTU, functionDecl(hasName("foo")));
6372 
6373   FunctionDecl *To = Import(From, Lang_CXX14);
6374   EXPECT_TRUE(To);
6375   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6376 }
6377 
6378 TEST_P(ImportAutoFunctions, ReturnWithTypedefDeclaredInside) {
6379   Decl *FromTU = getTuDecl(
6380       R"(
6381       auto X = [](long l) {
6382         using int_type = long;
6383         auto dur = 13;
6384         return static_cast<int_type>(dur);
6385       };
6386       )",
6387       Lang_CXX14, "input0.cc");
6388   CXXMethodDecl *From =
6389       FirstDeclMatcher<CXXMethodDecl>().match(FromTU, cxxMethodDecl());
6390 
6391   // Explicitly set the return type of the lambda's operator() to the TypeAlias.
6392   // Normally the return type would be the built-in 'long' type. However, there
6393   // are cases when Clang does not use the canonical type and the TypeAlias is
6394   // used. I could not create such an AST from regular source code, it requires
6395   // some special state in the preprocessor. I've found such an AST when Clang
6396   // parsed libcxx/src/filesystem/directory_iterator.cpp, but could not reduce
6397   // that with creduce, because after preprocessing, the AST no longer
6398   // contained the TypeAlias as a return type of the lambda.
6399   ASTContext &Ctx = From->getASTContext();
6400   TypeAliasDecl *FromTA =
6401       FirstDeclMatcher<TypeAliasDecl>().match(FromTU, typeAliasDecl());
6402   QualType TT = Ctx.getTypedefType(FromTA);
6403   const FunctionProtoType *FPT = cast<FunctionProtoType>(From->getType());
6404   QualType NewFunType =
6405       Ctx.getFunctionType(TT, FPT->getParamTypes(), FPT->getExtProtoInfo());
6406   From->setType(NewFunType);
6407 
6408   CXXMethodDecl *To = Import(From, Lang_CXX14);
6409   EXPECT_TRUE(To);
6410   EXPECT_TRUE(isa<TypedefType>(To->getReturnType()));
6411 }
6412 
6413 TEST_P(ImportAutoFunctions, ReturnWithStructDeclaredInside) {
6414   Decl *FromTU = getTuDecl(
6415       R"(
6416       auto foo() {
6417         struct X {};
6418         return X();
6419       }
6420       )",
6421       Lang_CXX14, "input0.cc");
6422   FunctionDecl *From =
6423       FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
6424 
6425   FunctionDecl *To = Import(From, Lang_CXX14);
6426   EXPECT_TRUE(To);
6427   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6428 }
6429 
6430 TEST_P(ImportAutoFunctions, ReturnWithStructDeclaredInside2) {
6431   Decl *FromTU = getTuDecl(
6432       R"(
6433       auto foo() {
6434         struct X {};
6435         return X();
6436       }
6437       )",
6438       Lang_CXX14, "input0.cc");
6439   FunctionDecl *From =
6440       FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
6441 
6442   // This time import the type directly.
6443   QualType ToT = ImportType(From->getType(), From, Lang_CXX14);
6444   const FunctionProtoType *FPT = cast<FunctionProtoType>(ToT);
6445   EXPECT_TRUE(isa<AutoType>(FPT->getReturnType()));
6446 }
6447 
6448 TEST_P(ImportAutoFunctions, ReturnWithTypedefToStructDeclaredInside) {
6449   Decl *FromTU = getTuDecl(
6450       R"(
6451       auto foo() {
6452         struct X {};
6453         using Y = X;
6454         return Y();
6455       }
6456       )",
6457       Lang_CXX14, "input0.cc");
6458   FunctionDecl *From =
6459       FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
6460 
6461   FunctionDecl *To = Import(From, Lang_CXX14);
6462   EXPECT_TRUE(To);
6463   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6464 }
6465 
6466 TEST_P(ImportAutoFunctions, ReturnWithStructDeclaredNestedInside) {
6467   Decl *FromTU = getTuDecl(
6468       R"(
6469       auto foo() {
6470         struct X { struct Y{}; };
6471         return X::Y();
6472       }
6473       )",
6474       Lang_CXX14, "input0.cc");
6475   FunctionDecl *From =
6476       FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
6477 
6478   FunctionDecl *To = Import(From, Lang_CXX14);
6479   EXPECT_TRUE(To);
6480   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6481 }
6482 
6483 TEST_P(ImportAutoFunctions, ReturnWithInternalLambdaType) {
6484   Decl *FromTU = getTuDecl(
6485       R"(
6486       auto f() {
6487         auto l = []() {
6488           struct X {};
6489           return X();
6490         };
6491         return l();
6492       }
6493       )",
6494       Lang_CXX17, "input0.cc");
6495   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6496       FromTU, functionDecl(hasName("f")));
6497 
6498   FunctionDecl *To = Import(From, Lang_CXX17);
6499   EXPECT_TRUE(To);
6500   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6501 }
6502 
6503 TEST_P(ImportAutoFunctions, ReturnWithTypeInIf) {
6504   Decl *FromTU = getTuDecl(
6505       R"(
6506       auto f() {
6507         if (struct X {} x; true)
6508           return X();
6509         else
6510           return X();
6511       }
6512       )",
6513       Lang_CXX17, "input0.cc");
6514   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6515       FromTU, functionDecl(hasName("f")));
6516 
6517   FunctionDecl *To = Import(From, Lang_CXX17);
6518   EXPECT_TRUE(To);
6519   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6520 }
6521 
6522 TEST_P(ImportAutoFunctions, ReturnWithTypeInFor) {
6523   Decl *FromTU = getTuDecl(
6524       R"(
6525       auto f() {
6526         for (struct X {} x;;)
6527           return X();
6528       }
6529       )",
6530       Lang_CXX17, "input0.cc");
6531   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6532       FromTU, functionDecl(hasName("f")));
6533 
6534   FunctionDecl *To = Import(From, Lang_CXX17);
6535   EXPECT_TRUE(To);
6536   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6537 }
6538 
6539 TEST_P(ImportAutoFunctions, ReturnWithTypeInSwitch) {
6540   Decl *FromTU = getTuDecl(
6541       R"(
6542       auto f() {
6543         switch (struct X {} x; 10) {
6544         case 10:
6545           return X();
6546         }
6547       }
6548       )",
6549       Lang_CXX17, "input0.cc");
6550   FunctionDecl *From = FirstDeclMatcher<FunctionDecl>().match(
6551       FromTU, functionDecl(hasName("f")));
6552 
6553   FunctionDecl *To = Import(From, Lang_CXX17);
6554   EXPECT_TRUE(To);
6555   EXPECT_TRUE(isa<AutoType>(To->getReturnType()));
6556 }
6557 
6558 struct ImportSourceLocations : ASTImporterOptionSpecificTestBase {};
6559 
6560 TEST_P(ImportSourceLocations, PreserveFileIDTreeStructure) {
6561   // Tests that the FileID tree structure (with the links being the include
6562   // chains) is preserved while importing other files (which need to be
6563   // added to this structure with fake include locations.
6564 
6565   SourceLocation Location1;
6566   {
6567     auto Pattern = varDecl(hasName("X"));
6568     Decl *FromTU = getTuDecl("int X;", Lang_C99, "input0.c");
6569     auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
6570 
6571     Location1 = Import(FromD, Lang_C99)->getLocation();
6572   }
6573   SourceLocation Location2;
6574   {
6575     auto Pattern = varDecl(hasName("Y"));
6576     Decl *FromTU = getTuDecl("int Y;", Lang_C99, "input1.c");
6577     auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
6578 
6579     Location2 = Import(FromD, Lang_C99)->getLocation();
6580   }
6581 
6582   SourceManager &ToSM = ToAST->getSourceManager();
6583   FileID FileID1 = ToSM.getFileID(Location1);
6584   FileID FileID2 = ToSM.getFileID(Location2);
6585 
6586   // Check that the imported files look like as if they were included from the
6587   // start of the main file.
6588   SourceLocation FileStart = ToSM.getLocForStartOfFile(ToSM.getMainFileID());
6589   EXPECT_NE(FileID1, ToSM.getMainFileID());
6590   EXPECT_NE(FileID2, ToSM.getMainFileID());
6591   EXPECT_EQ(ToSM.getIncludeLoc(FileID1), FileStart);
6592   EXPECT_EQ(ToSM.getIncludeLoc(FileID2), FileStart);
6593 
6594   // Let the SourceManager check the order of the locations. The order should
6595   // be the order in which the declarations are imported.
6596   EXPECT_TRUE(ToSM.isBeforeInTranslationUnit(Location1, Location2));
6597   EXPECT_FALSE(ToSM.isBeforeInTranslationUnit(Location2, Location1));
6598 }
6599 
6600 TEST_P(ImportSourceLocations, NormalFileBuffer) {
6601   // Test importing normal file buffers.
6602 
6603   std::string Path = "input0.c";
6604   std::string Source = "int X;";
6605   TranslationUnitDecl *FromTU = getTuDecl(Source, Lang_C99, Path);
6606 
6607   SourceLocation ImportedLoc;
6608   {
6609     // Import the VarDecl to trigger the importing of the FileID.
