1 //===--- Format.cpp - Format C++ code -------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// \brief This file implements functions declared in Format.h. This will be
12 /// split into separate files as we go.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "clang/Format/Format.h"
17 #include "AffectedRangeManager.h"
18 #include "ContinuationIndenter.h"
19 #include "FormatTokenLexer.h"
20 #include "NamespaceEndCommentsFixer.h"
21 #include "SortJavaScriptImports.h"
22 #include "TokenAnalyzer.h"
23 #include "TokenAnnotator.h"
24 #include "UnwrappedLineFormatter.h"
25 #include "UnwrappedLineParser.h"
26 #include "WhitespaceManager.h"
27 #include "clang/Basic/Diagnostic.h"
28 #include "clang/Basic/DiagnosticOptions.h"
29 #include "clang/Basic/SourceManager.h"
30 #include "clang/Basic/VirtualFileSystem.h"
31 #include "clang/Lex/Lexer.h"
32 #include "llvm/ADT/STLExtras.h"
33 #include "llvm/Support/Allocator.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Support/Path.h"
36 #include "llvm/Support/Regex.h"
37 #include "llvm/Support/YAMLTraits.h"
38 #include <algorithm>
39 #include <memory>
40 #include <string>
41 
42 #define DEBUG_TYPE "format-formatter"
43 
44 using clang::format::FormatStyle;
45 
46 LLVM_YAML_IS_FLOW_SEQUENCE_VECTOR(std::string)
47 LLVM_YAML_IS_SEQUENCE_VECTOR(clang::format::FormatStyle::IncludeCategory)
48 
49 namespace llvm {
50 namespace yaml {
51 template <> struct ScalarEnumerationTraits<FormatStyle::LanguageKind> {
52   static void enumeration(IO &IO, FormatStyle::LanguageKind &Value) {
53     IO.enumCase(Value, "Cpp", FormatStyle::LK_Cpp);
54     IO.enumCase(Value, "Java", FormatStyle::LK_Java);
55     IO.enumCase(Value, "JavaScript", FormatStyle::LK_JavaScript);
56     IO.enumCase(Value, "ObjC", FormatStyle::LK_ObjC);
57     IO.enumCase(Value, "Proto", FormatStyle::LK_Proto);
58     IO.enumCase(Value, "TableGen", FormatStyle::LK_TableGen);
59   }
60 };
61 
62 template <> struct ScalarEnumerationTraits<FormatStyle::LanguageStandard> {
63   static void enumeration(IO &IO, FormatStyle::LanguageStandard &Value) {
64     IO.enumCase(Value, "Cpp03", FormatStyle::LS_Cpp03);
65     IO.enumCase(Value, "C++03", FormatStyle::LS_Cpp03);
66     IO.enumCase(Value, "Cpp11", FormatStyle::LS_Cpp11);
67     IO.enumCase(Value, "C++11", FormatStyle::LS_Cpp11);
68     IO.enumCase(Value, "Auto", FormatStyle::LS_Auto);
69   }
70 };
71 
72 template <> struct ScalarEnumerationTraits<FormatStyle::UseTabStyle> {
73   static void enumeration(IO &IO, FormatStyle::UseTabStyle &Value) {
74     IO.enumCase(Value, "Never", FormatStyle::UT_Never);
75     IO.enumCase(Value, "false", FormatStyle::UT_Never);
76     IO.enumCase(Value, "Always", FormatStyle::UT_Always);
77     IO.enumCase(Value, "true", FormatStyle::UT_Always);
78     IO.enumCase(Value, "ForIndentation", FormatStyle::UT_ForIndentation);
79     IO.enumCase(Value, "ForContinuationAndIndentation",
80                 FormatStyle::UT_ForContinuationAndIndentation);
81   }
82 };
83 
84 template <> struct ScalarEnumerationTraits<FormatStyle::JavaScriptQuoteStyle> {
85   static void enumeration(IO &IO, FormatStyle::JavaScriptQuoteStyle &Value) {
86     IO.enumCase(Value, "Leave", FormatStyle::JSQS_Leave);
87     IO.enumCase(Value, "Single", FormatStyle::JSQS_Single);
88     IO.enumCase(Value, "Double", FormatStyle::JSQS_Double);
89   }
90 };
91 
92 template <> struct ScalarEnumerationTraits<FormatStyle::ShortFunctionStyle> {
93   static void enumeration(IO &IO, FormatStyle::ShortFunctionStyle &Value) {
94     IO.enumCase(Value, "None", FormatStyle::SFS_None);
95     IO.enumCase(Value, "false", FormatStyle::SFS_None);
96     IO.enumCase(Value, "All", FormatStyle::SFS_All);
97     IO.enumCase(Value, "true", FormatStyle::SFS_All);
98     IO.enumCase(Value, "Inline", FormatStyle::SFS_Inline);
99     IO.enumCase(Value, "Empty", FormatStyle::SFS_Empty);
100   }
101 };
102 
103 template <> struct ScalarEnumerationTraits<FormatStyle::BinaryOperatorStyle> {
104   static void enumeration(IO &IO, FormatStyle::BinaryOperatorStyle &Value) {
105     IO.enumCase(Value, "All", FormatStyle::BOS_All);
106     IO.enumCase(Value, "true", FormatStyle::BOS_All);
107     IO.enumCase(Value, "None", FormatStyle::BOS_None);
108     IO.enumCase(Value, "false", FormatStyle::BOS_None);
109     IO.enumCase(Value, "NonAssignment", FormatStyle::BOS_NonAssignment);
110   }
111 };
112 
113 template <> struct ScalarEnumerationTraits<FormatStyle::BraceBreakingStyle> {
114   static void enumeration(IO &IO, FormatStyle::BraceBreakingStyle &Value) {
115     IO.enumCase(Value, "Attach", FormatStyle::BS_Attach);
116     IO.enumCase(Value, "Linux", FormatStyle::BS_Linux);
117     IO.enumCase(Value, "Mozilla", FormatStyle::BS_Mozilla);
118     IO.enumCase(Value, "Stroustrup", FormatStyle::BS_Stroustrup);
119     IO.enumCase(Value, "Allman", FormatStyle::BS_Allman);
120     IO.enumCase(Value, "GNU", FormatStyle::BS_GNU);
121     IO.enumCase(Value, "WebKit", FormatStyle::BS_WebKit);
122     IO.enumCase(Value, "Custom", FormatStyle::BS_Custom);
123   }
124 };
125 
126 template <> struct ScalarEnumerationTraits<FormatStyle::BreakConstructorInitializersStyle> {
127   static void enumeration(IO &IO, FormatStyle::BreakConstructorInitializersStyle &Value) {
128     IO.enumCase(Value, "BeforeColon", FormatStyle::BCIS_BeforeColon);
129     IO.enumCase(Value, "BeforeComma", FormatStyle::BCIS_BeforeComma);
130     IO.enumCase(Value, "AfterColon", FormatStyle::BCIS_AfterColon);
131   }
132 };
133 
134 template <>
135 struct ScalarEnumerationTraits<FormatStyle::ReturnTypeBreakingStyle> {
136   static void enumeration(IO &IO, FormatStyle::ReturnTypeBreakingStyle &Value) {
137     IO.enumCase(Value, "None", FormatStyle::RTBS_None);
138     IO.enumCase(Value, "All", FormatStyle::RTBS_All);
139     IO.enumCase(Value, "TopLevel", FormatStyle::RTBS_TopLevel);
140     IO.enumCase(Value, "TopLevelDefinitions",
141                 FormatStyle::RTBS_TopLevelDefinitions);
142     IO.enumCase(Value, "AllDefinitions", FormatStyle::RTBS_AllDefinitions);
143   }
144 };
145 
146 template <>
147 struct ScalarEnumerationTraits<FormatStyle::DefinitionReturnTypeBreakingStyle> {
148   static void
149   enumeration(IO &IO, FormatStyle::DefinitionReturnTypeBreakingStyle &Value) {
150     IO.enumCase(Value, "None", FormatStyle::DRTBS_None);
151     IO.enumCase(Value, "All", FormatStyle::DRTBS_All);
152     IO.enumCase(Value, "TopLevel", FormatStyle::DRTBS_TopLevel);
153 
154     // For backward compatibility.
155     IO.enumCase(Value, "false", FormatStyle::DRTBS_None);
156     IO.enumCase(Value, "true", FormatStyle::DRTBS_All);
157   }
158 };
159 
160 template <>
161 struct ScalarEnumerationTraits<FormatStyle::NamespaceIndentationKind> {
162   static void enumeration(IO &IO,
163                           FormatStyle::NamespaceIndentationKind &Value) {
164     IO.enumCase(Value, "None", FormatStyle::NI_None);
165     IO.enumCase(Value, "Inner", FormatStyle::NI_Inner);
166     IO.enumCase(Value, "All", FormatStyle::NI_All);
167   }
168 };
169 
170 template <> struct ScalarEnumerationTraits<FormatStyle::BracketAlignmentStyle> {
171   static void enumeration(IO &IO, FormatStyle::BracketAlignmentStyle &Value) {
172     IO.enumCase(Value, "Align", FormatStyle::BAS_Align);
173     IO.enumCase(Value, "DontAlign", FormatStyle::BAS_DontAlign);
174     IO.enumCase(Value, "AlwaysBreak", FormatStyle::BAS_AlwaysBreak);
175 
176     // For backward compatibility.
177     IO.enumCase(Value, "true", FormatStyle::BAS_Align);
178     IO.enumCase(Value, "false", FormatStyle::BAS_DontAlign);
179   }
180 };
181 
182 template <> struct ScalarEnumerationTraits<FormatStyle::EscapedNewlineAlignmentStyle> {
183   static void enumeration(IO &IO, FormatStyle::EscapedNewlineAlignmentStyle &Value) {
184     IO.enumCase(Value, "DontAlign", FormatStyle::ENAS_DontAlign);
185     IO.enumCase(Value, "Left", FormatStyle::ENAS_Left);
186     IO.enumCase(Value, "Right", FormatStyle::ENAS_Right);
187 
188     // For backward compatibility.
189     IO.enumCase(Value, "true", FormatStyle::ENAS_Left);
190     IO.enumCase(Value, "false", FormatStyle::ENAS_Right);
191   }
192 };
193 
194 template <> struct ScalarEnumerationTraits<FormatStyle::PointerAlignmentStyle> {
195   static void enumeration(IO &IO, FormatStyle::PointerAlignmentStyle &Value) {
196     IO.enumCase(Value, "Middle", FormatStyle::PAS_Middle);
197     IO.enumCase(Value, "Left", FormatStyle::PAS_Left);
198     IO.enumCase(Value, "Right", FormatStyle::PAS_Right);
199 
200     // For backward compatibility.
201     IO.enumCase(Value, "true", FormatStyle::PAS_Left);
202     IO.enumCase(Value, "false", FormatStyle::PAS_Right);
203   }
204 };
205 
206 template <>
207 struct ScalarEnumerationTraits<FormatStyle::SpaceBeforeParensOptions> {
208   static void enumeration(IO &IO,
209                           FormatStyle::SpaceBeforeParensOptions &Value) {
210     IO.enumCase(Value, "Never", FormatStyle::SBPO_Never);
211     IO.enumCase(Value, "ControlStatements",
212                 FormatStyle::SBPO_ControlStatements);
213     IO.enumCase(Value, "Always", FormatStyle::SBPO_Always);
214 
215     // For backward compatibility.
216     IO.enumCase(Value, "false", FormatStyle::SBPO_Never);
217     IO.enumCase(Value, "true", FormatStyle::SBPO_ControlStatements);
218   }
219 };
220 
221 template <> struct MappingTraits<FormatStyle> {
222   static void mapping(IO &IO, FormatStyle &Style) {
223     // When reading, read the language first, we need it for getPredefinedStyle.
224     IO.mapOptional("Language", Style.Language);
225 
226     if (IO.outputting()) {
227       StringRef StylesArray[] = {"LLVM",    "Google", "Chromium",
228                                  "Mozilla", "WebKit", "GNU"};
229       ArrayRef<StringRef> Styles(StylesArray);
230       for (size_t i = 0, e = Styles.size(); i < e; ++i) {
231         StringRef StyleName(Styles[i]);
232         FormatStyle PredefinedStyle;
233         if (getPredefinedStyle(StyleName, Style.Language, &PredefinedStyle) &&
234             Style == PredefinedStyle) {
235           IO.mapOptional("# BasedOnStyle", StyleName);
236           break;
237         }
238       }
239     } else {
240       StringRef BasedOnStyle;
241       IO.mapOptional("BasedOnStyle", BasedOnStyle);
242       if (!BasedOnStyle.empty()) {
243         FormatStyle::LanguageKind OldLanguage = Style.Language;
244         FormatStyle::LanguageKind Language =
245             ((FormatStyle *)IO.getContext())->Language;
246         if (!getPredefinedStyle(BasedOnStyle, Language, &Style)) {
247           IO.setError(Twine("Unknown value for BasedOnStyle: ", BasedOnStyle));
248           return;
249         }
250         Style.Language = OldLanguage;
251       }
252     }
253 
254     // For backward compatibility.
