1 //===- unittests/Basic/FileMangerTest.cpp ------------ FileManger tests ---===//
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 #include "clang/Basic/FileManager.h"
10 #include "clang/Basic/FileSystemOptions.h"
11 #include "clang/Basic/FileSystemStatCache.h"
12 #include "llvm/ADT/STLExtras.h"
13 #include "llvm/Support/Path.h"
14 #include "llvm/Support/VirtualFileSystem.h"
15 #include "llvm/Testing/Support/Error.h"
16 #include "gtest/gtest.h"
17 
18 using namespace llvm;
19 using namespace clang;
20 
21 namespace {
22 
23 // Used to create a fake file system for running the tests with such
24 // that the tests are not affected by the structure/contents of the
25 // file system on the machine running the tests.
26 class FakeStatCache : public FileSystemStatCache {
27 private:
28   // Maps a file/directory path to its desired stat result.  Anything
29   // not in this map is considered to not exist in the file system.
30   llvm::StringMap<llvm::vfs::Status, llvm::BumpPtrAllocator> StatCalls;
31 
32   void InjectFileOrDirectory(const char *Path, ino_t INode, bool IsFile,
33                              const char *StatPath) {
34     SmallString<128> NormalizedPath(Path);
35     SmallString<128> NormalizedStatPath;
36     if (is_style_posix(llvm::sys::path::Style::native)) {
37       llvm::sys::path::native(NormalizedPath);
38       Path = NormalizedPath.c_str();
39 
40       if (StatPath) {
41         NormalizedStatPath = StatPath;
42         llvm::sys::path::native(NormalizedStatPath);
43         StatPath = NormalizedStatPath.c_str();
44       }
45     }
46 
47     if (!StatPath)
48       StatPath = Path;
49 
50     auto fileType = IsFile ?
51       llvm::sys::fs::file_type::regular_file :
52       llvm::sys::fs::file_type::directory_file;
53     llvm::vfs::Status Status(StatPath, llvm::sys::fs::UniqueID(1, INode),
54                              /*MTime*/{}, /*User*/0, /*Group*/0,
55                              /*Size*/0, fileType,
56                              llvm::sys::fs::perms::all_all);
57     StatCalls[Path] = Status;
58   }
59 
60 public:
61   // Inject a file with the given inode value to the fake file system.
62   void InjectFile(const char *Path, ino_t INode,
63                   const char *StatPath = nullptr) {
64     InjectFileOrDirectory(Path, INode, /*IsFile=*/true, StatPath);
65   }
66 
67   // Inject a directory with the given inode value to the fake file system.
68   void InjectDirectory(const char *Path, ino_t INode) {
69     InjectFileOrDirectory(Path, INode, /*IsFile=*/false, nullptr);
70   }
71 
72   // Implement FileSystemStatCache::getStat().
73   std::error_code getStat(StringRef Path, llvm::vfs::Status &Status,
74                           bool isFile,
75                           std::unique_ptr<llvm::vfs::File> *F,
76                           llvm::vfs::FileSystem &FS) override {
77     SmallString<128> NormalizedPath(Path);
78     if (is_style_posix(llvm::sys::path::Style::native)) {
79       llvm::sys::path::native(NormalizedPath);
80       Path = NormalizedPath.c_str();
81     }
82 
83     if (StatCalls.count(Path) != 0) {
84       Status = StatCalls[Path];
85       return std::error_code();
86     }
87 
88     return std::make_error_code(std::errc::no_such_file_or_directory);
89   }
90 };
91 
92 // The test fixture.
93 class FileManagerTest : public ::testing::Test {
94  protected:
95   FileManagerTest() : manager(options) {
96   }
97 
98   FileSystemOptions options;
99   FileManager manager;
100 };
101 
102 // When a virtual file is added, its getDir() field is set correctly
103 // (not NULL, correct name).