6610     auto Pattern = varDecl(hasName("X"));
6611     VarDecl *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
6612     ImportedLoc = Import(FromD, Lang_C99)->getLocation();
6613   }
6614 
6615   // Make sure the imported buffer has the original contents.
6616   SourceManager &ToSM = ToAST->getSourceManager();
6617   FileID ImportedID = ToSM.getFileID(ImportedLoc);
6618   EXPECT_EQ(Source,
6619             ToSM.getBufferOrFake(ImportedID, SourceLocation()).getBuffer());
6620 }
6621 
6622 TEST_P(ImportSourceLocations, OverwrittenFileBuffer) {
6623   // Test importing overwritten file buffers.
6624 
6625   std::string Path = "input0.c";
6626   TranslationUnitDecl *FromTU = getTuDecl("int X;", Lang_C99, Path);
6627 
6628   // Overwrite the file buffer for our input file with new content.
6629   const std::string Contents = "overwritten contents";
6630   SourceLocation ImportedLoc;
6631   {
6632     SourceManager &FromSM = FromTU->getASTContext().getSourceManager();
6633     clang::FileManager &FM = FromSM.getFileManager();
6634     const clang::FileEntry &FE =
6635         *FM.getVirtualFile(Path, static_cast<off_t>(Contents.size()), 0);
6636 
6637     llvm::SmallVector<char, 64> Buffer;
6638     Buffer.append(Contents.begin(), Contents.end());
6639     auto FileContents = std::make_unique<llvm::SmallVectorMemoryBuffer>(
6640         std::move(Buffer), Path, /*RequiresNullTerminator=*/false);
6641     FromSM.overrideFileContents(&FE, std::move(FileContents));
6642 
6643     // Import the VarDecl to trigger the importing of the FileID.
6644     auto Pattern = varDecl(hasName("X"));
6645     VarDecl *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
6646     ImportedLoc = Import(FromD, Lang_C99)->getLocation();
6647   }
6648 
6649   // Make sure the imported buffer has the overwritten contents.
6650   SourceManager &ToSM = ToAST->getSourceManager();
6651   FileID ImportedID = ToSM.getFileID(ImportedLoc);
6652   EXPECT_EQ(Contents,
6653             ToSM.getBufferOrFake(ImportedID, SourceLocation()).getBuffer());
6654 }
6655 
6656 struct ImportAttributes : public ASTImporterOptionSpecificTestBase {
6657   void checkAttrImportCommon(const Attr *From, const Attr *To,
6658                              const Decl *ToD) {
6659 
6660     // Verify that dump does not crash because invalid data.
6661     ToD->dump(llvm::nulls());
6662 
6663     EXPECT_EQ(From->getParsedKind(), To->getParsedKind());
6664     EXPECT_EQ(From->getSyntax(), To->getSyntax());
6665     if (From->getAttrName()) {
6666       EXPECT_TRUE(To->getAttrName());
6667       EXPECT_STREQ(From->getAttrName()->getNameStart(),
6668                    To->getAttrName()->getNameStart());
6669     } else {
6670       EXPECT_FALSE(To->getAttrName());
6671     }
6672     if (From->getScopeName()) {
6673       EXPECT_TRUE(To->getScopeName());
6674       EXPECT_STREQ(From->getScopeName()->getNameStart(),
6675                    To->getScopeName()->getNameStart());
6676     } else {
6677       EXPECT_FALSE(To->getScopeName());
6678     }
6679     EXPECT_EQ(From->getSpellingListIndex(), To->getSpellingListIndex());
6680     EXPECT_STREQ(From->getSpelling(), To->getSpelling());
6681     EXPECT_EQ(From->isInherited(), To->isInherited());
6682     EXPECT_EQ(From->isImplicit(), To->isImplicit());
6683     EXPECT_EQ(From->isPackExpansion(), To->isPackExpansion());
6684     EXPECT_EQ(From->isLateParsed(), To->isLateParsed());
6685   }
6686 
6687   template <class DT, class AT>
6688   void importAttr(const char *Code, AT *&FromAttr, AT *&ToAttr) {
6689     static_assert(std::is_base_of<Attr, AT>::value, "AT should be an Attr");
6690     static_assert(std::is_base_of<Decl, DT>::value, "DT should be a Decl");
6691 
6692     Decl *FromTU = getTuDecl(Code, Lang_CXX11, "input.cc");
6693     DT *FromD =
6694         FirstDeclMatcher<DT>().match(FromTU, namedDecl(hasName("test")));
6695     ASSERT_TRUE(FromD);
6696 
6697     DT *ToD = Import(FromD, Lang_CXX11);
6698     ASSERT_TRUE(ToD);
6699 
6700     FromAttr = FromD->template getAttr<AT>();
6701     ToAttr = ToD->template getAttr<AT>();
6702     ASSERT_TRUE(FromAttr);
6703     EXPECT_TRUE(ToAttr);
6704 
6705     checkAttrImportCommon(FromAttr, ToAttr, ToD);
6706   }
6707 
6708   template <class T> void checkImported(const T *From, const T *To) {
6709     EXPECT_TRUE(To);
6710     EXPECT_NE(From, To);
6711   }
6712 
6713   template <class T>
6714   void checkImportVariadicArg(const llvm::iterator_range<T **> &From,
6715                               const llvm::iterator_range<T **> &To) {
6716     for (auto FromI = From.begin(), ToI = To.begin(); FromI != From.end();
6717          ++FromI, ++ToI) {
6718       ASSERT_NE(ToI, To.end());
6719       checkImported(*FromI, *ToI);
6720     }
6721   }
6722 };
6723 
6724 template <>
6725 void ImportAttributes::checkImported<Decl>(const Decl *From, const Decl *To) {
6726   EXPECT_TRUE(To);
6727   EXPECT_NE(From, To);
6728   EXPECT_EQ(To->getTranslationUnitDecl(),
6729             ToAST->getASTContext().getTranslationUnitDecl());
6730 }
6731 
6732 // FIXME: Use ImportAttributes for this test.
6733 TEST_P(ASTImporterOptionSpecificTestBase, ImportExprOfAlignmentAttr) {
6734   // Test if import of these packed and aligned attributes does not trigger an
6735   // error situation where source location from 'From' context is referenced in
6736   // 'To' context through evaluation of the alignof attribute.
6737   // This happens if the 'alignof(A)' expression is not imported correctly.
6738   Decl *FromTU = getTuDecl(
6739       R"(
6740       struct __attribute__((packed)) A { int __attribute__((aligned(8))) X; };
6741       struct alignas(alignof(A)) S {};
6742       )",
6743       Lang_CXX11, "input.cc");
6744   auto *FromD = FirstDeclMatcher<CXXRecordDecl>().match(
6745       FromTU, cxxRecordDecl(hasName("S"), unless(isImplicit())));
6746   ASSERT_TRUE(FromD);
6747 
6748   auto *ToD = Import(FromD, Lang_CXX11);
6749   ASSERT_TRUE(ToD);
6750 
6751   auto *FromAttr = FromD->getAttr<AlignedAttr>();
6752   auto *ToAttr = ToD->getAttr<AlignedAttr>();
6753   EXPECT_EQ(FromAttr->isInherited(), ToAttr->isInherited());
6754   EXPECT_EQ(FromAttr->isPackExpansion(), ToAttr->isPackExpansion());
6755   EXPECT_EQ(FromAttr->isImplicit(), ToAttr->isImplicit());
6756   EXPECT_EQ(FromAttr->getSyntax(), ToAttr->getSyntax());
6757   EXPECT_EQ(FromAttr->getSemanticSpelling(), ToAttr->getSemanticSpelling());
6758   EXPECT_TRUE(ToAttr->getAlignmentExpr());
6759 
6760   auto *ToA = FirstDeclMatcher<CXXRecordDecl>().match(
6761       ToD->getTranslationUnitDecl(),
6762       cxxRecordDecl(hasName("A"), unless(isImplicit())));
6763   // Ensure that 'struct A' was imported (through reference from attribute of
6764   // 'S').
6765   EXPECT_TRUE(ToA);
6766 }
6767 
6768 // FIXME: Use ImportAttributes for this test.
6769 TEST_P(ASTImporterOptionSpecificTestBase, ImportFormatAttr) {
6770   Decl *FromTU = getTuDecl(
6771       R"(
6772       int foo(const char * fmt, ...)