255     if (!IO.outputting()) {
256       IO.mapOptional("AlignEscapedNewlinesLeft", Style.AlignEscapedNewlines);
257       IO.mapOptional("DerivePointerBinding", Style.DerivePointerAlignment);
258       IO.mapOptional("IndentFunctionDeclarationAfterType",
259                      Style.IndentWrappedFunctionNames);
260       IO.mapOptional("PointerBindsToType", Style.PointerAlignment);
261       IO.mapOptional("SpaceAfterControlStatementKeyword",
262                      Style.SpaceBeforeParens);
263     }
264 
265     IO.mapOptional("AccessModifierOffset", Style.AccessModifierOffset);
266     IO.mapOptional("AlignAfterOpenBracket", Style.AlignAfterOpenBracket);
267     IO.mapOptional("AlignConsecutiveAssignments",
268                    Style.AlignConsecutiveAssignments);
269     IO.mapOptional("AlignConsecutiveDeclarations",
270                    Style.AlignConsecutiveDeclarations);
271     IO.mapOptional("AlignEscapedNewlines", Style.AlignEscapedNewlines);
272     IO.mapOptional("AlignOperands", Style.AlignOperands);
273     IO.mapOptional("AlignTrailingComments", Style.AlignTrailingComments);
274     IO.mapOptional("AllowAllParametersOfDeclarationOnNextLine",
275                    Style.AllowAllParametersOfDeclarationOnNextLine);
276     IO.mapOptional("AllowShortBlocksOnASingleLine",
277                    Style.AllowShortBlocksOnASingleLine);
278     IO.mapOptional("AllowShortCaseLabelsOnASingleLine",
279                    Style.AllowShortCaseLabelsOnASingleLine);
280     IO.mapOptional("AllowShortFunctionsOnASingleLine",
281                    Style.AllowShortFunctionsOnASingleLine);
282     IO.mapOptional("AllowShortIfStatementsOnASingleLine",
283                    Style.AllowShortIfStatementsOnASingleLine);
284     IO.mapOptional("AllowShortLoopsOnASingleLine",
285                    Style.AllowShortLoopsOnASingleLine);
286     IO.mapOptional("AlwaysBreakAfterDefinitionReturnType",
287                    Style.AlwaysBreakAfterDefinitionReturnType);
288     IO.mapOptional("AlwaysBreakAfterReturnType",
289                    Style.AlwaysBreakAfterReturnType);
290     // If AlwaysBreakAfterDefinitionReturnType was specified but
291     // AlwaysBreakAfterReturnType was not, initialize the latter from the
292     // former for backwards compatibility.
293     if (Style.AlwaysBreakAfterDefinitionReturnType != FormatStyle::DRTBS_None &&
294         Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None) {
295       if (Style.AlwaysBreakAfterDefinitionReturnType == FormatStyle::DRTBS_All)
296         Style.AlwaysBreakAfterReturnType = FormatStyle::RTBS_AllDefinitions;
297       else if (Style.AlwaysBreakAfterDefinitionReturnType ==
298                FormatStyle::DRTBS_TopLevel)
299         Style.AlwaysBreakAfterReturnType =
300             FormatStyle::RTBS_TopLevelDefinitions;
301     }
302 
303     IO.mapOptional("AlwaysBreakBeforeMultilineStrings",
304                    Style.AlwaysBreakBeforeMultilineStrings);
305     IO.mapOptional("AlwaysBreakTemplateDeclarations",
306                    Style.AlwaysBreakTemplateDeclarations);
307     IO.mapOptional("BinPackArguments", Style.BinPackArguments);
308     IO.mapOptional("BinPackParameters", Style.BinPackParameters);
309     IO.mapOptional("BraceWrapping", Style.BraceWrapping);
310     IO.mapOptional("BreakBeforeBinaryOperators",
311                    Style.BreakBeforeBinaryOperators);
312     IO.mapOptional("BreakBeforeBraces", Style.BreakBeforeBraces);
313     IO.mapOptional("BreakBeforeInheritanceComma",
314                    Style.BreakBeforeInheritanceComma);
315     IO.mapOptional("BreakBeforeTernaryOperators",
316                    Style.BreakBeforeTernaryOperators);
317 
318     bool BreakConstructorInitializersBeforeComma = false;
319     IO.mapOptional("BreakConstructorInitializersBeforeComma",
320                    BreakConstructorInitializersBeforeComma);
321     IO.mapOptional("BreakConstructorInitializers",
322                    Style.BreakConstructorInitializers);
323     // If BreakConstructorInitializersBeforeComma was specified but
324     // BreakConstructorInitializers was not, initialize the latter from the
325     // former for backwards compatibility.
326     if (BreakConstructorInitializersBeforeComma &&
327         Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeColon)
328       Style.BreakConstructorInitializers = FormatStyle::BCIS_BeforeComma;
329 
330     IO.mapOptional("BreakAfterJavaFieldAnnotations",
331                    Style.BreakAfterJavaFieldAnnotations);
332     IO.mapOptional("BreakStringLiterals", Style.BreakStringLiterals);
333     IO.mapOptional("ColumnLimit", Style.ColumnLimit);
334     IO.mapOptional("CommentPragmas", Style.CommentPragmas);
335     IO.mapOptional("CompactNamespaces", Style.CompactNamespaces);
336     IO.mapOptional("ConstructorInitializerAllOnOneLineOrOnePerLine",
337                    Style.ConstructorInitializerAllOnOneLineOrOnePerLine);
338     IO.mapOptional("ConstructorInitializerIndentWidth",
339                    Style.ConstructorInitializerIndentWidth);
340     IO.mapOptional("ContinuationIndentWidth", Style.ContinuationIndentWidth);
341     IO.mapOptional("Cpp11BracedListStyle", Style.Cpp11BracedListStyle);
342     IO.mapOptional("DerivePointerAlignment", Style.DerivePointerAlignment);
343     IO.mapOptional("DisableFormat", Style.DisableFormat);
344     IO.mapOptional("ExperimentalAutoDetectBinPacking",
345                    Style.ExperimentalAutoDetectBinPacking);
346     IO.mapOptional("FixNamespaceComments", Style.FixNamespaceComments);
347     IO.mapOptional("ForEachMacros", Style.ForEachMacros);
348     IO.mapOptional("IncludeCategories", Style.IncludeCategories);
349     IO.mapOptional("IncludeIsMainRegex", Style.IncludeIsMainRegex);
350     IO.mapOptional("IndentCaseLabels", Style.IndentCaseLabels);
351     IO.mapOptional("IndentWidth", Style.IndentWidth);
352     IO.mapOptional("IndentWrappedFunctionNames",
353                    Style.IndentWrappedFunctionNames);
354     IO.mapOptional("JavaScriptQuotes", Style.JavaScriptQuotes);
355     IO.mapOptional("JavaScriptWrapImports", Style.JavaScriptWrapImports);
356     IO.mapOptional("KeepEmptyLinesAtTheStartOfBlocks",
357                    Style.KeepEmptyLinesAtTheStartOfBlocks);
358     IO.mapOptional("MacroBlockBegin", Style.MacroBlockBegin);
359     IO.mapOptional("MacroBlockEnd", Style.MacroBlockEnd);
360     IO.mapOptional("MaxEmptyLinesToKeep", Style.MaxEmptyLinesToKeep);
361     IO.mapOptional("NamespaceIndentation", Style.NamespaceIndentation);
362     IO.mapOptional("ObjCBlockIndentWidth", Style.ObjCBlockIndentWidth);
363     IO.mapOptional("ObjCSpaceAfterProperty", Style.ObjCSpaceAfterProperty);
364     IO.mapOptional("ObjCSpaceBeforeProtocolList",
365                    Style.ObjCSpaceBeforeProtocolList);
366     IO.mapOptional("PenaltyBreakAssignment",
367                    Style.PenaltyBreakAssignment);
368     IO.mapOptional("PenaltyBreakBeforeFirstCallParameter",
369                    Style.PenaltyBreakBeforeFirstCallParameter);
370     IO.mapOptional("PenaltyBreakComment", Style.PenaltyBreakComment);
371     IO.mapOptional("PenaltyBreakFirstLessLess",
372                    Style.PenaltyBreakFirstLessLess);
373     IO.mapOptional("PenaltyBreakString", Style.PenaltyBreakString);
374     IO.mapOptional("PenaltyExcessCharacter", Style.PenaltyExcessCharacter);
375     IO.mapOptional("PenaltyReturnTypeOnItsOwnLine",
376                    Style.PenaltyReturnTypeOnItsOwnLine);
377     IO.mapOptional("PointerAlignment", Style.PointerAlignment);
378     IO.mapOptional("ReflowComments", Style.ReflowComments);
379     IO.mapOptional("SortIncludes", Style.SortIncludes);
380     IO.mapOptional("SpaceAfterCStyleCast", Style.SpaceAfterCStyleCast);
381     IO.mapOptional("SpaceAfterTemplateKeyword", Style.SpaceAfterTemplateKeyword);
382     IO.mapOptional("SpaceBeforeAssignmentOperators",
383                    Style.SpaceBeforeAssignmentOperators);
384     IO.mapOptional("SpaceBeforeParens", Style.SpaceBeforeParens);
385     IO.mapOptional("SpaceInEmptyParentheses", Style.SpaceInEmptyParentheses);
386     IO.mapOptional("SpacesBeforeTrailingComments",
387                    Style.SpacesBeforeTrailingComments);
388     IO.mapOptional("SpacesInAngles", Style.SpacesInAngles);
389     IO.mapOptional("SpacesInContainerLiterals",
390                    Style.SpacesInContainerLiterals);
391     IO.mapOptional("SpacesInCStyleCastParentheses",
392                    Style.SpacesInCStyleCastParentheses);
393     IO.mapOptional("SpacesInParentheses", Style.SpacesInParentheses);
394     IO.mapOptional("SpacesInSquareBrackets", Style.SpacesInSquareBrackets);
395     IO.mapOptional("Standard", Style.Standard);
396     IO.mapOptional("TabWidth", Style.TabWidth);
397     IO.mapOptional("UseTab", Style.UseTab);
398   }
399 };
400 
401 template <> struct MappingTraits<FormatStyle::BraceWrappingFlags> {
402   static void mapping(IO &IO, FormatStyle::BraceWrappingFlags &Wrapping) {
403     IO.mapOptional("AfterClass", Wrapping.AfterClass);
404     IO.mapOptional("AfterControlStatement", Wrapping.AfterControlStatement);
405     IO.mapOptional("AfterEnum", Wrapping.AfterEnum);
406     IO.mapOptional("AfterFunction", Wrapping.AfterFunction);
407     IO.mapOptional("AfterNamespace", Wrapping.AfterNamespace);
408     IO.mapOptional("AfterObjCDeclaration", Wrapping.AfterObjCDeclaration);
409     IO.mapOptional("AfterStruct", Wrapping.AfterStruct);
410     IO.mapOptional("AfterUnion", Wrapping.AfterUnion);
411     IO.mapOptional("BeforeCatch", Wrapping.BeforeCatch);
412     IO.mapOptional("BeforeElse", Wrapping.BeforeElse);
413     IO.mapOptional("IndentBraces", Wrapping.IndentBraces);
414     IO.mapOptional("SplitEmptyFunctionBody", Wrapping.SplitEmptyFunctionBody);
415   }
416 };
417 
418 template <> struct MappingTraits<FormatStyle::IncludeCategory> {
419   static void mapping(IO &IO, FormatStyle::IncludeCategory &Category) {
420     IO.mapOptional("Regex", Category.Regex);
421     IO.mapOptional("Priority", Category.Priority);
422   }
423 };
424 
425 // Allows to read vector<FormatStyle> while keeping default values.
426 // IO.getContext() should contain a pointer to the FormatStyle structure, that
427 // will be used to get default values for missing keys.
428 // If the first element has no Language specified, it will be treated as the
429 // default one for the following elements.