104 TEST_F(FileManagerTest, getVirtualFileSetsTheDirFieldCorrectly) {
105   const FileEntry *file = manager.getVirtualFile("foo.cpp", 42, 0);
106   ASSERT_TRUE(file != nullptr);
107 
108   const DirectoryEntry *dir = file->getDir();
109   ASSERT_TRUE(dir != nullptr);
110   EXPECT_EQ(".", dir->getName());
111 
112   file = manager.getVirtualFile("x/y/z.cpp", 42, 0);
113   ASSERT_TRUE(file != nullptr);
114 
115   dir = file->getDir();
116   ASSERT_TRUE(dir != nullptr);
117   EXPECT_EQ("x/y", dir->getName());
118 }
119 
120 // Before any virtual file is added, no virtual directory exists.
121 TEST_F(FileManagerTest, NoVirtualDirectoryExistsBeforeAVirtualFileIsAdded) {
122   // An empty FakeStatCache causes all stat calls made by the
123   // FileManager to report "file/directory doesn't exist".  This
124   // avoids the possibility of the result of this test being affected
125   // by what's in the real file system.
126   manager.setStatCache(std::make_unique<FakeStatCache>());
127 
128   ASSERT_FALSE(manager.getDirectory("virtual/dir/foo"));
129   ASSERT_FALSE(manager.getDirectory("virtual/dir"));
130   ASSERT_FALSE(manager.getDirectory("virtual"));
131 }
132 
133 // When a virtual file is added, all of its ancestors should be created.
134 TEST_F(FileManagerTest, getVirtualFileCreatesDirectoryEntriesForAncestors) {
135   // Fake an empty real file system.
136   manager.setStatCache(std::make_unique<FakeStatCache>());
137 
138   manager.getVirtualFile("virtual/dir/bar.h", 100, 0);
139   ASSERT_FALSE(manager.getDirectory("virtual/dir/foo"));
140 
141   auto dir = manager.getDirectory("virtual/dir");
142   ASSERT_TRUE(dir);
143   EXPECT_EQ("virtual/dir", (*dir)->getName());
144 
145   dir = manager.getDirectory("virtual");
146   ASSERT_TRUE(dir);
147   EXPECT_EQ("virtual", (*dir)->getName());
148 }
149 
150 // getFile() returns non-NULL if a real file exists at the given path.
151 TEST_F(FileManagerTest, getFileReturnsValidFileEntryForExistingRealFile) {
152   // Inject fake files into the file system.
153   auto statCache = std::make_unique<FakeStatCache>();
154   statCache->InjectDirectory("/tmp", 42);
155   statCache->InjectFile("/tmp/test", 43);
156 
157 #ifdef _WIN32
158   const char *DirName = "C:.";
159   const char *FileName = "C:test";
160   statCache->InjectDirectory(DirName, 44);
161   statCache->InjectFile(FileName, 45);
162 #endif
163 
164   manager.setStatCache(std::move(statCache));
165 
166   auto file = manager.getFile("/tmp/test");
167   ASSERT_TRUE(file);
168   ASSERT_TRUE((*file)->isValid());
169   EXPECT_EQ("/tmp/test", (*file)->getName());
170 
171   const DirectoryEntry *dir = (*file)->getDir();
172   ASSERT_TRUE(dir != nullptr);
173   EXPECT_EQ("/tmp", dir->getName());
174 
175 #ifdef _WIN32
176   file = manager.getFile(FileName);
177   ASSERT_TRUE(file);
178 
179   dir = (*file)->getDir();
180   ASSERT_TRUE(dir != NULL);
181   EXPECT_EQ(DirName, dir->getName());
182 #endif
183 }
184 
185 // getFile() returns non-NULL if a virtual file exists at the given path.
186 TEST_F(FileManagerTest, getFileReturnsValidFileEntryForExistingVirtualFile) {
187   // Fake an empty real file system.