6773       __attribute__ ((__format__ (__scanf__, 1, 2)));
6774       )",
6775       Lang_CXX03, "input.cc");
6776   auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
6777       FromTU, functionDecl(hasName("foo")));
6778   ASSERT_TRUE(FromD);
6779 
6780   auto *ToD = Import(FromD, Lang_CXX03);
6781   ASSERT_TRUE(ToD);
6782   ToD->dump(); // Should not crash!
6783 
6784   auto *FromAttr = FromD->getAttr<FormatAttr>();
6785   auto *ToAttr = ToD->getAttr<FormatAttr>();
6786   EXPECT_EQ(FromAttr->isInherited(), ToAttr->isInherited());
6787   EXPECT_EQ(FromAttr->isPackExpansion(), ToAttr->isPackExpansion());
6788   EXPECT_EQ(FromAttr->isImplicit(), ToAttr->isImplicit());
6789   EXPECT_EQ(FromAttr->getSyntax(), ToAttr->getSyntax());
6790   EXPECT_EQ(FromAttr->getAttributeSpellingListIndex(),
6791             ToAttr->getAttributeSpellingListIndex());
6792   EXPECT_EQ(FromAttr->getType()->getName(), ToAttr->getType()->getName());
6793 }
6794 
6795 TEST_P(ImportAttributes, ImportEnableIf) {
6796   EnableIfAttr *FromAttr, *ToAttr;
6797   importAttr<FunctionDecl>(
6798       "void test(int A) __attribute__((enable_if(A == 1, \"message\")));",
6799       FromAttr, ToAttr);
6800   checkImported(FromAttr->getCond(), ToAttr->getCond());
6801   EXPECT_EQ(FromAttr->getMessage(), ToAttr->getMessage());
6802 }
6803 
6804 TEST_P(ImportAttributes, ImportGuardedVar) {
6805   GuardedVarAttr *FromAttr, *ToAttr;
6806   importAttr<VarDecl>("int test __attribute__((guarded_var));", FromAttr,
6807                       ToAttr);
6808 }
6809 
6810 TEST_P(ImportAttributes, ImportPtGuardedVar) {
6811   PtGuardedVarAttr *FromAttr, *ToAttr;
6812   importAttr<VarDecl>("int *test __attribute__((pt_guarded_var));", FromAttr,
6813                       ToAttr);
6814 }
6815 
6816 TEST_P(ImportAttributes, ImportScopedLockable) {
6817   ScopedLockableAttr *FromAttr, *ToAttr;
6818   importAttr<CXXRecordDecl>("struct __attribute__((scoped_lockable)) test {};",
6819                             FromAttr, ToAttr);
6820 }
6821 
6822 TEST_P(ImportAttributes, ImportCapability) {
6823   CapabilityAttr *FromAttr, *ToAttr;
6824   importAttr<CXXRecordDecl>(
6825       "struct __attribute__((capability(\"cap\"))) test {};", FromAttr, ToAttr);
6826   EXPECT_EQ(FromAttr->getName(), ToAttr->getName());
6827 }
6828 
6829 TEST_P(ImportAttributes, ImportAssertCapability) {
6830   AssertCapabilityAttr *FromAttr, *ToAttr;
6831   importAttr<FunctionDecl>(
6832       "void test(int A1, int A2) __attribute__((assert_capability(A1, A2)));",
6833       FromAttr, ToAttr);
6834   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6835 }
6836 
6837 TEST_P(ImportAttributes, ImportAcquireCapability) {
6838   AcquireCapabilityAttr *FromAttr, *ToAttr;
6839   importAttr<FunctionDecl>(
6840       "void test(int A1, int A2) __attribute__((acquire_capability(A1, A2)));",
6841       FromAttr, ToAttr);
6842   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6843 }
6844 
6845 TEST_P(ImportAttributes, ImportTryAcquireCapability) {
6846   TryAcquireCapabilityAttr *FromAttr, *ToAttr;
6847   importAttr<FunctionDecl>(
6848       "void test(int A1, int A2) __attribute__((try_acquire_capability(1, A1, "
6849       "A2)));",
6850       FromAttr, ToAttr);
6851   checkImported(FromAttr->getSuccessValue(), ToAttr->getSuccessValue());
6852   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6853 }
6854 
6855 TEST_P(ImportAttributes, ImportReleaseCapability) {
6856   ReleaseCapabilityAttr *FromAttr, *ToAttr;
6857   importAttr<FunctionDecl>(
6858       "void test(int A1, int A2) __attribute__((release_capability(A1, A2)));",
6859       FromAttr, ToAttr);
6860   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6861 }
6862 
6863 TEST_P(ImportAttributes, ImportRequiresCapability) {
6864   RequiresCapabilityAttr *FromAttr, *ToAttr;
6865   importAttr<FunctionDecl>(
6866       "void test(int A1, int A2) __attribute__((requires_capability(A1, A2)));",
6867       FromAttr, ToAttr);
6868   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6869 }
6870 
6871 TEST_P(ImportAttributes, ImportNoThreadSafetyAnalysis) {
6872   NoThreadSafetyAnalysisAttr *FromAttr, *ToAttr;
6873   importAttr<FunctionDecl>(
6874       "void test() __attribute__((no_thread_safety_analysis));", FromAttr,
6875       ToAttr);
6876 }
6877 
6878 TEST_P(ImportAttributes, ImportGuardedBy) {
6879   GuardedByAttr *FromAttr, *ToAttr;
6880   importAttr<VarDecl>(
6881       R"(
6882       int G;
6883       int test __attribute__((guarded_by(G)));
6884       )",
6885       FromAttr, ToAttr);
6886   checkImported(FromAttr->getArg(), ToAttr->getArg());
6887 }
6888 
6889 TEST_P(ImportAttributes, ImportPtGuardedBy) {
6890   PtGuardedByAttr *FromAttr, *ToAttr;
6891   importAttr<VarDecl>(
6892       R"(
6893       int G;
6894       int *test __attribute__((pt_guarded_by(G)));
6895       )",
6896       FromAttr, ToAttr);
6897   checkImported(FromAttr->getArg(), ToAttr->getArg());
6898 }
6899 
6900 TEST_P(ImportAttributes, ImportAcquiredAfter) {
6901   AcquiredAfterAttr *FromAttr, *ToAttr;
6902   importAttr<VarDecl>(
6903       R"(
6904       struct __attribute__((lockable)) L {};
6905       L A1;
6906       L A2;
6907       L test __attribute__((acquired_after(A1, A2)));
6908       )",
6909       FromAttr, ToAttr);
6910   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6911 }
6912 
6913 TEST_P(ImportAttributes, ImportAcquiredBefore) {
6914   AcquiredBeforeAttr *FromAttr, *ToAttr;
6915   importAttr<VarDecl>(
6916       R"(
6917       struct __attribute__((lockable)) L {};
6918       L A1;
6919       L A2;
6920       L test __attribute__((acquired_before(A1, A2)));
6921       )",
6922       FromAttr, ToAttr);
6923   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6924 }
6925 
6926 TEST_P(ImportAttributes, ImportAssertExclusiveLock) {
6927   AssertExclusiveLockAttr *FromAttr, *ToAttr;
6928   importAttr<FunctionDecl>("void test(int A1, int A2) "
6929                            "__attribute__((assert_exclusive_lock(A1, A2)));",
6930                            FromAttr, ToAttr);
6931   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6932 }
6933 
6934 TEST_P(ImportAttributes, ImportAssertSharedLock) {
6935   AssertSharedLockAttr *FromAttr, *ToAttr;
6936   importAttr<FunctionDecl>(
6937       "void test(int A1, int A2) __attribute__((assert_shared_lock(A1, A2)));",
6938       FromAttr, ToAttr);
6939   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6940 }
6941 
6942 TEST_P(ImportAttributes, ImportExclusiveTrylockFunction) {
6943   ExclusiveTrylockFunctionAttr *FromAttr, *ToAttr;
6944   importAttr<FunctionDecl>(
6945       "void test(int A1, int A2) __attribute__((exclusive_trylock_function(1, "
6946       "A1, A2)));",
6947       FromAttr, ToAttr);
6948   checkImported(FromAttr->getSuccessValue(), ToAttr->getSuccessValue());
6949   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6950 }
6951 
6952 TEST_P(ImportAttributes, ImportSharedTrylockFunction) {
6953   SharedTrylockFunctionAttr *FromAttr, *ToAttr;
6954   importAttr<FunctionDecl>(
6955       "void test(int A1, int A2) __attribute__((shared_trylock_function(1, A1, "
6956       "A2)));",
6957       FromAttr, ToAttr);
6958   checkImported(FromAttr->getSuccessValue(), ToAttr->getSuccessValue());
6959   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6960 }
6961 
6962 TEST_P(ImportAttributes, ImportLockReturned) {
6963   LockReturnedAttr *FromAttr, *ToAttr;
6964   importAttr<FunctionDecl>(
6965       "void test(int A1) __attribute__((lock_returned(A1)));", FromAttr,
6966       ToAttr);
6967   checkImported(FromAttr->getArg(), ToAttr->getArg());
6968 }
6969 
6970 TEST_P(ImportAttributes, ImportLocksExcluded) {
6971   LocksExcludedAttr *FromAttr, *ToAttr;
6972   importAttr<FunctionDecl>(
6973       "void test(int A1, int A2) __attribute__((locks_excluded(A1, A2)));",
6974       FromAttr, ToAttr);
6975   checkImportVariadicArg(FromAttr->args(), ToAttr->args());
6976 }
6977 
6978 template <typename T>
6979 auto ExtendWithOptions(const T &Values, const std::vector<std::string> &Args) {
6980   auto Copy = Values;
6981   for (std::vector<std::string> &ArgV : Copy) {
6982     for (const std::string &Arg : Args) {
6983       ArgV.push_back(Arg);
6984     }
6985   }
6986   return ::testing::ValuesIn(Copy);
6987 }
6988 
6989 struct ImportWithExternalSource : ASTImporterOptionSpecificTestBase {
6990   ImportWithExternalSource() {
6991     Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
6992                  ASTContext &FromContext, FileManager &FromFileManager,
6993                  bool MinimalImport,
6994                  const std::shared_ptr<ASTImporterSharedState> &SharedState) {
6995       return new ASTImporter(ToContext, ToFileManager, FromContext,
6996                              // Use minimal import for these tests.