430 template <> struct DocumentListTraits<std::vector<FormatStyle>> {
431   static size_t size(IO &IO, std::vector<FormatStyle> &Seq) {
432     return Seq.size();
433   }
434   static FormatStyle &element(IO &IO, std::vector<FormatStyle> &Seq,
435                               size_t Index) {
436     if (Index >= Seq.size()) {
437       assert(Index == Seq.size());
438       FormatStyle Template;
439       if (Seq.size() > 0 && Seq[0].Language == FormatStyle::LK_None) {
440         Template = Seq[0];
441       } else {
442         Template = *((const FormatStyle *)IO.getContext());
443         Template.Language = FormatStyle::LK_None;
444       }
445       Seq.resize(Index + 1, Template);
446     }
447     return Seq[Index];
448   }
449 };
450 } // namespace yaml
451 } // namespace llvm
452 
453 namespace clang {
454 namespace format {
455 
456 const std::error_category &getParseCategory() {
457   static ParseErrorCategory C;
458   return C;
459 }
460 std::error_code make_error_code(ParseError e) {
461   return std::error_code(static_cast<int>(e), getParseCategory());
462 }
463 
464 inline llvm::Error make_string_error(const llvm::Twine &Message) {
465   return llvm::make_error<llvm::StringError>(Message,
466                                              llvm::inconvertibleErrorCode());
467 }
468 
469 const char *ParseErrorCategory::name() const noexcept {
470   return "clang-format.parse_error";
471 }
472 
473 std::string ParseErrorCategory::message(int EV) const {
474   switch (static_cast<ParseError>(EV)) {
475   case ParseError::Success:
476     return "Success";
477   case ParseError::Error:
478     return "Invalid argument";
479   case ParseError::Unsuitable:
480     return "Unsuitable";
481   }
482   llvm_unreachable("unexpected parse error");
483 }
484 
485 static FormatStyle expandPresets(const FormatStyle &Style) {
486   if (Style.BreakBeforeBraces == FormatStyle::BS_Custom)
487     return Style;
488   FormatStyle Expanded = Style;
489   Expanded.BraceWrapping = {false, false, false, false, false, false,
490                             false, false, false, false, false, true};
491   switch (Style.BreakBeforeBraces) {
492   case FormatStyle::BS_Linux:
493     Expanded.BraceWrapping.AfterClass = true;
494     Expanded.BraceWrapping.AfterFunction = true;
495     Expanded.BraceWrapping.AfterNamespace = true;
496     break;
497   case FormatStyle::BS_Mozilla:
498     Expanded.BraceWrapping.AfterClass = true;
499     Expanded.BraceWrapping.AfterEnum = true;
500     Expanded.BraceWrapping.AfterFunction = true;
501     Expanded.BraceWrapping.AfterStruct = true;
502     Expanded.BraceWrapping.AfterUnion = true;
503     Expanded.BraceWrapping.SplitEmptyFunctionBody = false;
504     break;
505   case FormatStyle::BS_Stroustrup:
506     Expanded.BraceWrapping.AfterFunction = true;
507     Expanded.BraceWrapping.BeforeCatch = true;
508     Expanded.BraceWrapping.BeforeElse = true;
509     break;
510   case FormatStyle::BS_Allman:
511     Expanded.BraceWrapping.AfterClass = true;
512     Expanded.BraceWrapping.AfterControlStatement = true;
513     Expanded.BraceWrapping.AfterEnum = true;
514     Expanded.BraceWrapping.AfterFunction = true;
515     Expanded.BraceWrapping.AfterNamespace = true;
516     Expanded.BraceWrapping.AfterObjCDeclaration = true;
517     Expanded.BraceWrapping.AfterStruct = true;
518     Expanded.BraceWrapping.BeforeCatch = true;
519     Expanded.BraceWrapping.BeforeElse = true;
520     break;
521   case FormatStyle::BS_GNU:
522     Expanded.BraceWrapping = {true, true, true, true, true, true,
523                               true, true, true, true, true, true};
524     break;
525   case FormatStyle::BS_WebKit:
526     Expanded.BraceWrapping.AfterFunction = true;
527     break;
528   default:
529     break;
530   }
531   return Expanded;
532 }
533 
534 FormatStyle getLLVMStyle() {
535   FormatStyle LLVMStyle;
536   LLVMStyle.Language = FormatStyle::LK_Cpp;
537   LLVMStyle.AccessModifierOffset = -2;
538   LLVMStyle.AlignEscapedNewlines = FormatStyle::ENAS_Right;
539   LLVMStyle.AlignAfterOpenBracket = FormatStyle::BAS_Align;
540   LLVMStyle.AlignOperands = true;
541   LLVMStyle.AlignTrailingComments = true;
542   LLVMStyle.AlignConsecutiveAssignments = false;
543   LLVMStyle.AlignConsecutiveDeclarations = false;
544   LLVMStyle.AllowAllParametersOfDeclarationOnNextLine = true;
545   LLVMStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_All;
546   LLVMStyle.AllowShortBlocksOnASingleLine = false;
547   LLVMStyle.AllowShortCaseLabelsOnASingleLine = false;
548   LLVMStyle.AllowShortIfStatementsOnASingleLine = false;
549   LLVMStyle.AllowShortLoopsOnASingleLine = false;
550   LLVMStyle.AlwaysBreakAfterReturnType = FormatStyle::RTBS_None;
551   LLVMStyle.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_None;
552   LLVMStyle.AlwaysBreakBeforeMultilineStrings = false;
553   LLVMStyle.AlwaysBreakTemplateDeclarations = false;
554   LLVMStyle.BinPackArguments = true;
555   LLVMStyle.BinPackParameters = true;
556   LLVMStyle.BreakBeforeBinaryOperators = FormatStyle::BOS_None;
557   LLVMStyle.BreakBeforeTernaryOperators = true;
558   LLVMStyle.BreakBeforeBraces = FormatStyle::BS_Attach;
559   LLVMStyle.BraceWrapping = {false, false, false, false, false, false,
560                              false, false, false, false, false, true};
561   LLVMStyle.BreakAfterJavaFieldAnnotations = false;
562   LLVMStyle.BreakConstructorInitializers = FormatStyle::BCIS_BeforeColon;
563   LLVMStyle.BreakBeforeInheritanceComma = false;
564   LLVMStyle.BreakStringLiterals = true;
565   LLVMStyle.ColumnLimit = 80;
566   LLVMStyle.CommentPragmas = "^ IWYU pragma:";
567   LLVMStyle.CompactNamespaces = false;
568   LLVMStyle.ConstructorInitializerAllOnOneLineOrOnePerLine = false;
569   LLVMStyle.ConstructorInitializerIndentWidth = 4;
570   LLVMStyle.ContinuationIndentWidth = 4;
571   LLVMStyle.Cpp11BracedListStyle = true;
572   LLVMStyle.DerivePointerAlignment = false;
573   LLVMStyle.ExperimentalAutoDetectBinPacking = false;
574   LLVMStyle.FixNamespaceComments = true;
575   LLVMStyle.ForEachMacros.push_back("foreach");
576   LLVMStyle.ForEachMacros.push_back("Q_FOREACH");
577   LLVMStyle.ForEachMacros.push_back("BOOST_FOREACH");
578   LLVMStyle.IncludeCategories = {{"^\"(llvm|llvm-c|clang|clang-c)/", 2},
579                                  {"^(<|\"(gtest|isl|json)/)", 3},
580                                  {".*", 1}};
581   LLVMStyle.IncludeIsMainRegex = "$";
582   LLVMStyle.IndentCaseLabels = false;
583   LLVMStyle.IndentWrappedFunctionNames = false;
584   LLVMStyle.IndentWidth = 2;
585   LLVMStyle.JavaScriptQuotes = FormatStyle::JSQS_Leave;
586   LLVMStyle.JavaScriptWrapImports = true;
587   LLVMStyle.TabWidth = 8;
588   LLVMStyle.MaxEmptyLinesToKeep = 1;
589   LLVMStyle.KeepEmptyLinesAtTheStartOfBlocks = true;
590   LLVMStyle.NamespaceIndentation = FormatStyle::NI_None;
591   LLVMStyle.ObjCBlockIndentWidth = 2;
592   LLVMStyle.ObjCSpaceAfterProperty = false;
593   LLVMStyle.ObjCSpaceBeforeProtocolList = true;
594   LLVMStyle.PointerAlignment = FormatStyle::PAS_Right;
595   LLVMStyle.SpacesBeforeTrailingComments = 1;
596   LLVMStyle.Standard = FormatStyle::LS_Cpp11;
597   LLVMStyle.UseTab = FormatStyle::UT_Never;
598   LLVMStyle.ReflowComments = true;
599   LLVMStyle.SpacesInParentheses = false;
600   LLVMStyle.SpacesInSquareBrackets = false;
601   LLVMStyle.SpaceInEmptyParentheses = false;
602   LLVMStyle.SpacesInContainerLiterals = true;
603   LLVMStyle.SpacesInCStyleCastParentheses = false;
604   LLVMStyle.SpaceAfterCStyleCast = false;
605   LLVMStyle.SpaceAfterTemplateKeyword = true;
606   LLVMStyle.SpaceBeforeParens = FormatStyle::SBPO_ControlStatements;
607   LLVMStyle.SpaceBeforeAssignmentOperators = true;
608   LLVMStyle.SpacesInAngles = false;
609 
610   LLVMStyle.PenaltyBreakAssignment = prec::Assignment;
611   LLVMStyle.PenaltyBreakComment = 300;
612   LLVMStyle.PenaltyBreakFirstLessLess = 120;
613   LLVMStyle.PenaltyBreakString = 1000;
614   LLVMStyle.PenaltyExcessCharacter = 1000000;
615   LLVMStyle.PenaltyReturnTypeOnItsOwnLine = 60;
616   LLVMStyle.PenaltyBreakBeforeFirstCallParameter = 19;
617 
618   LLVMStyle.DisableFormat = false;
619   LLVMStyle.SortIncludes = true;
620 
621   return LLVMStyle;
622 }
623 
624 FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
625   FormatStyle GoogleStyle = getLLVMStyle();
626   GoogleStyle.Language = Language;
627 
628   GoogleStyle.AccessModifierOffset = -1;
629   GoogleStyle.AlignEscapedNewlines = FormatStyle::ENAS_Left;
630   GoogleStyle.AllowShortIfStatementsOnASingleLine = true;
631   GoogleStyle.AllowShortLoopsOnASingleLine = true;
632   GoogleStyle.AlwaysBreakBeforeMultilineStrings = true;
633   GoogleStyle.AlwaysBreakTemplateDeclarations = true;
634   GoogleStyle.ConstructorInitializerAllOnOneLineOrOnePerLine = true;
635   GoogleStyle.DerivePointerAlignment = true;
636   GoogleStyle.IncludeCategories = {{"^<.*\\.h>", 1}, {"^<.*", 2}, {".*", 3}};
637   GoogleStyle.IncludeIsMainRegex = "([-_](test|unittest))?$";
638   GoogleStyle.IndentCaseLabels = true;
639   GoogleStyle.KeepEmptyLinesAtTheStartOfBlocks = false;
640   GoogleStyle.ObjCSpaceAfterProperty = false;
641   GoogleStyle.ObjCSpaceBeforeProtocolList = false;
642   GoogleStyle.PointerAlignment = FormatStyle::PAS_Left;
643   GoogleStyle.SpacesBeforeTrailingComments = 2;
644   GoogleStyle.Standard = FormatStyle::LS_Auto;
645 
646   GoogleStyle.PenaltyReturnTypeOnItsOwnLine = 200;
647   GoogleStyle.PenaltyBreakBeforeFirstCallParameter = 1;
648 
649   if (Language == FormatStyle::LK_Java) {
650     GoogleStyle.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
651     GoogleStyle.AlignOperands = false;
652     GoogleStyle.AlignTrailingComments = false;
653     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Empty;
654     GoogleStyle.AllowShortIfStatementsOnASingleLine = false;
655     GoogleStyle.AlwaysBreakBeforeMultilineStrings = false;
656     GoogleStyle.BreakBeforeBinaryOperators = FormatStyle::BOS_NonAssignment;
657     GoogleStyle.ColumnLimit = 100;
658     GoogleStyle.SpaceAfterCStyleCast = true;
659     GoogleStyle.SpacesBeforeTrailingComments = 1;
660   } else if (Language == FormatStyle::LK_JavaScript) {
661     GoogleStyle.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
662     GoogleStyle.AlignOperands = false;
663     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Empty;
664     GoogleStyle.AlwaysBreakBeforeMultilineStrings = false;
665     GoogleStyle.BreakBeforeTernaryOperators = false;
666     // taze:, triple slash directives (`/// <...`), @tag followed by { for a lot
667     // of JSDoc tags, and @see, which is commonly followed by overlong URLs.