188   manager.setStatCache(std::make_unique<FakeStatCache>());
189 
190   manager.getVirtualFile("virtual/dir/bar.h", 100, 0);
191   auto file = manager.getFile("virtual/dir/bar.h");
192   ASSERT_TRUE(file);
193   ASSERT_TRUE((*file)->isValid());
194   EXPECT_EQ("virtual/dir/bar.h", (*file)->getName());
195 
196   const DirectoryEntry *dir = (*file)->getDir();
197   ASSERT_TRUE(dir != nullptr);
198   EXPECT_EQ("virtual/dir", dir->getName());
199 }
200 
201 // getFile() returns different FileEntries for different paths when
202 // there's no aliasing.
203 TEST_F(FileManagerTest, getFileReturnsDifferentFileEntriesForDifferentFiles) {
204   // Inject two fake files into the file system.  Different inodes
205   // mean the files are not symlinked together.
206   auto statCache = std::make_unique<FakeStatCache>();
207   statCache->InjectDirectory(".", 41);
208   statCache->InjectFile("foo.cpp", 42);
209   statCache->InjectFile("bar.cpp", 43);
210   manager.setStatCache(std::move(statCache));
211 
212   auto fileFoo = manager.getFile("foo.cpp");
213   auto fileBar = manager.getFile("bar.cpp");
214   ASSERT_TRUE(fileFoo);
215   ASSERT_TRUE((*fileFoo)->isValid());
216   ASSERT_TRUE(fileBar);
217   ASSERT_TRUE((*fileBar)->isValid());
218   EXPECT_NE(*fileFoo, *fileBar);
219 }
220 
221 // getFile() returns an error if neither a real file nor a virtual file
222 // exists at the given path.
223 TEST_F(FileManagerTest, getFileReturnsErrorForNonexistentFile) {
224   // Inject a fake foo.cpp into the file system.
225   auto statCache = std::make_unique<FakeStatCache>();
226   statCache->InjectDirectory(".", 41);
227   statCache->InjectFile("foo.cpp", 42);
228   statCache->InjectDirectory("MyDirectory", 49);
229   manager.setStatCache(std::move(statCache));
230 
231   // Create a virtual bar.cpp file.
232   manager.getVirtualFile("bar.cpp", 200, 0);
233 
234   auto file = manager.getFile("xyz.txt");
235   ASSERT_FALSE(file);
236   ASSERT_EQ(file.getError(), std::errc::no_such_file_or_directory);
237 
238   auto readingDirAsFile = manager.getFile("MyDirectory");
239   ASSERT_FALSE(readingDirAsFile);
240   ASSERT_EQ(readingDirAsFile.getError(), std::errc::is_a_directory);
241 
242   auto readingFileAsDir = manager.getDirectory("foo.cpp");
243   ASSERT_FALSE(readingFileAsDir);
244   ASSERT_EQ(readingFileAsDir.getError(), std::errc::not_a_directory);
245 }
246 
247 // The following tests apply to Unix-like system only.
248 
249 #ifndef _WIN32
250 
251 // getFile() returns the same FileEntry for real files that are aliases.
252 TEST_F(FileManagerTest, getFileReturnsSameFileEntryForAliasedRealFiles) {
253   // Inject two real files with the same inode.
254   auto statCache = std::make_unique<FakeStatCache>();
255   statCache->InjectDirectory("abc", 41);
256   statCache->InjectFile("abc/foo.cpp", 42);
257   statCache->InjectFile("abc/bar.cpp", 42);
258   manager.setStatCache(std::move(statCache));
259 
260   auto f1 = manager.getFile("abc/foo.cpp");
261   auto f2 = manager.getFile("abc/bar.cpp");
262 
263   EXPECT_EQ(f1 ? *f1 : nullptr,
264             f2 ? *f2 : nullptr);
265 
266   // Check that getFileRef also does the right thing.