6997                              FromFileManager, /*MinimalImport=*/true,
6998                              // We use the regular lookup.
6999                              /*SharedState=*/nullptr);
7000     };
7001   }
7002 };
7003 
7004 /// An ExternalASTSource that keeps track of the tags is completed.
7005 struct SourceWithCompletedTagList : clang::ExternalASTSource {
7006   std::vector<clang::TagDecl *> &CompletedTags;
7007   SourceWithCompletedTagList(std::vector<clang::TagDecl *> &CompletedTags)
7008       : CompletedTags(CompletedTags) {}
7009   void CompleteType(TagDecl *Tag) override {
7010     auto *Record = cast<CXXRecordDecl>(Tag);
7011     Record->startDefinition();
7012     Record->completeDefinition();
7013     CompletedTags.push_back(Tag);
7014   }
7015   using clang::ExternalASTSource::CompleteType;
7016 };
7017 
7018 TEST_P(ImportWithExternalSource, CompleteRecordBeforeImporting) {
7019   // Create an empty TU.
7020   TranslationUnitDecl *FromTU = getTuDecl("", Lang_CXX03, "input.cpp");
7021 
7022   // Create and add the test ExternalASTSource.
7023   std::vector<clang::TagDecl *> CompletedTags;
7024   IntrusiveRefCntPtr<ExternalASTSource> source =
7025       new SourceWithCompletedTagList(CompletedTags);
7026   clang::ASTContext &Context = FromTU->getASTContext();
7027   Context.setExternalSource(std::move(source));
7028 
7029   // Create a dummy class by hand with external lexical storage.
7030   IdentifierInfo &Ident = Context.Idents.get("test_class");
7031   auto *Record = CXXRecordDecl::Create(
7032       Context, TTK_Class, FromTU, SourceLocation(), SourceLocation(), &Ident);
7033   Record->setHasExternalLexicalStorage();
7034   FromTU->addDecl(Record);
7035 
7036   // Do a minimal import of the created class.
7037   EXPECT_EQ(0U, CompletedTags.size());
7038   Import(Record, Lang_CXX03);
7039   EXPECT_EQ(0U, CompletedTags.size());
7040 
7041   // Import the definition of the created class.
7042   llvm::Error Err = findFromTU(Record)->Importer->ImportDefinition(Record);
7043   EXPECT_FALSE((bool)Err);
7044   consumeError(std::move(Err));
7045 
7046   // Make sure the class was completed once.
7047   EXPECT_EQ(1U, CompletedTags.size());
7048   EXPECT_EQ(Record, CompletedTags.front());
7049 }
7050 
7051 TEST_P(ImportFunctions, CTADImplicit) {
7052   Decl *FromTU = getTuDecl(
7053       R"(
7054       template <typename T> struct A {
7055         A(T);
7056       };
7057       A a{(int)0};
7058       )",
7059       Lang_CXX17, "input.cc");
7060   auto *FromD = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7061       FromTU,
7062       cxxDeductionGuideDecl(hasParameter(0, hasType(asString("A<T>")))));
7063   auto *ToD = Import(FromD, Lang_CXX17);
7064   ASSERT_TRUE(ToD);
7065   EXPECT_TRUE(ToD->isCopyDeductionCandidate());
7066   // Check that the deduced class template is also imported.
7067   EXPECT_TRUE(findFromTU(FromD)->Importer->GetAlreadyImportedOrNull(
7068       FromD->getDeducedTemplate()));
7069 }
7070 
7071 TEST_P(ImportFunctions, CTADUserDefinedExplicit) {
7072   Decl *FromTU = getTuDecl(
7073       R"(
7074       template <typename T> struct A {
7075         A(T);
7076       };
7077       template <typename T> explicit A(T) -> A<float>;
7078       A a{(int)0}; // calls A<float>::A(float)
7079       )",
7080       Lang_CXX17, "input.cc");
7081   auto *FromD = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7082       FromTU, cxxDeductionGuideDecl(unless(isImplicit())));
7083   // Not-implicit: i.e. not compiler-generated, user defined.
7084   ASSERT_FALSE(FromD->isImplicit());
7085   ASSERT_TRUE(FromD->isExplicit()); // Has the explicit keyword.
7086   auto *ToD = Import(FromD, Lang_CXX17);
7087   ASSERT_TRUE(ToD);
7088   EXPECT_FALSE(FromD->isImplicit());
7089   EXPECT_TRUE(ToD->isExplicit());
7090 }
7091 
7092 TEST_P(ImportFunctions, CTADWithLocalTypedef) {
7093   Decl *TU = getTuDecl(
7094       R"(
7095       template <typename T> struct A {
7096         typedef T U;
7097         A(U);
7098       };
7099       A a{(int)0};
7100       )",
7101       Lang_CXX17, "input.cc");
7102   auto *FromD = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7103       TU, cxxDeductionGuideDecl());
7104   auto *ToD = Import(FromD, Lang_CXX17);
7105   ASSERT_TRUE(ToD);
7106 }
7107 
7108 TEST_P(ImportFunctions, ParmVarDeclDeclContext) {
7109   constexpr auto FromTUCode = R"(
7110       void f(int P);
7111       )";
7112   Decl *FromTU = getTuDecl(FromTUCode, Lang_CXX11);
7113   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
7114       FromTU, functionDecl(hasName("f")));
7115   ASSERT_TRUE(FromF);
7116 
7117   auto *ImportedF = Import(FromF, Lang_CXX11);
7118   EXPECT_TRUE(ImportedF);
7119   EXPECT_TRUE(SharedStatePtr->getLookupTable()->contains(
7120       ImportedF, ImportedF->getParamDecl(0)));
7121 }
7122 
7123 // FIXME Move these tests out of ASTImporterTest. For that we need to factor
7124 // out the ASTImporter specific pars from ASTImporterOptionSpecificTestBase
7125 // into a new test Fixture. Then we should lift up this Fixture to its own
7126 // implementation file and only then could we reuse the Fixture in other AST
7127 // unitttests.
7128 struct CTAD : ASTImporterOptionSpecificTestBase {};
7129 
7130 TEST_P(CTAD, DeductionGuideShouldReferToANonLocalTypedef) {
7131   Decl *TU = getTuDecl(
7132       R"(
7133       typedef int U;
7134       template <typename T> struct A {
7135         A(U, T);
7136       };
7137       A a{(int)0, (int)0};
7138       )",
7139       Lang_CXX17, "input.cc");
7140   auto *Guide = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7141       TU, cxxDeductionGuideDecl());
7142   auto *Typedef = FirstDeclMatcher<TypedefNameDecl>().match(
7143       TU, typedefNameDecl(hasName("U")));
7144   ParmVarDecl *Param = Guide->getParamDecl(0);
7145   // The type of the first param (which is a typedef) should match the typedef
7146   // in the global scope.