668     GoogleStyle.CommentPragmas =
669         "(taze:|^/[ \t]*<|(@[A-Za-z_0-9-]+[ \\t]*{)|@see)";
670     GoogleStyle.MaxEmptyLinesToKeep = 3;
671     GoogleStyle.NamespaceIndentation = FormatStyle::NI_All;
672     GoogleStyle.SpacesInContainerLiterals = false;
673     GoogleStyle.JavaScriptQuotes = FormatStyle::JSQS_Single;
674     GoogleStyle.JavaScriptWrapImports = false;
675   } else if (Language == FormatStyle::LK_Proto) {
676     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_None;
677     GoogleStyle.SpacesInContainerLiterals = false;
678   } else if (Language == FormatStyle::LK_ObjC) {
679     GoogleStyle.ColumnLimit = 100;
680   }
681 
682   return GoogleStyle;
683 }
684 
685 FormatStyle getChromiumStyle(FormatStyle::LanguageKind Language) {
686   FormatStyle ChromiumStyle = getGoogleStyle(Language);
687   if (Language == FormatStyle::LK_Java) {
688     ChromiumStyle.AllowShortIfStatementsOnASingleLine = true;
689     ChromiumStyle.BreakAfterJavaFieldAnnotations = true;
690     ChromiumStyle.ContinuationIndentWidth = 8;
691     ChromiumStyle.IndentWidth = 4;
692   } else if (Language == FormatStyle::LK_JavaScript) {
693     ChromiumStyle.AllowShortIfStatementsOnASingleLine = false;
694     ChromiumStyle.AllowShortLoopsOnASingleLine = false;
695   } else {
696     ChromiumStyle.AllowAllParametersOfDeclarationOnNextLine = false;
697     ChromiumStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Inline;
698     ChromiumStyle.AllowShortIfStatementsOnASingleLine = false;
699     ChromiumStyle.AllowShortLoopsOnASingleLine = false;
700     ChromiumStyle.BinPackParameters = false;
701     ChromiumStyle.DerivePointerAlignment = false;
702     if (Language == FormatStyle::LK_ObjC)
703       ChromiumStyle.ColumnLimit = 80;
704   }
705   return ChromiumStyle;
706 }
707 
708 FormatStyle getMozillaStyle() {
709   FormatStyle MozillaStyle = getLLVMStyle();
710   MozillaStyle.AllowAllParametersOfDeclarationOnNextLine = false;
711   MozillaStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Inline;
712   MozillaStyle.AlwaysBreakAfterReturnType =
713       FormatStyle::RTBS_TopLevel;
714   MozillaStyle.AlwaysBreakAfterDefinitionReturnType =
715       FormatStyle::DRTBS_TopLevel;
716   MozillaStyle.AlwaysBreakTemplateDeclarations = true;
717   MozillaStyle.BinPackParameters = false;
718   MozillaStyle.BinPackArguments = false;
719   MozillaStyle.BreakBeforeBraces = FormatStyle::BS_Mozilla;
720   MozillaStyle.BreakConstructorInitializers = FormatStyle::BCIS_BeforeComma;
721   MozillaStyle.BreakBeforeInheritanceComma = true;
722   MozillaStyle.ConstructorInitializerIndentWidth = 2;
723   MozillaStyle.ContinuationIndentWidth = 2;
724   MozillaStyle.Cpp11BracedListStyle = false;
725   MozillaStyle.FixNamespaceComments = false;
726   MozillaStyle.IndentCaseLabels = true;
727   MozillaStyle.ObjCSpaceAfterProperty = true;
728   MozillaStyle.ObjCSpaceBeforeProtocolList = false;
729   MozillaStyle.PenaltyReturnTypeOnItsOwnLine = 200;
730   MozillaStyle.PointerAlignment = FormatStyle::PAS_Left;
731   MozillaStyle.SpaceAfterTemplateKeyword = false;
732   return MozillaStyle;
733 }
734 
735 FormatStyle getWebKitStyle() {
736   FormatStyle Style = getLLVMStyle();
737   Style.AccessModifierOffset = -4;
738   Style.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
739   Style.AlignOperands = false;
740   Style.AlignTrailingComments = false;
741   Style.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
742   Style.BreakBeforeBraces = FormatStyle::BS_WebKit;
743   Style.BreakConstructorInitializers = FormatStyle::BCIS_BeforeComma;
744   Style.Cpp11BracedListStyle = false;
745   Style.ColumnLimit = 0;
746   Style.FixNamespaceComments = false;
747   Style.IndentWidth = 4;
748   Style.NamespaceIndentation = FormatStyle::NI_Inner;
749   Style.ObjCBlockIndentWidth = 4;
750   Style.ObjCSpaceAfterProperty = true;
751   Style.PointerAlignment = FormatStyle::PAS_Left;
752   return Style;
753 }
754 
755 FormatStyle getGNUStyle() {
756   FormatStyle Style = getLLVMStyle();
757   Style.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_All;
758   Style.AlwaysBreakAfterReturnType = FormatStyle::RTBS_AllDefinitions;
759   Style.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
760   Style.BreakBeforeBraces = FormatStyle::BS_GNU;
761   Style.BreakBeforeTernaryOperators = true;
762   Style.Cpp11BracedListStyle = false;
763   Style.ColumnLimit = 79;
764   Style.FixNamespaceComments = false;
765   Style.SpaceBeforeParens = FormatStyle::SBPO_Always;
766   Style.Standard = FormatStyle::LS_Cpp03;
767   return Style;
768 }
769 
770 FormatStyle getNoStyle() {
771   FormatStyle NoStyle = getLLVMStyle();
772   NoStyle.DisableFormat = true;
773   NoStyle.SortIncludes = false;
774   return NoStyle;
775 }
776 
777 bool getPredefinedStyle(StringRef Name, FormatStyle::LanguageKind Language,
778                         FormatStyle *Style) {
779   if (Name.equals_lower("llvm")) {
780     *Style = getLLVMStyle();
781   } else if (Name.equals_lower("chromium")) {
782     *Style = getChromiumStyle(Language);
783   } else if (Name.equals_lower("mozilla")) {
784     *Style = getMozillaStyle();
785   } else if (Name.equals_lower("google")) {
786     *Style = getGoogleStyle(Language);
787   } else if (Name.equals_lower("webkit")) {
788     *Style = getWebKitStyle();
789   } else if (Name.equals_lower("gnu")) {
790     *Style = getGNUStyle();
791   } else if (Name.equals_lower("none")) {
792     *Style = getNoStyle();
793   } else {
794     return false;
795   }
796 
797   Style->Language = Language;
798   return true;
799 }
800 
801 std::error_code parseConfiguration(StringRef Text, FormatStyle *Style) {
802   assert(Style);
803   FormatStyle::LanguageKind Language = Style->Language;
804   assert(Language != FormatStyle::LK_None);
805   if (Text.trim().empty())
806     return make_error_code(ParseError::Error);
807 
808   std::vector<FormatStyle> Styles;
809   llvm::yaml::Input Input(Text);
810   // DocumentListTraits<vector<FormatStyle>> uses the context to get default
811   // values for the fields, keys for which are missing from the configuration.
812   // Mapping also uses the context to get the language to find the correct
813   // base style.
814   Input.setContext(Style);
815   Input >> Styles;
816   if (Input.error())
817     return Input.error();
818 
819   for (unsigned i = 0; i < Styles.size(); ++i) {
820     // Ensures that only the first configuration can skip the Language option.
821     if (Styles[i].Language == FormatStyle::LK_None && i != 0)
822       return make_error_code(ParseError::Error);
823     // Ensure that each language is configured at most once.
824     for (unsigned j = 0; j < i; ++j) {
825       if (Styles[i].Language == Styles[j].Language) {
826         DEBUG(llvm::dbgs()
827               << "Duplicate languages in the config file on positions " << j
828               << " and " << i << "\n");
829         return make_error_code(ParseError::Error);
830       }
831     }
832   }
833   // Look for a suitable configuration starting from the end, so we can
834   // find the configuration for the specific language first, and the default
835   // configuration (which can only be at slot 0) after it.
836   for (int i = Styles.size() - 1; i >= 0; --i) {
837     if (Styles[i].Language == Language ||
838         Styles[i].Language == FormatStyle::LK_None) {
839       *Style = Styles[i];
840       Style->Language = Language;
841       return make_error_code(ParseError::Success);
842     }
843   }
844   return make_error_code(ParseError::Unsuitable);
845 }
846 
847 std::string configurationAsText(const FormatStyle &Style) {
848   std::string Text;
849   llvm::raw_string_ostream Stream(Text);
850   llvm::yaml::Output Output(Stream);
851   // We use the same mapping method for input and output, so we need a non-const
852   // reference here.
853   FormatStyle NonConstStyle = expandPresets(Style);
854   Output << NonConstStyle;
855   return Stream.str();
856 }
857 
858 namespace {
859 
860 class JavaScriptRequoter : public TokenAnalyzer {
861 public:
862   JavaScriptRequoter(const Environment &Env, const FormatStyle &Style)
863       : TokenAnalyzer(Env, Style) {}
864 
865   tooling::Replacements
866   analyze(TokenAnnotator &Annotator,
867           SmallVectorImpl<AnnotatedLine *> &AnnotatedLines,
868           FormatTokenLexer &Tokens) override {
869     AffectedRangeMgr.computeAffectedLines(AnnotatedLines.begin(),
870                                           AnnotatedLines.end());
871     tooling::Replacements Result;
872     requoteJSStringLiteral(AnnotatedLines, Result);
873     return Result;
874   }
875 
876 private:
877   // Replaces double/single-quoted string literal as appropriate, re-escaping
878   // the contents in the process.
879   void requoteJSStringLiteral(SmallVectorImpl<AnnotatedLine *> &Lines,
880                               tooling::Replacements &Result) {
881     for (AnnotatedLine *Line : Lines) {
882       requoteJSStringLiteral(Line->Children, Result);
883       if (!Line->Affected)
884         continue;
885       for (FormatToken *FormatTok = Line->First; FormatTok;
886            FormatTok = FormatTok->Next) {
887         StringRef Input = FormatTok->TokenText;
888         if (FormatTok->Finalized || !FormatTok->isStringLiteral() ||
889             // NB: testing for not starting with a double quote to avoid
890             // breaking `template strings`.
891             (Style.JavaScriptQuotes == FormatStyle::JSQS_Single &&
892              !Input.startswith("\"")) ||
893             (Style.JavaScriptQuotes == FormatStyle::JSQS_Double &&
894              !Input.startswith("\'")))
895           continue;
896 
897         // Change start and end quote.
898         bool IsSingle = Style.JavaScriptQuotes == FormatStyle::JSQS_Single;
899         SourceLocation Start = FormatTok->Tok.getLocation();
900         auto Replace = [&](SourceLocation Start, unsigned Length,
901                            StringRef ReplacementText) {
902           auto Err = Result.add(tooling::Replacement(
903               Env.getSourceManager(), Start, Length, ReplacementText));
904           // FIXME: handle error. For now, print error message and skip the
905           // replacement for release version.
906           if (Err) {
907             llvm::errs() << llvm::toString(std::move(Err)) << "\n";
908             assert(false);
909           }
910         };
911         Replace(Start, 1, IsSingle ? "'" : "\"");
912         Replace(FormatTok->Tok.getEndLoc().getLocWithOffset(-1), 1,
913                 IsSingle ? "'" : "\"");
914 
915         // Escape internal quotes.
916         bool Escaped = false;
917         for (size_t i = 1; i < Input.size() - 1; i++) {
918           switch (Input[i]) {
919           case '\\':
920             if (!Escaped && i + 1 < Input.size() &&
921                 ((IsSingle && Input[i + 1] == '"') ||
922                  (!IsSingle && Input[i + 1] == '\''))) {
923               // Remove this \, it's escaping a " or ' that no longer needs
924               // escaping
925               Replace(Start.getLocWithOffset(i), 1, "");
926               continue;
927             }
928             Escaped = !Escaped;
929             break;
930           case '\"':
931           case '\'':
932             if (!Escaped && IsSingle == (Input[i] == '\'')) {
933               // Escape the quote.