267   auto r1 = manager.getFileRef("abc/foo.cpp");
268   auto r2 = manager.getFileRef("abc/bar.cpp");
269   ASSERT_FALSE(!r1);
270   ASSERT_FALSE(!r2);
271 
272   EXPECT_EQ("abc/foo.cpp", r1->getName());
273   EXPECT_EQ("abc/bar.cpp", r2->getName());
274   EXPECT_EQ((f1 ? *f1 : nullptr), &r1->getFileEntry());
275   EXPECT_EQ((f2 ? *f2 : nullptr), &r2->getFileEntry());
276 }
277 
278 TEST_F(FileManagerTest, getFileRefReturnsCorrectNameForDifferentStatPath) {
279   // Inject files with the same inode, but where some files have a stat that
280   // gives a different name. This is adding coverage for stat behaviour
281   // triggered by the RedirectingFileSystem for 'use-external-name' that
282   // FileManager::getFileRef has special logic for.
283   auto StatCache = std::make_unique<FakeStatCache>();
284   StatCache->InjectDirectory("dir", 40);
285   StatCache->InjectFile("dir/f1.cpp", 41);
286   StatCache->InjectFile("dir/f1-alias.cpp", 41, "dir/f1.cpp");
287   StatCache->InjectFile("dir/f2.cpp", 42);
288   StatCache->InjectFile("dir/f2-alias.cpp", 42, "dir/f2.cpp");
289 
290   // This unintuitive rename-the-file-on-stat behaviour supports how the
291   // RedirectingFileSystem VFS layer responds to stats. However, even if you
292   // have two layers, you should only get a single filename back. As such the
293   // following stat cache behaviour is not supported (the correct stat entry
294   // for a double-redirection would be "dir/f1.cpp") and the getFileRef below
295   // should assert.
296   StatCache->InjectFile("dir/f1-alias-alias.cpp", 41, "dir/f1-alias.cpp");
297 
298   manager.setStatCache(std::move(StatCache));
299 
300   // With F1, test accessing the non-redirected name first.
301   auto F1 = manager.getFileRef("dir/f1.cpp");
302   auto F1Alias = manager.getFileRef("dir/f1-alias.cpp");
303   auto F1Alias2 = manager.getFileRef("dir/f1-alias.cpp");
304   ASSERT_FALSE(!F1);
305   ASSERT_FALSE(!F1Alias);
306   ASSERT_FALSE(!F1Alias2);
307   EXPECT_EQ("dir/f1.cpp", F1->getName());
308   EXPECT_EQ("dir/f1.cpp", F1->getFileEntry().getName());
309   EXPECT_EQ("dir/f1.cpp", F1Alias->getName());
310   EXPECT_EQ("dir/f1.cpp", F1Alias2->getName());
311   EXPECT_EQ(&F1->getFileEntry(), &F1Alias->getFileEntry());
312   EXPECT_EQ(&F1->getFileEntry(), &F1Alias2->getFileEntry());
313 
314 #if !defined(NDEBUG) && GTEST_HAS_DEATH_TEST
315   EXPECT_DEATH((void)manager.getFileRef("dir/f1-alias-alias.cpp"),
316                "filename redirected to a non-canonical filename?");
317 #endif
318 
319   // With F2, test accessing the redirected name first.
320   auto F2Alias = manager.getFileRef("dir/f2-alias.cpp");
321   auto F2 = manager.getFileRef("dir/f2.cpp");
322   auto F2Alias2 = manager.getFileRef("dir/f2-alias.cpp");
323   ASSERT_FALSE(!F2);
324   ASSERT_FALSE(!F2Alias);
325   ASSERT_FALSE(!F2Alias2);
326   EXPECT_EQ("dir/f2.cpp", F2->getName());
327   EXPECT_EQ("dir/f2.cpp", F2->getFileEntry().getName());
328   EXPECT_EQ("dir/f2.cpp", F2Alias->getName());
329   EXPECT_EQ("dir/f2.cpp", F2Alias2->getName());
330   EXPECT_EQ(&F2->getFileEntry(), &F2Alias->getFileEntry());
331   EXPECT_EQ(&F2->getFileEntry(), &F2Alias2->getFileEntry());
332 }
333 
334 // getFile() returns the same FileEntry for virtual files that have
335 // corresponding real files that are aliases.
336 TEST_F(FileManagerTest, getFileReturnsSameFileEntryForAliasedVirtualFiles) {
337   // Inject two real files with the same inode.