7147   EXPECT_EQ(Param->getType()->castAs<TypedefType>()->getDecl(), Typedef);
7148 }
7149 
7150 TEST_P(CTAD, DeductionGuideShouldReferToANonLocalTypedefInParamPtr) {
7151   Decl *TU = getTuDecl(
7152       R"(
7153       typedef int U;
7154       template <typename T> struct A {
7155         A(U*, T);
7156       };
7157       A a{(int*)0, (int)0};
7158       )",
7159       Lang_CXX17, "input.cc");
7160   auto *Guide = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7161       TU, cxxDeductionGuideDecl());
7162   auto *Typedef = FirstDeclMatcher<TypedefNameDecl>().match(
7163       TU, typedefNameDecl(hasName("U")));
7164   ParmVarDecl *Param = Guide->getParamDecl(0);
7165   EXPECT_EQ(Param->getType()
7166                 ->getAs<PointerType>()
7167                 ->getPointeeType()
7168                 ->getAs<TypedefType>()
7169                 ->getDecl(),
7170             Typedef);
7171 }
7172 
7173 TEST_P(CTAD, DeductionGuideShouldCopyALocalTypedef) {
7174   Decl *TU = getTuDecl(
7175       R"(
7176       template <typename T> struct A {
7177         typedef T U;
7178         A(U, T);
7179       };
7180       A a{(int)0, (int)0};
7181       )",
7182       Lang_CXX17, "input.cc");
7183   auto *Guide = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7184       TU, cxxDeductionGuideDecl());
7185   auto *Typedef = FirstDeclMatcher<TypedefNameDecl>().match(
7186       TU, typedefNameDecl(hasName("U")));
7187   ParmVarDecl *Param = Guide->getParamDecl(0);
7188   EXPECT_NE(Param->getType()->castAs<TypedefType>()->getDecl(), Typedef);
7189 }
7190 
7191 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, CTAD,
7192                          DefaultTestValuesForRunOptions);
7193 
7194 TEST_P(ASTImporterOptionSpecificTestBase, TypedefWithAttribute) {
7195   Decl *TU = getTuDecl(
7196       R"(
7197       namespace N {
7198         typedef int X __attribute__((annotate("A")));
7199       }
7200       )",
7201       Lang_CXX17, "input.cc");
7202   auto *FromD =
7203       FirstDeclMatcher<TypedefDecl>().match(TU, typedefDecl(hasName("X")));
7204   auto *ToD = Import(FromD, Lang_CXX17);
7205   ASSERT_TRUE(ToD);
7206   ASSERT_EQ(ToD->getAttrs().size(), 1U);
7207   auto *ToAttr = dyn_cast<AnnotateAttr>(ToD->getAttrs()[0]);
7208   ASSERT_TRUE(ToAttr);
7209   EXPECT_EQ(ToAttr->getAnnotation(), "A");
7210 }
7211 
7212 TEST_P(ASTImporterOptionSpecificTestBase,
7213        ImportOfTemplatedDeclWhenPreviousDeclHasNoDescribedTemplateSet) {
7214   Decl *FromTU = getTuDecl(
7215       R"(
7216 
7217       namespace std {
7218         template<typename T>
7219         class basic_stringbuf;
7220       }
7221       namespace std {
7222         class char_traits;
7223         template<typename T = char_traits>
7224         class basic_stringbuf;
7225       }
7226       namespace std {
7227         template<typename T>
7228         class basic_stringbuf {};
7229       }
7230 
7231       )",
7232       Lang_CXX11);
7233 
7234   auto *From1 = FirstDeclMatcher<ClassTemplateDecl>().match(
7235       FromTU,
7236       classTemplateDecl(hasName("basic_stringbuf"), unless(isImplicit())));
7237   auto *To1 = cast_or_null<ClassTemplateDecl>(Import(From1, Lang_CXX11));
7238   EXPECT_TRUE(To1);
7239 
7240   auto *From2 = LastDeclMatcher<ClassTemplateDecl>().match(
7241       FromTU,
7242       classTemplateDecl(hasName("basic_stringbuf"), unless(isImplicit())));
7243   auto *To2 = cast_or_null<ClassTemplateDecl>(Import(From2, Lang_CXX11));
7244   EXPECT_TRUE(To2);
7245 }
7246 
7247 TEST_P(ASTImporterOptionSpecificTestBase, ImportOfCapturedVLAType) {
7248   Decl *FromTU = getTuDecl(
7249       R"(
7250       void declToImport(int N) {
7251         int VLA[N];
7252         [&VLA] {}; // FieldDecl inside the lambda.
7253       }
7254       )",
7255       Lang_CXX14);
7256   auto *FromFD = FirstDeclMatcher<FieldDecl>().match(FromTU, fieldDecl());
7257   ASSERT_TRUE(FromFD);
7258   ASSERT_TRUE(FromFD->hasCapturedVLAType());
7259 
7260   auto *ToFD = Import(FromFD, Lang_CXX14);
7261   EXPECT_TRUE(ToFD);
7262   EXPECT_TRUE(ToFD->hasCapturedVLAType());
7263   EXPECT_NE(FromFD->getCapturedVLAType(), ToFD->getCapturedVLAType());
7264 }
7265 
7266 TEST_P(ASTImporterOptionSpecificTestBase, ImportEnumMemberSpecialization) {
7267   Decl *FromTU = getTuDecl(
7268       R"(
7269       template <class T> struct A {
7270         enum tagname { enumerator };
7271       };
7272       template struct A<int>;
7273       )",
7274       Lang_CXX03);
7275   auto *FromD = FirstDeclMatcher<EnumDecl>().match(
7276       FromTU, enumDecl(hasName("tagname"),
7277                        hasParent(classTemplateSpecializationDecl())));
7278   ASSERT_TRUE(FromD);
7279   ASSERT_TRUE(FromD->getMemberSpecializationInfo());
7280 
7281   auto *ToD = Import(FromD, Lang_CXX03);
7282   EXPECT_TRUE(ToD);
7283   EXPECT_TRUE(ToD->getMemberSpecializationInfo());
7284   EXPECT_EQ(FromD->getTemplateSpecializationKind(),
7285             ToD->getTemplateSpecializationKind());
7286 }
7287 
7288 TEST_P(ASTImporterOptionSpecificTestBase, ImportIsInheritingConstructorBit) {
7289   Decl *FromTU = getTuDecl(
7290       R"(
7291       struct A {
7292         A(int);
7293       };
7294       struct B : A {
7295         using A::A; // Inherited ctor.
7296       };
7297       void f() {
7298         (B(0));
7299       }
7300       )",
7301       Lang_CXX11);
7302   auto *FromD = FirstDeclMatcher<CXXConstructorDecl>().match(
7303       FromTU, cxxConstructorDecl(isInheritingConstructor()));
7304   ASSERT_TRUE(FromD);
7305   ASSERT_TRUE(FromD->isInheritingConstructor());
7306 
7307   auto *ToD = Import(FromD, Lang_CXX11);
7308   ASSERT_TRUE(ToD);
7309   EXPECT_TRUE(ToD->isInheritingConstructor());
7310 }
7311 
7312 TEST_P(ASTImporterOptionSpecificTestBase, ImportConstructorUsingShadow) {
7313   TranslationUnitDecl *FromTU = getTuDecl(
7314       R"(
7315       struct A {
7316         A(int, int);
7317       };
7318       struct B : A {
7319         using A::A;
7320       };
7321       struct C : B {
7322         using B::B;
7323       };
7324       )",
7325       Lang_CXX11);
7326 
7327   auto CheckAST = [](TranslationUnitDecl *TU, CXXRecordDecl *RecordC) {
7328     auto *RecordA = FirstDeclMatcher<CXXRecordDecl>().match(
7329         TU, cxxRecordDecl(hasName("A")));
7330     auto *RecordB = FirstDeclMatcher<CXXRecordDecl>().match(
7331         TU, cxxRecordDecl(hasName("B")));
7332     auto *ConstrA = FirstDeclMatcher<CXXConstructorDecl>().match(
7333         TU, cxxConstructorDecl(hasParent(equalsNode(RecordA)),
7334                                parameterCountIs(2)));
7335     auto *ShadowBA = cast<ConstructorUsingShadowDecl>(
7336         FirstDeclMatcher<UsingShadowDecl>().match(
7337             TU, usingShadowDecl(hasParent(equalsNode(RecordB)),
7338                                 hasTargetDecl(equalsNode(ConstrA)))));
7339     auto *ShadowCA = cast<ConstructorUsingShadowDecl>(
7340         FirstDeclMatcher<UsingShadowDecl>().match(
7341             TU, usingShadowDecl(hasParent(equalsNode(RecordC)),
7342                                 hasTargetDecl(equalsNode(ConstrA)))));
7343     EXPECT_EQ(ShadowBA->getTargetDecl(), ConstrA);
7344     EXPECT_EQ(ShadowBA->getNominatedBaseClass(), RecordA);
7345     EXPECT_EQ(ShadowBA->getConstructedBaseClass(), RecordA);
7346     EXPECT_EQ(ShadowBA->getNominatedBaseClassShadowDecl(), nullptr);
7347     EXPECT_EQ(ShadowBA->getConstructedBaseClassShadowDecl(), nullptr);
7348     EXPECT_FALSE(ShadowBA->constructsVirtualBase());
7349     EXPECT_EQ(ShadowCA->getTargetDecl(), ConstrA);
7350     EXPECT_EQ(ShadowCA->getNominatedBaseClass(), RecordB);
7351     EXPECT_EQ(ShadowCA->getConstructedBaseClass(), RecordB);
7352     EXPECT_EQ(ShadowCA->getNominatedBaseClassShadowDecl(), ShadowBA);
7353     EXPECT_EQ(ShadowCA->getConstructedBaseClassShadowDecl(), ShadowBA);
7354     EXPECT_FALSE(ShadowCA->constructsVirtualBase());
7355   };
7356 
7357   auto *FromC = FirstDeclMatcher<CXXRecordDecl>().match(
7358       FromTU, cxxRecordDecl(hasName("C")));
7359 
7360   auto *ToC = Import(FromC, Lang_CXX11);
7361   TranslationUnitDecl *ToTU = ToC->getTranslationUnitDecl();
7362 
7363   CheckAST(FromTU, FromC);
7364   CheckAST(ToTU, ToC);
7365 }
7366 
7367 AST_MATCHER_P(UsingShadowDecl, hasIntroducerDecl, internal::Matcher<NamedDecl>,
7368               InnerMatcher) {
7369   return InnerMatcher.matches(*Node.getIntroducer(), Finder, Builder);
7370 }
7371 
7372 TEST_P(ASTImporterOptionSpecificTestBase,