934               Replace(Start.getLocWithOffset(i), 0, "\\");
935             }
936             Escaped = false;
937             break;
938           default:
939             Escaped = false;
940             break;
941           }
942         }
943       }
944     }
945   }
946 };
947 
948 class Formatter : public TokenAnalyzer {
949 public:
950   Formatter(const Environment &Env, const FormatStyle &Style,
951             FormattingAttemptStatus *Status)
952       : TokenAnalyzer(Env, Style), Status(Status) {}
953 
954   tooling::Replacements
955   analyze(TokenAnnotator &Annotator,
956           SmallVectorImpl<AnnotatedLine *> &AnnotatedLines,
957           FormatTokenLexer &Tokens) override {
958     tooling::Replacements Result;
959     deriveLocalStyle(AnnotatedLines);
960     AffectedRangeMgr.computeAffectedLines(AnnotatedLines.begin(),
961                                           AnnotatedLines.end());
962     for (unsigned i = 0, e = AnnotatedLines.size(); i != e; ++i) {
963       Annotator.calculateFormattingInformation(*AnnotatedLines[i]);
964     }
965     Annotator.setCommentLineLevels(AnnotatedLines);
966 
967     WhitespaceManager Whitespaces(
968         Env.getSourceManager(), Style,
969         inputUsesCRLF(Env.getSourceManager().getBufferData(Env.getFileID())));
970     ContinuationIndenter Indenter(Style, Tokens.getKeywords(),
971                                   Env.getSourceManager(), Whitespaces, Encoding,
972                                   BinPackInconclusiveFunctions);
973     UnwrappedLineFormatter(&Indenter, &Whitespaces, Style, Tokens.getKeywords(),
974                            Env.getSourceManager(), Status)
975         .format(AnnotatedLines);
976     for (const auto &R : Whitespaces.generateReplacements())
977       if (Result.add(R))
978         return Result;
979     return Result;
980   }
981 
982 private:
983 
984   static bool inputUsesCRLF(StringRef Text) {
985     return Text.count('\r') * 2 > Text.count('\n');
986   }
987 
988   bool
989   hasCpp03IncompatibleFormat(const SmallVectorImpl<AnnotatedLine *> &Lines) {
990     for (const AnnotatedLine *Line : Lines) {
991       if (hasCpp03IncompatibleFormat(Line->Children))
992         return true;
993       for (FormatToken *Tok = Line->First->Next; Tok; Tok = Tok->Next) {
994         if (Tok->WhitespaceRange.getBegin() == Tok->WhitespaceRange.getEnd()) {
995           if (Tok->is(tok::coloncolon) && Tok->Previous->is(TT_TemplateOpener))
996             return true;
997           if (Tok->is(TT_TemplateCloser) &&
998               Tok->Previous->is(TT_TemplateCloser))
999             return true;
1000         }
1001       }
1002     }
1003     return false;
1004   }
1005 
1006   int countVariableAlignments(const SmallVectorImpl<AnnotatedLine *> &Lines) {
1007     int AlignmentDiff = 0;
1008     for (const AnnotatedLine *Line : Lines) {
1009       AlignmentDiff += countVariableAlignments(Line->Children);
1010       for (FormatToken *Tok = Line->First; Tok && Tok->Next; Tok = Tok->Next) {
1011         if (!Tok->is(TT_PointerOrReference))
1012           continue;
1013         bool SpaceBefore =
1014             Tok->WhitespaceRange.getBegin() != Tok->WhitespaceRange.getEnd();
1015         bool SpaceAfter = Tok->Next->WhitespaceRange.getBegin() !=
1016                           Tok->Next->WhitespaceRange.getEnd();
1017         if (SpaceBefore && !SpaceAfter)
1018           ++AlignmentDiff;
1019         if (!SpaceBefore && SpaceAfter)
1020           --AlignmentDiff;
1021       }
1022     }
1023     return AlignmentDiff;
1024   }
1025 
1026   void
1027   deriveLocalStyle(const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
1028     bool HasBinPackedFunction = false;
1029     bool HasOnePerLineFunction = false;
1030     for (unsigned i = 0, e = AnnotatedLines.size(); i != e; ++i) {
1031       if (!AnnotatedLines[i]->First->Next)
1032         continue;
1033       FormatToken *Tok = AnnotatedLines[i]->First->Next;
1034       while (Tok->Next) {
1035         if (Tok->PackingKind == PPK_BinPacked)
1036           HasBinPackedFunction = true;
1037         if (Tok->PackingKind == PPK_OnePerLine)
1038           HasOnePerLineFunction = true;
1039 
1040         Tok = Tok->Next;
1041       }
1042     }
1043     if (Style.DerivePointerAlignment)
1044       Style.PointerAlignment = countVariableAlignments(AnnotatedLines) <= 0
1045                                    ? FormatStyle::PAS_Left
1046                                    : FormatStyle::PAS_Right;
1047     if (Style.Standard == FormatStyle::LS_Auto)
1048       Style.Standard = hasCpp03IncompatibleFormat(AnnotatedLines)
1049                            ? FormatStyle::LS_Cpp11
1050                            : FormatStyle::LS_Cpp03;
1051     BinPackInconclusiveFunctions =
1052         HasBinPackedFunction || !HasOnePerLineFunction;
1053   }
1054 
1055   bool BinPackInconclusiveFunctions;
1056   FormattingAttemptStatus *Status;
1057 };
1058 
1059 // This class clean up the erroneous/redundant code around the given ranges in
1060 // file.
1061 class Cleaner : public TokenAnalyzer {
1062 public:
1063   Cleaner(const Environment &Env, const FormatStyle &Style)
1064       : TokenAnalyzer(Env, Style),
1065         DeletedTokens(FormatTokenLess(Env.getSourceManager())) {}
1066 
1067   // FIXME: eliminate unused parameters.
1068   tooling::Replacements
1069   analyze(TokenAnnotator &Annotator,
1070           SmallVectorImpl<AnnotatedLine *> &AnnotatedLines,
1071           FormatTokenLexer &Tokens) override {
1072     // FIXME: in the current implementation the granularity of affected range
1073     // is an annotated line. However, this is not sufficient. Furthermore,
1074     // redundant code introduced by replacements does not necessarily
1075     // intercept with ranges of replacements that result in the redundancy.
1076     // To determine if some redundant code is actually introduced by
1077     // replacements(e.g. deletions), we need to come up with a more
1078     // sophisticated way of computing affected ranges.
1079     AffectedRangeMgr.computeAffectedLines(AnnotatedLines.begin(),
1080                                           AnnotatedLines.end());
1081 
1082     checkEmptyNamespace(AnnotatedLines);
1083 
1084     for (auto &Line : AnnotatedLines) {
1085       if (Line->Affected) {
1086         cleanupRight(Line->First, tok::comma, tok::comma);
1087         cleanupRight(Line->First, TT_CtorInitializerColon, tok::comma);
1088         cleanupRight(Line->First, tok::l_paren, tok::comma);
1089         cleanupLeft(Line->First, tok::comma, tok::r_paren);
1090         cleanupLeft(Line->First, TT_CtorInitializerComma, tok::l_brace);
1091         cleanupLeft(Line->First, TT_CtorInitializerColon, tok::l_brace);
1092         cleanupLeft(Line->First, TT_CtorInitializerColon, tok::equal);
1093       }
1094     }
1095 
1096     return generateFixes();
1097   }
1098 
1099 private:
1100   bool containsOnlyComments(const AnnotatedLine &Line) {
1101     for (FormatToken *Tok = Line.First; Tok != nullptr; Tok = Tok->Next) {
1102       if (Tok->isNot(tok::comment))
1103         return false;
1104     }
1105     return true;
1106   }
1107 
1108   // Iterate through all lines and remove any empty (nested) namespaces.
1109   void checkEmptyNamespace(SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
1110     std::set<unsigned> DeletedLines;
1111     for (unsigned i = 0, e = AnnotatedLines.size(); i != e; ++i) {
1112       auto &Line = *AnnotatedLines[i];
1113       if (Line.startsWith(tok::kw_namespace) ||
1114           Line.startsWith(tok::kw_inline, tok::kw_namespace)) {
1115         checkEmptyNamespace(AnnotatedLines, i, i, DeletedLines);
1116       }
1117     }
1118 
1119     for (auto Line : DeletedLines) {
1120       FormatToken *Tok = AnnotatedLines[Line]->First;
1121       while (Tok) {
1122         deleteToken(Tok);
1123         Tok = Tok->Next;
1124       }
1125     }
1126   }
1127 
1128   // The function checks if the namespace, which starts from \p CurrentLine, and
1129   // its nested namespaces are empty and delete them if they are empty. It also
1130   // sets \p NewLine to the last line checked.
1131   // Returns true if the current namespace is empty.
1132   bool checkEmptyNamespace(SmallVectorImpl<AnnotatedLine *> &AnnotatedLines,
1133                            unsigned CurrentLine, unsigned &NewLine,
1134                            std::set<unsigned> &DeletedLines) {
1135     unsigned InitLine = CurrentLine, End = AnnotatedLines.size();
1136     if (Style.BraceWrapping.AfterNamespace) {
1137       // If the left brace is in a new line, we should consume it first so that
1138       // it does not make the namespace non-empty.
1139       // FIXME: error handling if there is no left brace.
1140       if (!AnnotatedLines[++CurrentLine]->startsWith(tok::l_brace)) {
1141         NewLine = CurrentLine;
1142         return false;
1143       }
1144     } else if (!AnnotatedLines[CurrentLine]->endsWith(tok::l_brace)) {
1145       return false;
1146     }
1147     while (++CurrentLine < End) {
1148       if (AnnotatedLines[CurrentLine]->startsWith(tok::r_brace))
1149         break;
1150 
1151       if (AnnotatedLines[CurrentLine]->startsWith(tok::kw_namespace) ||
1152           AnnotatedLines[CurrentLine]->startsWith(tok::kw_inline,
1153                                                   tok::kw_namespace)) {
1154         if (!checkEmptyNamespace(AnnotatedLines, CurrentLine, NewLine,
1155                                  DeletedLines))
1156           return false;
1157         CurrentLine = NewLine;
1158         continue;
1159       }
1160 
1161       if (containsOnlyComments(*AnnotatedLines[CurrentLine]))
1162         continue;
1163 
1164       // If there is anything other than comments or nested namespaces in the
1165       // current namespace, the namespace cannot be empty.
1166       NewLine = CurrentLine;
1167       return false;
1168     }
1169 
1170     NewLine = CurrentLine;
1171     if (CurrentLine >= End)
1172       return false;
1173 
1174     // Check if the empty namespace is actually affected by changed ranges.
1175     if (!AffectedRangeMgr.affectsCharSourceRange(CharSourceRange::getCharRange(
1176             AnnotatedLines[InitLine]->First->Tok.getLocation(),
1177             AnnotatedLines[CurrentLine]->Last->Tok.getEndLoc())))
1178       return false;
1179 
1180     for (unsigned i = InitLine; i <= CurrentLine; ++i) {
1181       DeletedLines.insert(i);
1182     }
1183 
1184     return true;
1185   }
1186 
1187   // Checks pairs {start, start->next},..., {end->previous, end} and deletes one
1188   // of the token in the pair if the left token has \p LK token kind and the
1189   // right token has \p RK token kind. If \p DeleteLeft is true, the left token
1190   // is deleted on match; otherwise, the right token is deleted.
1191   template <typename LeftKind, typename RightKind>
1192   void cleanupPair(FormatToken *Start, LeftKind LK, RightKind RK,
1193                    bool DeleteLeft) {
1194     auto NextNotDeleted = [this](const FormatToken &Tok) -> FormatToken * {
1195       for (auto *Res = Tok.Next; Res; Res = Res->Next)
1196         if (!Res->is(tok::comment) &&
1197             DeletedTokens.find(Res) == DeletedTokens.end())
1198           return Res;
1199       return nullptr;
1200     };
1201     for (auto *Left = Start; Left;) {
1202       auto *Right = NextNotDeleted(*Left);
1203       if (!Right)
1204         break;
1205       if (Left->is(LK) && Right->is(RK)) {
1206         deleteToken(DeleteLeft ? Left : Right);
1207         for (auto *Tok = Left->Next; Tok && Tok != Right; Tok = Tok->Next)
1208           deleteToken(Tok);
1209         // If the right token is deleted, we should keep the left token
1210         // unchanged and pair it with the new right token.
1211         if (!DeleteLeft)
1212           continue;
1213       }
1214       Left = Right;
1215     }
1216   }
1217 
1218   template <typename LeftKind, typename RightKind>
1219   void cleanupLeft(FormatToken *Start, LeftKind LK, RightKind RK) {
1220     cleanupPair(Start, LK, RK, /*DeleteLeft=*/true);
1221   }
1222 
1223   template <typename LeftKind, typename RightKind>
1224   void cleanupRight(FormatToken *Start, LeftKind LK, RightKind RK) {
1225     cleanupPair(Start, LK, RK, /*DeleteLeft=*/false);
1226   }
1227 
1228   // Delete the given token.
1229   inline void deleteToken(FormatToken *Tok) {
1230     if (Tok)
1231       DeletedTokens.insert(Tok);
1232   }
1233 
1234   tooling::Replacements generateFixes() {
1235     tooling::Replacements Fixes;
1236     std::vector<FormatToken *> Tokens;
1237     std::copy(DeletedTokens.begin(), DeletedTokens.end(),
1238               std::back_inserter(Tokens));
1239 
1240     // Merge multiple continuous token deletions into one big deletion so that
1241     // the number of replacements can be reduced. This makes computing affected
1242     // ranges more efficient when we run reformat on the changed code.
1243     unsigned Idx = 0;
1244     while (Idx < Tokens.size()) {
1245       unsigned St = Idx, End = Idx;
1246       while ((End + 1) < Tokens.size() &&
1247              Tokens[End]->Next == Tokens[End + 1]) {
1248         End++;
1249       }
1250       auto SR = CharSourceRange::getCharRange(Tokens[St]->Tok.getLocation(),
1251                                               Tokens[End]->Tok.getEndLoc());
1252       auto Err =
1253           Fixes.add(tooling::Replacement(Env.getSourceManager(), SR, ""));
1254       // FIXME: better error handling. for now just print error message and skip
1255       // for the release version.
1256       if (Err) {
1257         llvm::errs() << llvm::toString(std::move(Err)) << "\n";
1258         assert(false && "Fixes must not conflict!");
1259       }
1260       Idx = End + 1;
1261     }
1262 
1263     return Fixes;
1264   }
1265 
1266   // Class for less-than inequality comparason for the set `RedundantTokens`.
1267   // We store tokens in the order they appear in the translation unit so that
1268   // we do not need to sort them in `generateFixes()`.