338   auto statCache = std::make_unique<FakeStatCache>();
339   statCache->InjectDirectory("abc", 41);
340   statCache->InjectFile("abc/foo.cpp", 42);
341   statCache->InjectFile("abc/bar.cpp", 42);
342   manager.setStatCache(std::move(statCache));
343 
344   ASSERT_TRUE(manager.getVirtualFile("abc/foo.cpp", 100, 0)->isValid());
345   ASSERT_TRUE(manager.getVirtualFile("abc/bar.cpp", 200, 0)->isValid());
346 
347   auto f1 = manager.getFile("abc/foo.cpp");
348   auto f2 = manager.getFile("abc/bar.cpp");
349 
350   EXPECT_EQ(f1 ? *f1 : nullptr,
351             f2 ? *f2 : nullptr);
352 }
353 
354 TEST_F(FileManagerTest, getFileRefEquality) {
355   auto StatCache = std::make_unique<FakeStatCache>();
356   StatCache->InjectDirectory("dir", 40);
357   StatCache->InjectFile("dir/f1.cpp", 41);
358   StatCache->InjectFile("dir/f1-also.cpp", 41);
359   StatCache->InjectFile("dir/f1-redirect.cpp", 41, "dir/f1.cpp");
360   StatCache->InjectFile("dir/f2.cpp", 42);
361   manager.setStatCache(std::move(StatCache));
362 
363   auto F1 = manager.getFileRef("dir/f1.cpp");
364   auto F1Again = manager.getFileRef("dir/f1.cpp");
365   auto F1Also = manager.getFileRef("dir/f1-also.cpp");
366   auto F1Redirect = manager.getFileRef("dir/f1-redirect.cpp");
367   auto F2 = manager.getFileRef("dir/f2.cpp");
368 
369   // Check Expected<FileEntryRef> for error.
370   ASSERT_FALSE(!F1);
371   ASSERT_FALSE(!F1Also);
372   ASSERT_FALSE(!F1Again);
373   ASSERT_FALSE(!F1Redirect);
374   ASSERT_FALSE(!F2);
375 
376   // Check names.
377   EXPECT_EQ("dir/f1.cpp", F1->getName());
378   EXPECT_EQ("dir/f1.cpp", F1Again->getName());
379   EXPECT_EQ("dir/f1-also.cpp", F1Also->getName());
380   EXPECT_EQ("dir/f1.cpp", F1Redirect->getName());
381   EXPECT_EQ("dir/f2.cpp", F2->getName());
382 
383   // Compare against FileEntry*.
384   EXPECT_EQ(&F1->getFileEntry(), *F1);
385   EXPECT_EQ(*F1, &F1->getFileEntry());
386   EXPECT_NE(&F2->getFileEntry(), *F1);
387   EXPECT_NE(*F1, &F2->getFileEntry());
388 
389   // Compare using ==.
390   EXPECT_EQ(*F1, *F1Also);
391   EXPECT_EQ(*F1, *F1Again);
392   EXPECT_EQ(*F1, *F1Redirect);
393   EXPECT_EQ(*F1Also, *F1Redirect);
394   EXPECT_NE(*F2, *F1);
395   EXPECT_NE(*F2, *F1Also);
396   EXPECT_NE(*F2, *F1Again);
397   EXPECT_NE(*F2, *F1Redirect);
398 
399   // Compare using isSameRef.
400   EXPECT_TRUE(F1->isSameRef(*F1Again));
401   EXPECT_TRUE(F1->isSameRef(*F1Redirect));
402   EXPECT_FALSE(F1->isSameRef(*F1Also));
403   EXPECT_FALSE(F1->isSameRef(*F2));
404 }
405 
406 // getFile() Should return the same entry as getVirtualFile if the file actually
407 // is a virtual file, even if the name is not exactly the same (but is after
408 // normalisation done by the file system, like on Windows). This can be checked
409 // here by checking the size.