7373        ImportConstructorUsingShadowVirtualBase) {
7374   TranslationUnitDecl *FromTU = getTuDecl(
7375       R"(
7376       struct A { A(int, int); };
7377       struct B : A { using A::A; };
7378 
7379       struct V1 : virtual B { using B::B; };
7380       struct V2 : virtual B { using B::B; };
7381 
7382       struct D2 : V1, V2 {
7383         using V1::V1;
7384         using V2::V2;
7385       };
7386       )",
7387       Lang_CXX11);
7388 
7389   auto CheckAST = [](TranslationUnitDecl *TU, CXXRecordDecl *RecordD2) {
7390     auto *RecordA = FirstDeclMatcher<CXXRecordDecl>().match(
7391         TU, cxxRecordDecl(hasName("A")));
7392     auto *RecordB = FirstDeclMatcher<CXXRecordDecl>().match(
7393         TU, cxxRecordDecl(hasName("B")));
7394     auto *RecordV1 = FirstDeclMatcher<CXXRecordDecl>().match(
7395         TU, cxxRecordDecl(hasName("V1")));
7396     auto *RecordV2 = FirstDeclMatcher<CXXRecordDecl>().match(
7397         TU, cxxRecordDecl(hasName("V2")));
7398     auto *ConstrA = FirstDeclMatcher<CXXConstructorDecl>().match(
7399         TU, cxxConstructorDecl(hasParent(equalsNode(RecordA)),
7400                                parameterCountIs(2)));
7401     auto *ConstrB = FirstDeclMatcher<CXXConstructorDecl>().match(
7402         TU, cxxConstructorDecl(hasParent(equalsNode(RecordB)),
7403                                isCopyConstructor()));
7404     auto *UsingD2V1 = FirstDeclMatcher<UsingDecl>().match(
7405         TU, usingDecl(hasParent(equalsNode(RecordD2))));
7406     auto *UsingD2V2 = LastDeclMatcher<UsingDecl>().match(
7407         TU, usingDecl(hasParent(equalsNode(RecordD2))));
7408     auto *ShadowBA = cast<ConstructorUsingShadowDecl>(
7409         FirstDeclMatcher<UsingShadowDecl>().match(
7410             TU, usingShadowDecl(hasParent(equalsNode(RecordB)),
7411                                 hasTargetDecl(equalsNode(ConstrA)))));
7412     auto *ShadowV1A = cast<ConstructorUsingShadowDecl>(
7413         FirstDeclMatcher<UsingShadowDecl>().match(
7414             TU, usingShadowDecl(hasParent(equalsNode(RecordV1)),
7415                                 hasTargetDecl(equalsNode(ConstrA)))));
7416     auto *ShadowV1B = cast<ConstructorUsingShadowDecl>(
7417         FirstDeclMatcher<UsingShadowDecl>().match(
7418             TU, usingShadowDecl(hasParent(equalsNode(RecordV1)),
7419                                 hasTargetDecl(equalsNode(ConstrB)))));
7420     auto *ShadowV2A = cast<ConstructorUsingShadowDecl>(
7421         FirstDeclMatcher<UsingShadowDecl>().match(
7422             TU, usingShadowDecl(hasParent(equalsNode(RecordV2)),
7423                                 hasTargetDecl(equalsNode(ConstrA)))));
7424     auto *ShadowV2B = cast<ConstructorUsingShadowDecl>(
7425         FirstDeclMatcher<UsingShadowDecl>().match(
7426             TU, usingShadowDecl(hasParent(equalsNode(RecordV2)),
7427                                 hasTargetDecl(equalsNode(ConstrB)))));
7428     auto *ShadowD2V1A = cast<ConstructorUsingShadowDecl>(
7429         FirstDeclMatcher<UsingShadowDecl>().match(
7430             TU, usingShadowDecl(hasParent(equalsNode(RecordD2)),
7431                                 hasIntroducerDecl(equalsNode(UsingD2V1)),
7432                                 hasTargetDecl(equalsNode(ConstrA)))));
7433     auto *ShadowD2V1B = cast<ConstructorUsingShadowDecl>(
7434         FirstDeclMatcher<UsingShadowDecl>().match(
7435             TU, usingShadowDecl(hasParent(equalsNode(RecordD2)),
7436                                 hasIntroducerDecl(equalsNode(UsingD2V1)),
7437                                 hasTargetDecl(equalsNode(ConstrB)))));
7438     auto *ShadowD2V2A = cast<ConstructorUsingShadowDecl>(
7439         FirstDeclMatcher<UsingShadowDecl>().match(
7440             TU, usingShadowDecl(hasParent(equalsNode(RecordD2)),
7441                                 hasIntroducerDecl(equalsNode(UsingD2V2)),
7442                                 hasTargetDecl(equalsNode(ConstrA)))));
7443     auto *ShadowD2V2B = cast<ConstructorUsingShadowDecl>(
7444         FirstDeclMatcher<UsingShadowDecl>().match(
7445             TU, usingShadowDecl(hasParent(equalsNode(RecordD2)),
7446                                 hasIntroducerDecl(equalsNode(UsingD2V2)),
7447                                 hasTargetDecl(equalsNode(ConstrB)))));
7448 
7449     EXPECT_EQ(ShadowD2V1A->getTargetDecl(), ConstrA);
7450     EXPECT_EQ(ShadowD2V1A->getNominatedBaseClassShadowDecl(), ShadowV1A);
7451     EXPECT_EQ(ShadowD2V1A->getNominatedBaseClass(), RecordV1);
7452     EXPECT_EQ(ShadowD2V1A->getConstructedBaseClassShadowDecl(), ShadowBA);
7453     EXPECT_EQ(ShadowD2V1A->getConstructedBaseClass(), RecordB);
7454     EXPECT_TRUE(ShadowD2V1A->constructsVirtualBase());
7455     EXPECT_EQ(ShadowD2V1B->getTargetDecl(), ConstrB);
7456     EXPECT_EQ(ShadowD2V1B->getNominatedBaseClassShadowDecl(), ShadowV1B);
7457     EXPECT_EQ(ShadowD2V1B->getNominatedBaseClass(), RecordV1);
7458     EXPECT_EQ(ShadowD2V1B->getConstructedBaseClassShadowDecl(), nullptr);
7459     EXPECT_EQ(ShadowD2V1B->getConstructedBaseClass(), RecordB);
7460     EXPECT_TRUE(ShadowD2V1B->constructsVirtualBase());
7461     EXPECT_EQ(ShadowD2V2A->getTargetDecl(), ConstrA);
7462     EXPECT_EQ(ShadowD2V2A->getNominatedBaseClassShadowDecl(), ShadowV2A);
7463     EXPECT_EQ(ShadowD2V2A->getNominatedBaseClass(), RecordV2);
7464     EXPECT_EQ(ShadowD2V2A->getConstructedBaseClassShadowDecl(), ShadowBA);
7465     EXPECT_EQ(ShadowD2V2A->getConstructedBaseClass(), RecordB);
7466     EXPECT_TRUE(ShadowD2V2A->constructsVirtualBase());
7467     EXPECT_EQ(ShadowD2V2B->getTargetDecl(), ConstrB);
7468     EXPECT_EQ(ShadowD2V2B->getNominatedBaseClassShadowDecl(), ShadowV2B);
7469     EXPECT_EQ(ShadowD2V2B->getNominatedBaseClass(), RecordV2);
7470     EXPECT_EQ(ShadowD2V2B->getConstructedBaseClassShadowDecl(), nullptr);
7471     EXPECT_EQ(ShadowD2V2B->getConstructedBaseClass(), RecordB);
7472     EXPECT_TRUE(ShadowD2V2B->constructsVirtualBase());
7473 
7474     EXPECT_TRUE(ShadowV1A->constructsVirtualBase());
7475     EXPECT_TRUE(ShadowV1B->constructsVirtualBase());
7476     EXPECT_TRUE(ShadowV2A->constructsVirtualBase());
7477     EXPECT_TRUE(ShadowV2B->constructsVirtualBase());
7478     EXPECT_FALSE(ShadowBA->constructsVirtualBase());
7479   };
7480 
7481   auto *FromD2 = FirstDeclMatcher<CXXRecordDecl>().match(
7482       FromTU, cxxRecordDecl(hasName("D2")));
7483 
7484   auto *ToD2 = Import(FromD2, Lang_CXX11);
7485   TranslationUnitDecl *ToTU = ToD2->getTranslationUnitDecl();
7486 
7487   CheckAST(FromTU, FromD2);
7488   CheckAST(ToTU, ToD2);
7489 }
7490 
7491 TEST_P(ASTImporterOptionSpecificTestBase, ImportUsingShadowList) {
7492   TranslationUnitDecl *FromTU = getTuDecl(
7493       R"(
7494       struct A {
7495         void f();
7496         void f(int);
7497       };
7498       struct B : A {
7499         using A::f;
7500       };
7501       )",
7502       Lang_CXX11);
7503 
7504   auto *FromB = FirstDeclMatcher<CXXRecordDecl>().match(
7505       FromTU, cxxRecordDecl(hasName("B")));
7506 
7507   auto *ToB = Import(FromB, Lang_CXX11);
7508   TranslationUnitDecl *ToTU = ToB->getTranslationUnitDecl();
7509 
7510   auto *ToUsing = FirstDeclMatcher<UsingDecl>().match(
7511       ToTU, usingDecl(hasParent(equalsNode(ToB))));
7512   auto *ToUsingShadowF1 = FirstDeclMatcher<UsingShadowDecl>().match(
7513       ToTU, usingShadowDecl(hasTargetDecl(
7514                 functionDecl(hasName("f"), parameterCountIs(0)))));
7515   auto *ToUsingShadowF2 = FirstDeclMatcher<UsingShadowDecl>().match(
7516       ToTU, usingShadowDecl(hasTargetDecl(
7517                 functionDecl(hasName("f"), parameterCountIs(1)))));
7518 
7519   EXPECT_EQ(ToUsing->shadow_size(), 2u);
7520   auto ShadowI = ToUsing->shadow_begin();
7521   EXPECT_EQ(*ShadowI, ToUsingShadowF1);
7522   ++ShadowI;
7523   EXPECT_EQ(*ShadowI, ToUsingShadowF2);
7524 }
7525 
7526 AST_MATCHER_P(FunctionTemplateDecl, templateParameterCountIs, unsigned, Cnt) {
7527   return Node.getTemplateParameters()->size() == Cnt;
7528 }
7529 
7530 TEST_P(ASTImporterOptionSpecificTestBase, ImportDeductionGuide) {
7531   TranslationUnitDecl *FromTU = getTuDecl(
7532       R"(
7533       template<class> class A { };
7534       template<class T> class B {
7535           template<class T1, typename = A<T>> B(T1);
7536       };
7537       template<class T>
7538       B(T, T) -> B<int>;
7539       )",
7540       Lang_CXX17);
7541 
7542   // Get the implicit deduction guide for (non-default) constructor of 'B'.