1269   struct FormatTokenLess {
1270     FormatTokenLess(const SourceManager &SM) : SM(SM) {}
1271 
1272     bool operator()(const FormatToken *LHS, const FormatToken *RHS) const {
1273       return SM.isBeforeInTranslationUnit(LHS->Tok.getLocation(),
1274                                           RHS->Tok.getLocation());
1275     }
1276     const SourceManager &SM;
1277   };
1278 
1279   // Tokens to be deleted.
1280   std::set<FormatToken *, FormatTokenLess> DeletedTokens;
1281 };
1282 
1283 struct IncludeDirective {
1284   StringRef Filename;
1285   StringRef Text;
1286   unsigned Offset;
1287   int Category;
1288 };
1289 
1290 } // end anonymous namespace
1291 
1292 // Determines whether 'Ranges' intersects with ('Start', 'End').
1293 static bool affectsRange(ArrayRef<tooling::Range> Ranges, unsigned Start,
1294                          unsigned End) {
1295   for (auto Range : Ranges) {
1296     if (Range.getOffset() < End &&
1297         Range.getOffset() + Range.getLength() > Start)
1298       return true;
1299   }
1300   return false;
1301 }
1302 
1303 // Returns a pair (Index, OffsetToEOL) describing the position of the cursor
1304 // before sorting/deduplicating. Index is the index of the include under the
1305 // cursor in the original set of includes. If this include has duplicates, it is
1306 // the index of the first of the duplicates as the others are going to be
1307 // removed. OffsetToEOL describes the cursor's position relative to the end of
1308 // its current line.
1309 // If `Cursor` is not on any #include, `Index` will be UINT_MAX.
1310 static std::pair<unsigned, unsigned>
1311 FindCursorIndex(const SmallVectorImpl<IncludeDirective> &Includes,
1312                 const SmallVectorImpl<unsigned> &Indices, unsigned Cursor) {
1313   unsigned CursorIndex = UINT_MAX;
1314   unsigned OffsetToEOL = 0;
1315   for (int i = 0, e = Includes.size(); i != e; ++i) {
1316     unsigned Start = Includes[Indices[i]].Offset;
1317     unsigned End = Start + Includes[Indices[i]].Text.size();
1318     if (!(Cursor >= Start && Cursor < End))
1319       continue;
1320     CursorIndex = Indices[i];
1321     OffsetToEOL = End - Cursor;
1322     // Put the cursor on the only remaining #include among the duplicate
1323     // #includes.
1324     while (--i >= 0 && Includes[CursorIndex].Text == Includes[Indices[i]].Text)
1325       CursorIndex = i;
1326     break;
1327   }
1328   return std::make_pair(CursorIndex, OffsetToEOL);
1329 }
1330 
1331 // Sorts and deduplicate a block of includes given by 'Includes' alphabetically
1332 // adding the necessary replacement to 'Replaces'. 'Includes' must be in strict
1333 // source order.
1334 // #include directives with the same text will be deduplicated, and only the
1335 // first #include in the duplicate #includes remains. If the `Cursor` is
1336 // provided and put on a deleted #include, it will be moved to the remaining
1337 // #include in the duplicate #includes.
1338 static void sortCppIncludes(const FormatStyle &Style,
1339                             const SmallVectorImpl<IncludeDirective> &Includes,
1340                             ArrayRef<tooling::Range> Ranges, StringRef FileName,
1341                             tooling::Replacements &Replaces, unsigned *Cursor) {
1342   unsigned IncludesBeginOffset = Includes.front().Offset;
1343   unsigned IncludesEndOffset =
1344       Includes.back().Offset + Includes.back().Text.size();
1345   unsigned IncludesBlockSize = IncludesEndOffset - IncludesBeginOffset;
1346   if (!affectsRange(Ranges, IncludesBeginOffset, IncludesEndOffset))
1347     return;
1348   SmallVector<unsigned, 16> Indices;
1349   for (unsigned i = 0, e = Includes.size(); i != e; ++i)
1350     Indices.push_back(i);
1351   std::stable_sort(
1352       Indices.begin(), Indices.end(), [&](unsigned LHSI, unsigned RHSI) {
1353         return std::tie(Includes[LHSI].Category, Includes[LHSI].Filename) <
1354                std::tie(Includes[RHSI].Category, Includes[RHSI].Filename);
1355       });
1356   // The index of the include on which the cursor will be put after
1357   // sorting/deduplicating.
1358   unsigned CursorIndex;
1359   // The offset from cursor to the end of line.
1360   unsigned CursorToEOLOffset;
1361   if (Cursor)
1362     std::tie(CursorIndex, CursorToEOLOffset) =
1363         FindCursorIndex(Includes, Indices, *Cursor);
1364 
1365   // Deduplicate #includes.
1366   Indices.erase(std::unique(Indices.begin(), Indices.end(),
1367                             [&](unsigned LHSI, unsigned RHSI) {
1368                               return Includes[LHSI].Text == Includes[RHSI].Text;
1369                             }),
1370                 Indices.end());
1371 
1372   // If the #includes are out of order, we generate a single replacement fixing
1373   // the entire block. Otherwise, no replacement is generated.
1374   if (Indices.size() == Includes.size() &&
1375       std::is_sorted(Indices.begin(), Indices.end()))
1376     return;
1377 
1378   std::string result;
1379   for (unsigned Index : Indices) {
1380     if (!result.empty())
1381       result += "\n";
1382     result += Includes[Index].Text;
1383     if (Cursor && CursorIndex == Index)
1384       *Cursor = IncludesBeginOffset + result.size() - CursorToEOLOffset;
1385   }
1386 
1387   auto Err = Replaces.add(tooling::Replacement(
1388       FileName, Includes.front().Offset, IncludesBlockSize, result));
1389   // FIXME: better error handling. For now, just skip the replacement for the
1390   // release version.
1391   if (Err) {
1392     llvm::errs() << llvm::toString(std::move(Err)) << "\n";
1393     assert(false);
1394   }
1395 }
1396 
1397 namespace {
1398 
1399 // This class manages priorities of #include categories and calculates
1400 // priorities for headers.
1401 class IncludeCategoryManager {
1402 public:
1403   IncludeCategoryManager(const FormatStyle &Style, StringRef FileName)
1404       : Style(Style), FileName(FileName) {
1405     FileStem = llvm::sys::path::stem(FileName);
1406     for (const auto &Category : Style.IncludeCategories)
1407       CategoryRegexs.emplace_back(Category.Regex);
1408     IsMainFile = FileName.endswith(".c") || FileName.endswith(".cc") ||
1409                  FileName.endswith(".cpp") || FileName.endswith(".c++") ||
1410                  FileName.endswith(".cxx") || FileName.endswith(".m") ||
1411                  FileName.endswith(".mm");
1412   }
1413 
1414   // Returns the priority of the category which \p IncludeName belongs to.
1415   // If \p CheckMainHeader is true and \p IncludeName is a main header, returns
1416   // 0. Otherwise, returns the priority of the matching category or INT_MAX.
1417   int getIncludePriority(StringRef IncludeName, bool CheckMainHeader) {
1418     int Ret = INT_MAX;
1419     for (unsigned i = 0, e = CategoryRegexs.size(); i != e; ++i)
1420       if (CategoryRegexs[i].match(IncludeName)) {
1421         Ret = Style.IncludeCategories[i].Priority;
1422         break;
1423       }
1424     if (CheckMainHeader && IsMainFile && Ret > 0 && isMainHeader(IncludeName))
1425       Ret = 0;
1426     return Ret;
1427   }
1428 
1429 private:
1430   bool isMainHeader(StringRef IncludeName) const {
1431     if (!IncludeName.startswith("\""))
1432       return false;
1433     StringRef HeaderStem =
1434         llvm::sys::path::stem(IncludeName.drop_front(1).drop_back(1));
1435     if (FileStem.startswith(HeaderStem)) {
1436       llvm::Regex MainIncludeRegex(
1437           (HeaderStem + Style.IncludeIsMainRegex).str());
1438       if (MainIncludeRegex.match(FileStem))
1439         return true;
1440     }
1441     return false;
1442   }
1443 
1444   const FormatStyle &Style;
1445   bool IsMainFile;
1446   StringRef FileName;
1447   StringRef FileStem;
1448   SmallVector<llvm::Regex, 4> CategoryRegexs;
1449 };
1450 
1451 const char IncludeRegexPattern[] =
1452     R"(^[\t\ ]*#[\t\ ]*(import|include)[^"<]*(["<][^">]*[">]))";
1453 
1454 } // anonymous namespace
1455 
1456 tooling::Replacements sortCppIncludes(const FormatStyle &Style, StringRef Code,
1457                                       ArrayRef<tooling::Range> Ranges,
1458                                       StringRef FileName,
1459                                       tooling::Replacements &Replaces,
1460                                       unsigned *Cursor) {
1461   unsigned Prev = 0;
1462   unsigned SearchFrom = 0;
1463   llvm::Regex IncludeRegex(IncludeRegexPattern);
1464   SmallVector<StringRef, 4> Matches;
1465   SmallVector<IncludeDirective, 16> IncludesInBlock;
1466 
1467   // In compiled files, consider the first #include to be the main #include of
1468   // the file if it is not a system #include. This ensures that the header
1469   // doesn't have hidden dependencies
1470   // (http://llvm.org/docs/CodingStandards.html#include-style).
1471   //
1472   // FIXME: Do some sanity checking, e.g. edit distance of the base name, to fix
1473   // cases where the first #include is unlikely to be the main header.
1474   IncludeCategoryManager Categories(Style, FileName);
1475   bool FirstIncludeBlock = true;
1476   bool MainIncludeFound = false;
1477   bool FormattingOff = false;
1478 
1479   for (;;) {
1480     auto Pos = Code.find('\n', SearchFrom);
1481     StringRef Line =
1482         Code.substr(Prev, (Pos != StringRef::npos ? Pos : Code.size()) - Prev);
1483 
1484     StringRef Trimmed = Line.trim();
1485     if (Trimmed == "// clang-format off")
1486       FormattingOff = true;
1487     else if (Trimmed == "// clang-format on")
1488       FormattingOff = false;
1489 
1490     if (!FormattingOff && !Line.endswith("\\")) {
1491       if (IncludeRegex.match(Line, &Matches)) {
1492         StringRef IncludeName = Matches[2];
1493         int Category = Categories.getIncludePriority(
1494             IncludeName,
1495             /*CheckMainHeader=*/!MainIncludeFound && FirstIncludeBlock);
1496         if (Category == 0)
1497           MainIncludeFound = true;
1498         IncludesInBlock.push_back({IncludeName, Line, Prev, Category});
1499       } else if (!IncludesInBlock.empty()) {
1500         sortCppIncludes(Style, IncludesInBlock, Ranges, FileName, Replaces,
1501                         Cursor);
1502         IncludesInBlock.clear();
1503         FirstIncludeBlock = false;
1504       }
1505       Prev = Pos + 1;
1506     }
1507     if (Pos == StringRef::npos || Pos + 1 == Code.size())
1508       break;
1509     SearchFrom = Pos + 1;
1510   }
1511   if (!IncludesInBlock.empty())
1512     sortCppIncludes(Style, IncludesInBlock, Ranges, FileName, Replaces, Cursor);
1513   return Replaces;
1514 }
1515 
1516 bool isMpegTS(StringRef Code) {
1517   // MPEG transport streams use the ".ts" file extension. clang-format should
1518   // not attempt to format those. MPEG TS' frame format starts with 0x47 every
1519   // 189 bytes - detect that and return.
1520   return Code.size() > 188 && Code[0] == 0x47 && Code[188] == 0x47;
1521 }
1522 
1523 tooling::Replacements sortIncludes(const FormatStyle &Style, StringRef Code,
1524                                    ArrayRef<tooling::Range> Ranges,
1525                                    StringRef FileName, unsigned *Cursor) {
1526   tooling::Replacements Replaces;
1527   if (!Style.SortIncludes)
1528     return Replaces;
1529   if (Style.Language == FormatStyle::LanguageKind::LK_JavaScript &&
1530       isMpegTS(Code))
1531     return Replaces;
1532   if (Style.Language == FormatStyle::LanguageKind::LK_JavaScript)
1533     return sortJavaScriptImports(Style, Code, Ranges, FileName);
1534   sortCppIncludes(Style, Code, Ranges, FileName, Replaces, Cursor);
1535   return Replaces;
1536 }
1537 
1538 template <typename T>
1539 static llvm::Expected<tooling::Replacements>
1540 processReplacements(T ProcessFunc, StringRef Code,
1541                     const tooling::Replacements &Replaces,
1542                     const FormatStyle &Style) {
1543   if (Replaces.empty())
1544     return tooling::Replacements();
1545 
1546   auto NewCode = applyAllReplacements(Code, Replaces);
1547   if (!NewCode)
1548     return NewCode.takeError();
1549   std::vector<tooling::Range> ChangedRanges = Replaces.getAffectedRanges();
1550   StringRef FileName = Replaces.begin()->getFilePath();
1551 
1552   tooling::Replacements FormatReplaces =
1553       ProcessFunc(Style, *NewCode, ChangedRanges, FileName);
1554 
1555   return Replaces.merge(FormatReplaces);
1556 }
1557 
1558 llvm::Expected<tooling::Replacements>
1559 formatReplacements(StringRef Code, const tooling::Replacements &Replaces,
1560                    const FormatStyle &Style) {
1561   // We need to use lambda function here since there are two versions of
1562   // `sortIncludes`.