410 TEST_F(FileManagerTest, getVirtualFileWithDifferentName) {
411   // Inject fake files into the file system.
412   auto statCache = std::make_unique<FakeStatCache>();
413   statCache->InjectDirectory("c:\\tmp", 42);
414   statCache->InjectFile("c:\\tmp\\test", 43);
415 
416   manager.setStatCache(std::move(statCache));
417 
418   // Inject the virtual file:
419   const FileEntry *file1 = manager.getVirtualFile("c:\\tmp\\test", 123, 1);
420   ASSERT_TRUE(file1 != nullptr);
421   ASSERT_TRUE(file1->isValid());
422   EXPECT_EQ(43U, file1->getUniqueID().getFile());
423   EXPECT_EQ(123, file1->getSize());
424 
425   // Lookup the virtual file with a different name:
426   auto file2 = manager.getFile("c:/tmp/test", 100, 1);
427   ASSERT_TRUE(file2);
428   ASSERT_TRUE((*file2)->isValid());
429   // Check that it's the same UFE:
430   EXPECT_EQ(file1, *file2);
431   EXPECT_EQ(43U, (*file2)->getUniqueID().getFile());
432   // Check that the contents of the UFE are not overwritten by the entry in the
433   // filesystem:
434   EXPECT_EQ(123, (*file2)->getSize());
435 }
436 
437 #endif  // !_WIN32
438 
439 static StringRef getSystemRoot() {
440   return is_style_windows(llvm::sys::path::Style::native) ? "C:/" : "/";
441 }
442 
443 TEST_F(FileManagerTest, makeAbsoluteUsesVFS) {
444   // FIXME: Should this be using a root path / call getSystemRoot()? For now,
445   // avoiding that and leaving the test as-is.
446   SmallString<64> CustomWorkingDir =
447       is_style_windows(llvm::sys::path::Style::native) ? StringRef("C:")
448                                                        : StringRef("/");
449   llvm::sys::path::append(CustomWorkingDir, "some", "weird", "path");
450 
451   auto FS = IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>(
452       new llvm::vfs::InMemoryFileSystem);
453   // setCurrentworkingdirectory must finish without error.
454   ASSERT_TRUE(!FS->setCurrentWorkingDirectory(CustomWorkingDir));
455 
456   FileSystemOptions Opts;
457   FileManager Manager(Opts, FS);
458 
459   SmallString<64> Path("a/foo.cpp");
460 
461   SmallString<64> ExpectedResult(CustomWorkingDir);
462   llvm::sys::path::append(ExpectedResult, Path);
463 
464   ASSERT_TRUE(Manager.makeAbsolutePath(Path));
465   EXPECT_EQ(Path, ExpectedResult);
466 }
467 
468 // getVirtualFile should always fill the real path.
469 TEST_F(FileManagerTest, getVirtualFileFillsRealPathName) {
470   SmallString<64> CustomWorkingDir = getSystemRoot();
471 
472   auto FS = IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>(
473       new llvm::vfs::InMemoryFileSystem);
474   // setCurrentworkingdirectory must finish without error.
475   ASSERT_TRUE(!FS->setCurrentWorkingDirectory(CustomWorkingDir));
476 
477   FileSystemOptions Opts;
478   FileManager Manager(Opts, FS);
479 
480   // Inject fake files into the file system.
481   auto statCache = std::make_unique<FakeStatCache>();
482   statCache->InjectDirectory("/tmp", 42);
483   statCache->InjectFile("/tmp/test", 43);
484 
485   Manager.setStatCache(std::move(statCache));
486 
487   // Check for real path.
488   const FileEntry *file = Manager.getVirtualFile("/tmp/test", 123, 1);
489   ASSERT_TRUE(file != nullptr);
490   ASSERT_TRUE(file->isValid());
491   SmallString<64> ExpectedResult = CustomWorkingDir;
492 
493   llvm::sys::path::append(ExpectedResult, "tmp", "test");
494   EXPECT_EQ(file->tryGetRealPathName(), ExpectedResult);
495 }
496 
497 TEST_F(FileManagerTest, getFileDontOpenRealPath) {
498   SmallString<64> CustomWorkingDir = getSystemRoot();
499 
500   auto FS = IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>(
501       new llvm::vfs::InMemoryFileSystem);
502   // setCurrentworkingdirectory must finish without error.