7543   auto *FromDGCtor = FirstDeclMatcher<FunctionTemplateDecl>().match(
7544       FromTU, functionTemplateDecl(templateParameterCountIs(3)));
7545   // Implicit deduction guide for copy constructor of 'B'.
7546   auto *FromDGCopyCtor = FirstDeclMatcher<FunctionTemplateDecl>().match(
7547       FromTU, functionTemplateDecl(templateParameterCountIs(1), isImplicit()));
7548   // User defined deduction guide.
7549   auto *FromDGOther = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7550       FromTU, cxxDeductionGuideDecl(unless(isImplicit())));
7551 
7552   TemplateParameterList *FromDGCtorTP = FromDGCtor->getTemplateParameters();
7553   // Don't know why exactly but this is the DeclContext here.
7554   EXPECT_EQ(FromDGCtorTP->getParam(0)->getDeclContext(),
7555             FromDGCopyCtor->getTemplatedDecl());
7556   EXPECT_EQ(FromDGCtorTP->getParam(1)->getDeclContext(),
7557             FromDGCtor->getTemplatedDecl());
7558   EXPECT_EQ(FromDGCtorTP->getParam(2)->getDeclContext(),
7559             FromDGCtor->getTemplatedDecl());
7560   EXPECT_EQ(
7561       FromDGCopyCtor->getTemplateParameters()->getParam(0)->getDeclContext(),
7562       FromDGCopyCtor->getTemplatedDecl());
7563   EXPECT_EQ(FromDGOther->getDescribedTemplate()
7564                 ->getTemplateParameters()
7565                 ->getParam(0)
7566                 ->getDeclContext(),
7567             FromDGOther);
7568 
7569   auto *ToDGCtor = Import(FromDGCtor, Lang_CXX17);
7570   auto *ToDGCopyCtor = Import(FromDGCopyCtor, Lang_CXX17);
7571   auto *ToDGOther = Import(FromDGOther, Lang_CXX17);
7572   ASSERT_TRUE(ToDGCtor);
7573   ASSERT_TRUE(ToDGCopyCtor);
7574   ASSERT_TRUE(ToDGOther);
7575 
7576   TemplateParameterList *ToDGCtorTP = ToDGCtor->getTemplateParameters();
7577   EXPECT_EQ(ToDGCtorTP->getParam(0)->getDeclContext(),
7578             ToDGCopyCtor->getTemplatedDecl());
7579   EXPECT_EQ(ToDGCtorTP->getParam(1)->getDeclContext(),
7580             ToDGCtor->getTemplatedDecl());
7581   EXPECT_EQ(ToDGCtorTP->getParam(2)->getDeclContext(),
7582             ToDGCtor->getTemplatedDecl());
7583   EXPECT_EQ(
7584       ToDGCopyCtor->getTemplateParameters()->getParam(0)->getDeclContext(),
7585       ToDGCopyCtor->getTemplatedDecl());
7586   EXPECT_EQ(ToDGOther->getDescribedTemplate()
7587                 ->getTemplateParameters()
7588                 ->getParam(0)
7589                 ->getDeclContext(),
7590             ToDGOther);
7591 }
7592 
7593 TEST_P(ASTImporterOptionSpecificTestBase, ImportDeductionGuideDifferentOrder) {
7594   // This test demonstrates that the DeclContext of the imported object is
7595   // dependent on the order of import. The test is an exact copy of the previous
7596   // one except at the indicated locations.
7597   TranslationUnitDecl *FromTU = getTuDecl(
7598       R"(
7599       template<class> class A { };
7600       template<class T> class B {
7601           template<class T1, typename = A<T>> B(T1);
7602       };
7603       template<class T>
7604       B(T, T) -> B<int>;
7605       )",
7606       Lang_CXX17);
7607 
7608   // Get the implicit deduction guide for (non-default) constructor of 'B'.
7609   auto *FromDGCtor = FirstDeclMatcher<FunctionTemplateDecl>().match(
7610       FromTU, functionTemplateDecl(templateParameterCountIs(3)));
7611   // Implicit deduction guide for copy constructor of 'B'.
7612   auto *FromDGCopyCtor = FirstDeclMatcher<FunctionTemplateDecl>().match(
7613       FromTU, functionTemplateDecl(templateParameterCountIs(1), isImplicit()));
7614   // User defined deduction guide.
7615   auto *FromDGOther = FirstDeclMatcher<CXXDeductionGuideDecl>().match(
7616       FromTU, cxxDeductionGuideDecl(unless(isImplicit())));
7617 
7618   TemplateParameterList *FromDGCtorTP = FromDGCtor->getTemplateParameters();
7619   // Don't know why exactly but this is the DeclContext here.
7620   EXPECT_EQ(FromDGCtorTP->getParam(0)->getDeclContext(),
7621             FromDGCopyCtor->getTemplatedDecl());
7622   EXPECT_EQ(FromDGCtorTP->getParam(1)->getDeclContext(),
7623             FromDGCtor->getTemplatedDecl());
7624   EXPECT_EQ(FromDGCtorTP->getParam(2)->getDeclContext(),
7625             FromDGCtor->getTemplatedDecl());
7626   EXPECT_EQ(
7627       FromDGCopyCtor->getTemplateParameters()->getParam(0)->getDeclContext(),
7628       FromDGCopyCtor->getTemplatedDecl());
7629   EXPECT_EQ(FromDGOther->getDescribedTemplate()
7630                 ->getTemplateParameters()
7631                 ->getParam(0)
7632                 ->getDeclContext(),
7633             FromDGOther);
7634 
7635   // Here the import of 'ToDGCopyCtor' and 'ToDGCtor' is reversed relative to
7636   // the previous test.
7637   auto *ToDGCopyCtor = Import(FromDGCopyCtor, Lang_CXX17);
7638   auto *ToDGCtor = Import(FromDGCtor, Lang_CXX17);
7639   auto *ToDGOther = Import(FromDGOther, Lang_CXX17);
7640   ASSERT_TRUE(ToDGCtor);
7641   ASSERT_TRUE(ToDGCopyCtor);
7642   ASSERT_TRUE(ToDGOther);
7643 
7644   TemplateParameterList *ToDGCtorTP = ToDGCtor->getTemplateParameters();
7645   // Next line: DeclContext is different relative to the previous test.
7646   EXPECT_EQ(ToDGCtorTP->getParam(0)->getDeclContext(),
7647             ToDGCtor->getTemplatedDecl());
7648   EXPECT_EQ(ToDGCtorTP->getParam(1)->getDeclContext(),
7649             ToDGCtor->getTemplatedDecl());
7650   EXPECT_EQ(ToDGCtorTP->getParam(2)->getDeclContext(),
7651             ToDGCtor->getTemplatedDecl());
7652   // Next line: DeclContext is different relative to the previous test.
7653   EXPECT_EQ(
7654       ToDGCopyCtor->getTemplateParameters()->getParam(0)->getDeclContext(),
7655       ToDGCtor->getTemplatedDecl());
7656   EXPECT_EQ(ToDGOther->getDescribedTemplate()
7657                 ->getTemplateParameters()
7658                 ->getParam(0)
7659                 ->getDeclContext(),
7660             ToDGOther);
7661 }
7662 
7663 TEST_P(ASTImporterOptionSpecificTestBase,
7664        ImportRecordWithLayoutRequestingExpr) {
7665   TranslationUnitDecl *FromTU = getTuDecl(
7666       R"(
7667       struct A {
7668         int idx;
7669         static void foo(A x) {
7670           (void)&"text"[x.idx];
7671         }
7672       };
7673       )",
7674       Lang_CXX11);
7675 
7676   auto *FromA = FirstDeclMatcher<CXXRecordDecl>().match(
7677       FromTU, cxxRecordDecl(hasName("A")));
7678 
7679   // Test that during import of 'foo' the record layout can be obtained without
7680   // crash.