1563   auto SortIncludes = [](const FormatStyle &Style, StringRef Code,
1564                          std::vector<tooling::Range> Ranges,
1565                          StringRef FileName) -> tooling::Replacements {
1566     return sortIncludes(Style, Code, Ranges, FileName);
1567   };
1568   auto SortedReplaces =
1569       processReplacements(SortIncludes, Code, Replaces, Style);
1570   if (!SortedReplaces)
1571     return SortedReplaces.takeError();
1572 
1573   // We need to use lambda function here since there are two versions of
1574   // `reformat`.
1575   auto Reformat = [](const FormatStyle &Style, StringRef Code,
1576                      std::vector<tooling::Range> Ranges,
1577                      StringRef FileName) -> tooling::Replacements {
1578     return reformat(Style, Code, Ranges, FileName);
1579   };
1580   return processReplacements(Reformat, Code, *SortedReplaces, Style);
1581 }
1582 
1583 namespace {
1584 
1585 inline bool isHeaderInsertion(const tooling::Replacement &Replace) {
1586   return Replace.getOffset() == UINT_MAX && Replace.getLength() == 0 &&
1587          llvm::Regex(IncludeRegexPattern).match(Replace.getReplacementText());
1588 }
1589 
1590 inline bool isHeaderDeletion(const tooling::Replacement &Replace) {
1591   return Replace.getOffset() == UINT_MAX && Replace.getLength() == 1;
1592 }
1593 
1594 // Returns the offset after skipping a sequence of tokens, matched by \p
1595 // GetOffsetAfterSequence, from the start of the code.
1596 // \p GetOffsetAfterSequence should be a function that matches a sequence of
1597 // tokens and returns an offset after the sequence.
1598 unsigned getOffsetAfterTokenSequence(
1599     StringRef FileName, StringRef Code, const FormatStyle &Style,
1600     llvm::function_ref<unsigned(const SourceManager &, Lexer &, Token &)>
1601         GetOffsetAfterSequence) {
1602   std::unique_ptr<Environment> Env =
1603       Environment::CreateVirtualEnvironment(Code, FileName, /*Ranges=*/{});
1604   const SourceManager &SourceMgr = Env->getSourceManager();
1605   Lexer Lex(Env->getFileID(), SourceMgr.getBuffer(Env->getFileID()), SourceMgr,
1606             getFormattingLangOpts(Style));
1607   Token Tok;
1608   // Get the first token.
1609   Lex.LexFromRawLexer(Tok);
1610   return GetOffsetAfterSequence(SourceMgr, Lex, Tok);
1611 }
1612 
1613 // Check if a sequence of tokens is like "#<Name> <raw_identifier>". If it is,
1614 // \p Tok will be the token after this directive; otherwise, it can be any token
1615 // after the given \p Tok (including \p Tok).
1616 bool checkAndConsumeDirectiveWithName(Lexer &Lex, StringRef Name, Token &Tok) {
1617   bool Matched = Tok.is(tok::hash) && !Lex.LexFromRawLexer(Tok) &&
1618                  Tok.is(tok::raw_identifier) &&
1619                  Tok.getRawIdentifier() == Name && !Lex.LexFromRawLexer(Tok) &&
1620                  Tok.is(tok::raw_identifier);
1621   if (Matched)
1622     Lex.LexFromRawLexer(Tok);
1623   return Matched;
1624 }
1625 
1626 void skipComments(Lexer &Lex, Token &Tok) {
1627   while (Tok.is(tok::comment))
1628     if (Lex.LexFromRawLexer(Tok))
1629       return;
1630 }
1631 
1632 // Returns the offset after header guard directives and any comments
1633 // before/after header guards. If no header guard presents in the code, this
1634 // will returns the offset after skipping all comments from the start of the
1635 // code.
1636 unsigned getOffsetAfterHeaderGuardsAndComments(StringRef FileName,
1637                                                StringRef Code,
1638                                                const FormatStyle &Style) {
1639   return getOffsetAfterTokenSequence(
1640       FileName, Code, Style,
1641       [](const SourceManager &SM, Lexer &Lex, Token Tok) {
1642         skipComments(Lex, Tok);
1643         unsigned InitialOffset = SM.getFileOffset(Tok.getLocation());
1644         if (checkAndConsumeDirectiveWithName(Lex, "ifndef", Tok)) {
1645           skipComments(Lex, Tok);
1646           if (checkAndConsumeDirectiveWithName(Lex, "define", Tok))
1647             return SM.getFileOffset(Tok.getLocation());
1648         }
1649         return InitialOffset;
1650       });
1651 }
1652 
1653 // Check if a sequence of tokens is like
1654 //    "#include ("header.h" | <header.h>)".
1655 // If it is, \p Tok will be the token after this directive; otherwise, it can be
1656 // any token after the given \p Tok (including \p Tok).
1657 bool checkAndConsumeInclusiveDirective(Lexer &Lex, Token &Tok) {
1658   auto Matched = [&]() {
1659     Lex.LexFromRawLexer(Tok);
1660     return true;
1661   };
1662   if (Tok.is(tok::hash) && !Lex.LexFromRawLexer(Tok) &&
1663       Tok.is(tok::raw_identifier) && Tok.getRawIdentifier() == "include") {
1664     if (Lex.LexFromRawLexer(Tok))
1665       return false;
1666     if (Tok.is(tok::string_literal))
1667       return Matched();
1668     if (Tok.is(tok::less)) {
1669       while (!Lex.LexFromRawLexer(Tok) && Tok.isNot(tok::greater)) {
1670       }
1671       if (Tok.is(tok::greater))
1672         return Matched();
1673     }
1674   }
1675   return false;
1676 }
1677 
1678 // Returns the offset of the last #include directive after which a new
1679 // #include can be inserted. This ignores #include's after the #include block(s)
1680 // in the beginning of a file to avoid inserting headers into code sections
1681 // where new #include's should not be added by default.
1682 // These code sections include:
1683 //      - raw string literals (containing #include).
1684 //      - #if blocks.
1685 //      - Special #include's among declarations (e.g. functions).
1686 //
1687 // If no #include after which a new #include can be inserted, this returns the
1688 // offset after skipping all comments from the start of the code.
1689 // Inserting after an #include is not allowed if it comes after code that is not
1690 // #include (e.g. pre-processing directive that is not #include, declarations).
1691 unsigned getMaxHeaderInsertionOffset(StringRef FileName, StringRef Code,
1692                                      const FormatStyle &Style) {
1693   return getOffsetAfterTokenSequence(
1694       FileName, Code, Style,
1695       [](const SourceManager &SM, Lexer &Lex, Token Tok) {
1696         skipComments(Lex, Tok);
1697         unsigned MaxOffset = SM.getFileOffset(Tok.getLocation());
1698         while (checkAndConsumeInclusiveDirective(Lex, Tok))
1699           MaxOffset = SM.getFileOffset(Tok.getLocation());
1700         return MaxOffset;
1701       });
1702 }
1703 
1704 bool isDeletedHeader(llvm::StringRef HeaderName,
1705                      const std::set<llvm::StringRef> &HeadersToDelete) {
1706   return HeadersToDelete.count(HeaderName) ||
1707          HeadersToDelete.count(HeaderName.trim("\"<>"));
1708 }
1709 
1710 // FIXME: insert empty lines between newly created blocks.
1711 tooling::Replacements
1712 fixCppIncludeInsertions(StringRef Code, const tooling::Replacements &Replaces,
1713                         const FormatStyle &Style) {
1714   if (!Style.isCpp())
1715     return Replaces;
1716 
1717   tooling::Replacements HeaderInsertions;
1718   std::set<llvm::StringRef> HeadersToDelete;
1719   tooling::Replacements Result;
1720   for (const auto &R : Replaces) {
1721     if (isHeaderInsertion(R)) {
1722       // Replacements from \p Replaces must be conflict-free already, so we can
1723       // simply consume the error.
1724       llvm::consumeError(HeaderInsertions.add(R));
1725     } else if (isHeaderDeletion(R)) {
1726       HeadersToDelete.insert(R.getReplacementText());
1727     } else if (R.getOffset() == UINT_MAX) {
1728       llvm::errs() << "Insertions other than header #include insertion are "
1729                       "not supported! "
1730                    << R.getReplacementText() << "\n";
1731     } else {
1732       llvm::consumeError(Result.add(R));
1733     }
1734   }
1735   if (HeaderInsertions.empty() && HeadersToDelete.empty())
1736     return Replaces;
1737 
1738   llvm::Regex IncludeRegex(IncludeRegexPattern);
1739   llvm::Regex DefineRegex(R"(^[\t\ ]*#[\t\ ]*define[\t\ ]*[^\\]*$)");
1740   SmallVector<StringRef, 4> Matches;
1741 
1742   StringRef FileName = Replaces.begin()->getFilePath();
1743   IncludeCategoryManager Categories(Style, FileName);
1744 
1745   // Record the offset of the end of the last include in each category.
1746   std::map<int, int> CategoryEndOffsets;
1747   // All possible priorities.
1748   // Add 0 for main header and INT_MAX for headers that are not in any category.
1749   std::set<int> Priorities = {0, INT_MAX};
1750   for (const auto &Category : Style.IncludeCategories)
1751     Priorities.insert(Category.Priority);
1752   int FirstIncludeOffset = -1;
1753   // All new headers should be inserted after this offset.
1754   unsigned MinInsertOffset =
1755       getOffsetAfterHeaderGuardsAndComments(FileName, Code, Style);
1756   StringRef TrimmedCode = Code.drop_front(MinInsertOffset);
1757   // Max insertion offset in the original code.
1758   unsigned MaxInsertOffset =
1759       MinInsertOffset +
1760       getMaxHeaderInsertionOffset(FileName, TrimmedCode, Style);
1761   SmallVector<StringRef, 32> Lines;
1762   TrimmedCode.split(Lines, '\n');
1763   unsigned Offset = MinInsertOffset;
1764   unsigned NextLineOffset;
1765   std::set<StringRef> ExistingIncludes;
1766   for (auto Line : Lines) {
1767     NextLineOffset = std::min(Code.size(), Offset + Line.size() + 1);
1768     if (IncludeRegex.match(Line, &Matches)) {
1769       // The header name with quotes or angle brackets.
1770       StringRef IncludeName = Matches[2];
1771       ExistingIncludes.insert(IncludeName);
1772       // Only record the offset of current #include if we can insert after it.
1773       if (Offset <= MaxInsertOffset) {
1774         int Category = Categories.getIncludePriority(
1775             IncludeName, /*CheckMainHeader=*/FirstIncludeOffset < 0);
1776         CategoryEndOffsets[Category] = NextLineOffset;
1777         if (FirstIncludeOffset < 0)
1778           FirstIncludeOffset = Offset;
1779       }
1780       if (isDeletedHeader(IncludeName, HeadersToDelete)) {
1781         // If this is the last line without trailing newline, we need to make
1782         // sure we don't delete across the file boundary.
1783         unsigned Length = std::min(Line.size() + 1, Code.size() - Offset);
1784         llvm::Error Err =
1785             Result.add(tooling::Replacement(FileName, Offset, Length, ""));
1786         if (Err) {
1787           // Ignore the deletion on conflict.
1788           llvm::errs() << "Failed to add header deletion replacement for "
1789                        << IncludeName << ": " << llvm::toString(std::move(Err))
1790                        << "\n";
1791         }
1792       }
1793     }
1794     Offset = NextLineOffset;
1795   }
1796 
1797   // Populate CategoryEndOfssets:
1798   // - Ensure that CategoryEndOffset[Highest] is always populated.
1799   // - If CategoryEndOffset[Priority] isn't set, use the next higher value that
1800   //   is set, up to CategoryEndOffset[Highest].
1801   auto Highest = Priorities.begin();
1802   if (CategoryEndOffsets.find(*Highest) == CategoryEndOffsets.end()) {
1803     if (FirstIncludeOffset >= 0)
1804       CategoryEndOffsets[*Highest] = FirstIncludeOffset;
1805     else
1806       CategoryEndOffsets[*Highest] = MinInsertOffset;
1807   }
1808   // By this point, CategoryEndOffset[Highest] is always set appropriately:
1809   //  - to an appropriate location before/after existing #includes, or
1810   //  - to right after the header guard, or
1811   //  - to the beginning of the file.