503   ASSERT_TRUE(!FS->setCurrentWorkingDirectory(CustomWorkingDir));
504 
505   FileSystemOptions Opts;
506   FileManager Manager(Opts, FS);
507 
508   // Inject fake files into the file system.
509   auto statCache = std::make_unique<FakeStatCache>();
510   statCache->InjectDirectory("/tmp", 42);
511   statCache->InjectFile("/tmp/test", 43);
512 
513   Manager.setStatCache(std::move(statCache));
514 
515   // Check for real path.
516   auto file = Manager.getFile("/tmp/test", /*OpenFile=*/false);
517   ASSERT_TRUE(file);
518   ASSERT_TRUE((*file)->isValid());
519   SmallString<64> ExpectedResult = CustomWorkingDir;
520 
521   llvm::sys::path::append(ExpectedResult, "tmp", "test");
522   EXPECT_EQ((*file)->tryGetRealPathName(), ExpectedResult);
523 }
524 
525 TEST_F(FileManagerTest, getBypassFile) {
526   SmallString<64> CustomWorkingDir;
527 #ifdef _WIN32
528   CustomWorkingDir = "C:/";
529 #else
530   CustomWorkingDir = "/";
531 #endif
532 
533   auto FS = IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem>(
534       new llvm::vfs::InMemoryFileSystem);
535   // setCurrentworkingdirectory must finish without error.
536   ASSERT_TRUE(!FS->setCurrentWorkingDirectory(CustomWorkingDir));
537 
538   FileSystemOptions Opts;
539   FileManager Manager(Opts, FS);
540 
541   // Inject fake files into the file system.
542   auto Cache = std::make_unique<FakeStatCache>();
543   Cache->InjectDirectory("/tmp", 42);
544   Cache->InjectFile("/tmp/test", 43);
545   Manager.setStatCache(std::move(Cache));
546 
547   // Set up a virtual file with a different size than FakeStatCache uses.
548   const FileEntry *File = Manager.getVirtualFile("/tmp/test", /*Size=*/10, 0);
549   ASSERT_TRUE(File);
550   const FileEntry &FE = *File;
551   EXPECT_TRUE(FE.isValid());
552   EXPECT_EQ(FE.getSize(), 10);
553 
554   // Calling a second time should not affect the UID or size.
555   unsigned VirtualUID = FE.getUID();
556   llvm::Optional<FileEntryRef> SearchRef;
557   ASSERT_THAT_ERROR(Manager.getFileRef("/tmp/test").moveInto(SearchRef),
558                     Succeeded());
559   EXPECT_EQ(&FE, &SearchRef->getFileEntry());
560   EXPECT_EQ(FE.getUID(), VirtualUID);
561   EXPECT_EQ(FE.getSize(), 10);
562 
563   // Bypass the file.
564   llvm::Optional<FileEntryRef> BypassRef =
565       Manager.getBypassFile(File->getLastRef());
566   ASSERT_TRUE(BypassRef);
567   EXPECT_TRUE(BypassRef->isValid());
568   EXPECT_EQ("/tmp/test", BypassRef->getName());
569 
570   // Check that it's different in the right ways.
571   EXPECT_NE(&BypassRef->getFileEntry(), File);
572   EXPECT_NE(BypassRef->getUID(), VirtualUID);
573   EXPECT_NE(BypassRef->getSize(), FE.getSize());
574 
575   // The virtual file should still be returned when searching.
576   ASSERT_THAT_ERROR(Manager.getFileRef("/tmp/test").moveInto(SearchRef),
577                     Succeeded());
578   EXPECT_EQ(&FE, &SearchRef->getFileEntry());
579 }
580 
581 } // anonymous namespace
582