7681   auto *ToA = Import(FromA, Lang_CXX11);
7682   EXPECT_TRUE(ToA);
7683   EXPECT_TRUE(ToA->isCompleteDefinition());
7684 }
7685 
7686 TEST_P(ASTImporterOptionSpecificTestBase,
7687        ImportRecordWithLayoutRequestingExprDifferentRecord) {
7688   TranslationUnitDecl *FromTU = getTuDecl(
7689       R"(
7690       struct B;
7691       struct A {
7692         int idx;
7693         B *b;
7694       };
7695       struct B {
7696         static void foo(A x) {
7697           (void)&"text"[x.idx];
7698         }
7699       };
7700       )",
7701       Lang_CXX11);
7702 
7703   auto *FromA = FirstDeclMatcher<CXXRecordDecl>().match(
7704       FromTU, cxxRecordDecl(hasName("A")));
7705 
7706   // Test that during import of 'foo' the record layout (of 'A') can be obtained
7707   // without crash. It is not possible to have all of the fields of 'A' imported
7708   // at that time (without big code changes).
7709   auto *ToA = Import(FromA, Lang_CXX11);
7710   EXPECT_TRUE(ToA);
7711   EXPECT_TRUE(ToA->isCompleteDefinition());
7712 }
7713 
7714 TEST_P(ASTImporterOptionSpecificTestBase, ImportInClassInitializerFromField) {
7715   // Encounter import of a field when the field already exists but has the
7716   // in-class initializer expression not yet set. Such case can occur in the AST
7717   // of generated template specializations.
7718   // The first code forces to create a template specialization of
7719   // `A<int>` but without implicit constructors.
7720   // The second ("From") code contains a variable of type `A<int>`, this
7721   // results in a template specialization that has constructors and
7722   // CXXDefaultInitExpr nodes.
7723   Decl *ToTU = getToTuDecl(
7724       R"(
7725       void f();
7726       template<typename> struct A { int X = 1; };
7727       struct B { A<int> Y; };
7728       )",
7729       Lang_CXX11);
7730   auto *ToX = FirstDeclMatcher<FieldDecl>().match(
7731       ToTU,
7732       fieldDecl(hasName("X"), hasParent(classTemplateSpecializationDecl())));
7733   ASSERT_TRUE(ToX->hasInClassInitializer());
7734   ASSERT_FALSE(ToX->getInClassInitializer());
7735 
7736   Decl *FromTU = getTuDecl(
7737       R"(
7738       void f();
7739       template<typename> struct A { int X = 1; };
7740       struct B { A<int> Y; };
7741       //
7742       A<int> Z;
7743       )",
7744       Lang_CXX11, "input1.cc");
7745   auto *FromX = FirstDeclMatcher<FieldDecl>().match(
7746       FromTU,
7747       fieldDecl(hasName("X"), hasParent(classTemplateSpecializationDecl())));
7748 
7749   auto *ToXImported = Import(FromX, Lang_CXX11);
7750   EXPECT_EQ(ToXImported, ToX);
7751   EXPECT_TRUE(ToX->getInClassInitializer());
7752 }
7753 
7754 TEST_P(ASTImporterOptionSpecificTestBase,
7755        ImportInClassInitializerFromCXXDefaultInitExpr) {
7756   // Encounter AST import of a CXXDefaultInitExpr where the "to-field"
7757   // of it exists but has the in-class initializer not set yet.
7758   Decl *ToTU = getToTuDecl(
7759       R"(
7760       namespace N {
7761         template<typename> int b;
7762         struct X;
7763       }
7764       template<typename> struct A { N::X *X = nullptr; };
7765       struct B { A<int> Y; };
7766       )",
7767       Lang_CXX14);
7768   auto *ToX = FirstDeclMatcher<FieldDecl>().match(
7769       ToTU,
7770       fieldDecl(hasName("X"), hasParent(classTemplateSpecializationDecl())));
7771   ASSERT_TRUE(ToX->hasInClassInitializer());
7772   ASSERT_FALSE(ToX->getInClassInitializer());
7773 
7774   Decl *FromTU = getTuDecl(
7775       R"(
7776       namespace N {
7777         template<typename> int b;
7778         struct X;
7779       }
7780       template<typename> struct A { N::X *X = nullptr; };
7781       struct B { A<int> Y; };
7782       //
7783       void f() {
7784         (void)A<int>{};
7785       }
7786       struct C {
7787         C(): attr(new A<int>{}){}
7788         A<int> *attr;
7789         const int value = N::b<C>;
7790       };
7791       )",
7792       Lang_CXX14, "input1.cc");
7793   auto *FromF = FirstDeclMatcher<FunctionDecl>().match(
7794       FromTU, functionDecl(hasName("f"), isDefinition()));
7795   auto *ToF = Import(FromF, Lang_CXX11);
7796   EXPECT_TRUE(ToF);
7797   EXPECT_TRUE(ToX->getInClassInitializer());
7798 }
7799 
7800 TEST_P(ASTImporterOptionSpecificTestBase, isNewDecl) {
7801   Decl *FromTU = getTuDecl(
7802       R"(
7803       int bar() {
7804         return 0;
7805       }
7806       void other() {
7807         bar();
7808       }
7809       )",
7810       Lang_CXX11);
7811   Decl *ToTU = getToTuDecl(
7812       R"(
7813       int bar() {
7814         return 0;
7815       }
7816       )",
7817       Lang_CXX11);
7818   auto *FromOther = FirstDeclMatcher<FunctionDecl>().match(
7819       FromTU, functionDecl(hasName("other")));
7820   ASSERT_TRUE(FromOther);
7821 
7822   auto *ToOther = Import(FromOther, Lang_CXX11);
7823   ASSERT_TRUE(ToOther);
7824 
7825   auto *ToBar = FirstDeclMatcher<FunctionDecl>().match(
7826       ToTU, functionDecl(hasName("bar")));
7827 
7828   EXPECT_TRUE(SharedStatePtr->isNewDecl(ToOther));
7829   EXPECT_FALSE(SharedStatePtr->isNewDecl(ToBar));
7830 }
7831 
7832 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ASTImporterLookupTableTest,
7833                          DefaultTestValuesForRunOptions);
7834 
7835 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportPath,
7836                          ::testing::Values(std::vector<std::string>()));
7837 
7838 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportExpr,
7839                          DefaultTestValuesForRunOptions);
7840 
7841 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFixedPointExpr,
7842                          ExtendWithOptions(DefaultTestArrayForRunOptions,
7843                                            std::vector<std::string>{
7844                                                "-ffixed-point"}));
7845 
7846 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportBlock,
7847                          ExtendWithOptions(DefaultTestArrayForRunOptions,
7848                                            std::vector<std::string>{
7849                                                "-fblocks"}));
7850 
7851 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportType,
7852                          DefaultTestValuesForRunOptions);
7853 
7854 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportDecl,
7855                          DefaultTestValuesForRunOptions);
7856 
7857 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ASTImporterOptionSpecificTestBase,
7858                          DefaultTestValuesForRunOptions);
7859 
7860 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ErrorHandlingTest,
7861                          DefaultTestValuesForRunOptions);
7862 
7863 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, RedirectingImporterTest,
7864                          DefaultTestValuesForRunOptions);
7865 
7866 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFunctions,
7867                          DefaultTestValuesForRunOptions);
7868 
7869 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportAutoFunctions,
7870                          DefaultTestValuesForRunOptions);
7871 
7872 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFunctionTemplates,
7873                          DefaultTestValuesForRunOptions);
7874 
7875 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFriendFunctionTemplates,
7876                          DefaultTestValuesForRunOptions);
7877 
7878 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportClasses,
7879                          DefaultTestValuesForRunOptions);
7880 
7881 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFriendFunctions,
7882                          DefaultTestValuesForRunOptions);
7883 
7884 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportFriendClasses,
7885                          DefaultTestValuesForRunOptions);
7886 
7887 INSTANTIATE_TEST_SUITE_P(ParameterizedTests,
7888                          ImportFunctionTemplateSpecializations,
7889                          DefaultTestValuesForRunOptions);
7890 
7891 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportImplicitMethods,
7892                          DefaultTestValuesForRunOptions);
7893 
7894 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportVariables,
7895                          DefaultTestValuesForRunOptions);
7896 
7897 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, LLDBLookupTest,
7898                          DefaultTestValuesForRunOptions);
7899 
7900 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportSourceLocations,
7901                          DefaultTestValuesForRunOptions);
7902 
7903 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportWithExternalSource,
7904                          DefaultTestValuesForRunOptions);
7905 
7906 INSTANTIATE_TEST_SUITE_P(ParameterizedTests, ImportAttributes,
7907                          DefaultTestValuesForRunOptions);
7908 
7909 } // end namespace ast_matchers
7910 } // end namespace clang
7911