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