1812   for (auto I = ++Priorities.begin(), E = Priorities.end(); I != E; ++I)
1813     if (CategoryEndOffsets.find(*I) == CategoryEndOffsets.end())
1814       CategoryEndOffsets[*I] = CategoryEndOffsets[*std::prev(I)];
1815 
1816   bool NeedNewLineAtEnd = !Code.empty() && Code.back() != '\n';
1817   for (const auto &R : HeaderInsertions) {
1818     auto IncludeDirective = R.getReplacementText();
1819     bool Matched = IncludeRegex.match(IncludeDirective, &Matches);
1820     assert(Matched && "Header insertion replacement must have replacement text "
1821                       "'#include ...'");
1822     (void)Matched;
1823     auto IncludeName = Matches[2];
1824     if (ExistingIncludes.find(IncludeName) != ExistingIncludes.end()) {
1825       DEBUG(llvm::dbgs() << "Skip adding existing include : " << IncludeName
1826                          << "\n");
1827       continue;
1828     }
1829     int Category =
1830         Categories.getIncludePriority(IncludeName, /*CheckMainHeader=*/true);
1831     Offset = CategoryEndOffsets[Category];
1832     std::string NewInclude = !IncludeDirective.endswith("\n")
1833                                  ? (IncludeDirective + "\n").str()
1834                                  : IncludeDirective.str();
1835     // When inserting headers at end of the code, also append '\n' to the code
1836     // if it does not end with '\n'.
1837     if (NeedNewLineAtEnd && Offset == Code.size()) {
1838       NewInclude = "\n" + NewInclude;
1839       NeedNewLineAtEnd = false;
1840     }
1841     auto NewReplace = tooling::Replacement(FileName, Offset, 0, NewInclude);
1842     auto Err = Result.add(NewReplace);
1843     if (Err) {
1844       llvm::consumeError(std::move(Err));
1845       unsigned NewOffset = Result.getShiftedCodePosition(Offset);
1846       NewReplace = tooling::Replacement(FileName, NewOffset, 0, NewInclude);
1847       Result = Result.merge(tooling::Replacements(NewReplace));
1848     }
1849   }
1850   return Result;
1851 }
1852 
1853 } // anonymous namespace
1854 
1855 llvm::Expected<tooling::Replacements>
1856 cleanupAroundReplacements(StringRef Code, const tooling::Replacements &Replaces,
1857                           const FormatStyle &Style) {
1858   // We need to use lambda function here since there are two versions of
1859   // `cleanup`.
1860   auto Cleanup = [](const FormatStyle &Style, StringRef Code,
1861                     std::vector<tooling::Range> Ranges,
1862                     StringRef FileName) -> tooling::Replacements {
1863     return cleanup(Style, Code, Ranges, FileName);
1864   };
1865   // Make header insertion replacements insert new headers into correct blocks.
1866   tooling::Replacements NewReplaces =
1867       fixCppIncludeInsertions(Code, Replaces, Style);
1868   return processReplacements(Cleanup, Code, NewReplaces, Style);
1869 }
1870 
1871 tooling::Replacements reformat(const FormatStyle &Style, StringRef Code,
1872                                ArrayRef<tooling::Range> Ranges,
1873                                StringRef FileName,
1874                                FormattingAttemptStatus *Status) {
1875   FormatStyle Expanded = expandPresets(Style);
1876   if (Expanded.DisableFormat)
1877     return tooling::Replacements();
1878   if (Expanded.Language == FormatStyle::LK_JavaScript && isMpegTS(Code))
1879     return tooling::Replacements();
1880   auto Env = Environment::CreateVirtualEnvironment(Code, FileName, Ranges);
1881 
1882   auto reformatAfterApplying = [&] (TokenAnalyzer& Fixer) {
1883     tooling::Replacements Fixes = Fixer.process();
1884     if (!Fixes.empty()) {
1885       auto NewCode = applyAllReplacements(Code, Fixes);
1886       if (NewCode) {
1887         auto NewEnv = Environment::CreateVirtualEnvironment(
1888             *NewCode, FileName,
1889             tooling::calculateRangesAfterReplacements(Fixes, Ranges));
1890         Formatter Format(*NewEnv, Expanded, Status);
1891         return Fixes.merge(Format.process());
1892       }
1893     }
1894     Formatter Format(*Env, Expanded, Status);
1895     return Format.process();
1896   };
1897 
1898   if (Style.Language == FormatStyle::LK_Cpp &&
1899       Style.FixNamespaceComments) {
1900     NamespaceEndCommentsFixer CommentsFixer(*Env, Expanded);
1901     return reformatAfterApplying(CommentsFixer);
1902   }
1903 
1904   if (Style.Language == FormatStyle::LK_JavaScript &&
1905       Style.JavaScriptQuotes != FormatStyle::JSQS_Leave) {
1906     JavaScriptRequoter Requoter(*Env, Expanded);
1907     return reformatAfterApplying(Requoter);
1908   }
1909 
1910   Formatter Format(*Env, Expanded, Status);
1911   return Format.process();
1912 }
1913 
1914 tooling::Replacements cleanup(const FormatStyle &Style, StringRef Code,
1915                               ArrayRef<tooling::Range> Ranges,
1916                               StringRef FileName) {
1917   // cleanups only apply to C++ (they mostly concern ctor commas etc.)
1918   if (Style.Language != FormatStyle::LK_Cpp)
1919     return tooling::Replacements();
1920   std::unique_ptr<Environment> Env =
1921       Environment::CreateVirtualEnvironment(Code, FileName, Ranges);
1922   Cleaner Clean(*Env, Style);
1923   return Clean.process();
1924 }
1925 
1926 tooling::Replacements reformat(const FormatStyle &Style, StringRef Code,
1927                                ArrayRef<tooling::Range> Ranges,
1928                                StringRef FileName, bool *IncompleteFormat) {
1929   FormattingAttemptStatus Status;
1930   auto Result = reformat(Style, Code, Ranges, FileName, &Status);
1931   if (!Status.FormatComplete)
1932     *IncompleteFormat = true;
1933   return Result;
1934 }
1935 
1936 tooling::Replacements fixNamespaceEndComments(const FormatStyle &Style,
1937                                               StringRef Code,
1938                                               ArrayRef<tooling::Range> Ranges,
1939                                               StringRef FileName) {
1940   std::unique_ptr<Environment> Env =
1941       Environment::CreateVirtualEnvironment(Code, FileName, Ranges);
1942   NamespaceEndCommentsFixer Fix(*Env, Style);
1943   return Fix.process();
1944 }
1945 
1946 LangOptions getFormattingLangOpts(const FormatStyle &Style) {
1947   LangOptions LangOpts;
1948   LangOpts.CPlusPlus = 1;
1949   LangOpts.CPlusPlus11 = Style.Standard == FormatStyle::LS_Cpp03 ? 0 : 1;
1950   LangOpts.CPlusPlus14 = Style.Standard == FormatStyle::LS_Cpp03 ? 0 : 1;
1951   LangOpts.CPlusPlus1z = Style.Standard == FormatStyle::LS_Cpp03 ? 0 : 1;
1952   LangOpts.LineComment = 1;
1953   bool AlternativeOperators = Style.isCpp();
1954   LangOpts.CXXOperatorNames = AlternativeOperators ? 1 : 0;
1955   LangOpts.Bool = 1;
1956   LangOpts.ObjC1 = 1;
1957   LangOpts.ObjC2 = 1;
1958   LangOpts.MicrosoftExt = 1;    // To get kw___try, kw___finally.
1959   LangOpts.DeclSpecKeyword = 1; // To get __declspec.
1960   return LangOpts;
1961 }
1962 
1963 const char *StyleOptionHelpDescription =
1964     "Coding style, currently supports:\n"
1965     "  LLVM, Google, Chromium, Mozilla, WebKit.\n"
1966     "Use -style=file to load style configuration from\n"
1967     ".clang-format file located in one of the parent\n"
1968     "directories of the source file (or current\n"
1969     "directory for stdin).\n"
1970     "Use -style=\"{key: value, ...}\" to set specific\n"
1971     "parameters, e.g.:\n"
1972     "  -style=\"{BasedOnStyle: llvm, IndentWidth: 8}\"";
1973 
1974 static FormatStyle::LanguageKind getLanguageByFileName(StringRef FileName) {
1975   if (FileName.endswith(".java"))
1976     return FormatStyle::LK_Java;
1977   if (FileName.endswith_lower(".js") || FileName.endswith_lower(".ts"))
1978     return FormatStyle::LK_JavaScript; // JavaScript or TypeScript.
1979   if (FileName.endswith(".m") || FileName.endswith(".mm"))
1980     return FormatStyle::LK_ObjC;
1981   if (FileName.endswith_lower(".proto") ||
1982       FileName.endswith_lower(".protodevel"))
1983     return FormatStyle::LK_Proto;
1984   if (FileName.endswith_lower(".td"))
1985     return FormatStyle::LK_TableGen;
1986   return FormatStyle::LK_Cpp;
1987 }
1988 
1989 llvm::Expected<FormatStyle> getStyle(StringRef StyleName, StringRef FileName,
1990                                      StringRef FallbackStyleName,
1991                                      StringRef Code, vfs::FileSystem *FS) {
1992   if (!FS) {
1993     FS = vfs::getRealFileSystem().get();
1994   }
1995   FormatStyle Style = getLLVMStyle();
1996   Style.Language = getLanguageByFileName(FileName);
1997 
1998   // This is a very crude detection of whether a header contains ObjC code that
1999   // should be improved over time and probably be done on tokens, not one the
2000   // bare content of the file.
2001   if (Style.Language == FormatStyle::LK_Cpp && FileName.endswith(".h") &&
2002       (Code.contains("\n- (") || Code.contains("\n+ (")))
2003     Style.Language = FormatStyle::LK_ObjC;
2004 
2005   FormatStyle FallbackStyle = getNoStyle();
2006   if (!getPredefinedStyle(FallbackStyleName, Style.Language, &FallbackStyle))
2007     return make_string_error("Invalid fallback style \"" + FallbackStyleName);
2008 
2009   if (StyleName.startswith("{")) {
2010     // Parse YAML/JSON style from the command line.
2011     if (std::error_code ec = parseConfiguration(StyleName, &Style))
2012       return make_string_error("Error parsing -style: " + ec.message());
2013     return Style;
2014   }
2015 
2016   if (!StyleName.equals_lower("file")) {
2017     if (!getPredefinedStyle(StyleName, Style.Language, &Style))
2018       return make_string_error("Invalid value for -style");
2019     return Style;
2020   }
2021 
2022   // Look for .clang-format/_clang-format file in the file's parent directories.
2023   SmallString<128> UnsuitableConfigFiles;
2024   SmallString<128> Path(FileName);
2025   if (std::error_code EC = FS->makeAbsolute(Path))
2026     return make_string_error(EC.message());
2027 
2028   for (StringRef Directory = Path; !Directory.empty();
2029        Directory = llvm::sys::path::parent_path(Directory)) {
2030 
2031     auto Status = FS->status(Directory);
2032     if (!Status ||
2033         Status->getType() != llvm::sys::fs::file_type::directory_file) {
2034       continue;
2035     }
2036 
2037     SmallString<128> ConfigFile(Directory);
2038 
2039     llvm::sys::path::append(ConfigFile, ".clang-format");
2040     DEBUG(llvm::dbgs() << "Trying " << ConfigFile << "...\n");
2041 
2042     Status = FS->status(ConfigFile.str());
2043     bool FoundConfigFile =
2044         Status && (Status->getType() == llvm::sys::fs::file_type::regular_file);
2045     if (!FoundConfigFile) {
2046       // Try _clang-format too, since dotfiles are not commonly used on Windows.
2047       ConfigFile = Directory;
2048       llvm::sys::path::append(ConfigFile, "_clang-format");
2049       DEBUG(llvm::dbgs() << "Trying " << ConfigFile << "...\n");
2050       Status = FS->status(ConfigFile.str());
2051       FoundConfigFile = Status && (Status->getType() ==
2052                                    llvm::sys::fs::file_type::regular_file);
2053     }
2054 
2055     if (FoundConfigFile) {
2056       llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Text =
2057           FS->getBufferForFile(ConfigFile.str());
2058       if (std::error_code EC = Text.getError())
2059         return make_string_error(EC.message());
2060       if (std::error_code ec =
2061               parseConfiguration(Text.get()->getBuffer(), &Style)) {
2062         if (ec == ParseError::Unsuitable) {
2063           if (!UnsuitableConfigFiles.empty())
2064             UnsuitableConfigFiles.append(", ");
2065           UnsuitableConfigFiles.append(ConfigFile);
2066           continue;
2067         }
2068         return make_string_error("Error reading " + ConfigFile + ": " +
2069                                  ec.message());
2070       }
2071       DEBUG(llvm::dbgs() << "Using configuration file " << ConfigFile << "\n");
2072       return Style;
2073     }
2074   }
2075   if (!UnsuitableConfigFiles.empty())
2076     return make_string_error("Configuration file(s) do(es) not support " +
2077                              getLanguageName(Style.Language) + ": " +
2078                              UnsuitableConfigFiles);
2079   return FallbackStyle;
2080 }
2081 
2082 } // namespace format
2083 } // namespace clang
2084