1 //===--- Format.h - Format C++ code -----------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// Various functions to configurably format source code.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CLANG_FORMAT_FORMAT_H
16 #define LLVM_CLANG_FORMAT_FORMAT_H
18 #include "clang/Basic/LangOptions.h"
19 #include "clang/Tooling/Core/Replacement.h"
20 #include "llvm/ADT/ArrayRef.h"
21 #include <system_error>
27 class DiagnosticConsumer;
31 enum class ParseError { Success = 0, Error, Unsuitable };
32 class ParseErrorCategory final : public std::error_category {
34 const char *name() const LLVM_NOEXCEPT override;
35 std::string message(int EV) const override;
37 const std::error_category &getParseCategory();
38 std::error_code make_error_code(ParseError e);
40 /// \brief The \c FormatStyle is used to configure the formatting to follow
41 /// specific guidelines.
43 /// \brief Supported languages. When stored in a configuration file, specifies
44 /// the language, that the configuration targets. When passed to the
45 /// reformat() function, enables syntax features specific to the language.
49 /// Should be used for C, C++, ObjectiveC, ObjectiveC++.
51 /// Should be used for Java.
53 /// Should be used for JavaScript.
55 /// Should be used for Protocol Buffers
56 /// (https://developers.google.com/protocol-buffers/).
60 /// \brief Language, this format style is targeted at.
61 LanguageKind Language;
63 /// \brief The column limit.
65 /// A column limit of \c 0 means that there is no column limit. In this case,
66 /// clang-format will respect the input's line breaking decisions within
67 /// statements unless they contradict other rules.
70 /// \brief The maximum number of consecutive empty lines to keep.
71 unsigned MaxEmptyLinesToKeep;
73 /// \brief If true, empty lines at the start of blocks are kept.
74 bool KeepEmptyLinesAtTheStartOfBlocks;
76 /// \brief The penalty for each line break introduced inside a comment.
77 unsigned PenaltyBreakComment;
79 /// \brief The penalty for each line break introduced inside a string literal.
80 unsigned PenaltyBreakString;
82 /// \brief The penalty for each character outside of the column limit.
83 unsigned PenaltyExcessCharacter;
85 /// \brief The penalty for breaking before the first \c <<.
86 unsigned PenaltyBreakFirstLessLess;
88 /// \brief The penalty for breaking a function call after "call(".
89 unsigned PenaltyBreakBeforeFirstCallParameter;
91 /// \brief The & and * alignment style.
92 enum PointerAlignmentStyle {
93 /// Align pointer to the left.
95 /// Align pointer to the right.
97 /// Align pointer in the middle.
101 /// Pointer and reference alignment style.
102 PointerAlignmentStyle PointerAlignment;
104 /// \brief If \c true, analyze the formatted file for the most common
105 /// alignment of & and *. \c PointerAlignment is then used only as fallback.
106 bool DerivePointerAlignment;
108 /// \brief The extra indent or outdent of access modifiers, e.g. \c public:.
109 int AccessModifierOffset;
111 /// \brief Supported language standards.
112 enum LanguageStandard {
113 /// Use C++03-compatible syntax.
115 /// Use features of C++11 (e.g. \c A<A<int>> instead of
116 /// <tt>A<A<int> ></tt>).
118 /// Automatic detection based on the input.
122 /// \brief Format compatible with this standard, e.g. use
123 /// <tt>A<A<int> ></tt> instead of \c A<A<int>> for LS_Cpp03.
124 LanguageStandard Standard;
126 /// \brief Indent case labels one level from the switch statement.
128 /// When \c false, use the same indentation level as for the switch statement.
129 /// Switch statement body is always indented one level more than case labels.
130 bool IndentCaseLabels;
132 /// \brief Indent if a function definition or declaration is wrapped after the
134 bool IndentWrappedFunctionNames;
136 /// \brief Different ways to indent namespace contents.
137 enum NamespaceIndentationKind {
138 /// Don't indent in namespaces.
140 /// Indent only in inner namespaces (nested in other namespaces).
142 /// Indent in all namespaces.
146 /// \brief The indentation used for namespaces.
147 NamespaceIndentationKind NamespaceIndentation;
149 /// \brief The number of spaces before trailing line comments
150 /// (\c // - comments).
152 /// This does not affect trailing block comments (\c /**/ - comments) as those
153 /// commonly have different usage patterns and a number of special cases.
154 unsigned SpacesBeforeTrailingComments;
156 /// \brief If \c false, a function declaration's or function definition's
157 /// parameters will either all be on the same line or will have one line each.
158 bool BinPackParameters;
160 /// \brief If \c false, a function call's arguments will either be all on the
161 /// same line or will have one line each.
162 bool BinPackArguments;
164 /// \brief If \c true, clang-format detects whether function calls and
165 /// definitions are formatted with one parameter per line.
167 /// Each call can be bin-packed, one-per-line or inconclusive. If it is
168 /// inconclusive, e.g. completely on one line, but a decision needs to be
169 /// made, clang-format analyzes whether there are other bin-packed cases in
170 /// the input file and act accordingly.
172 /// NOTE: This is an experimental flag, that might go away or be renamed. Do
173 /// not use this in config files, etc. Use at your own risk.
174 bool ExperimentalAutoDetectBinPacking;
176 /// \brief Allow putting all parameters of a function declaration onto
177 /// the next line even if \c BinPackParameters is \c false.
178 bool AllowAllParametersOfDeclarationOnNextLine;
180 /// \brief Penalty for putting the return type of a function onto its own
182 unsigned PenaltyReturnTypeOnItsOwnLine;
184 /// \brief If the constructor initializers don't fit on a line, put each
185 /// initializer on its own line.
186 bool ConstructorInitializerAllOnOneLineOrOnePerLine;
188 /// \brief Always break constructor initializers before commas and align
189 /// the commas with the colon.
190 bool BreakConstructorInitializersBeforeComma;
192 /// \brief Allows contracting simple braced statements to a single line.
194 /// E.g., this allows <tt>if (a) { return; }</tt> to be put on a single line.
195 bool AllowShortBlocksOnASingleLine;
197 /// \brief If \c true, <tt>if (a) return;</tt> can be put on a single
199 bool AllowShortIfStatementsOnASingleLine;
201 /// \brief If \c true, <tt>while (true) continue;</tt> can be put on a
203 bool AllowShortLoopsOnASingleLine;
205 /// \brief If \c true, short case labels will be contracted to a single line.
206 bool AllowShortCaseLabelsOnASingleLine;
208 /// \brief Different styles for merging short functions containing at most one
210 enum ShortFunctionStyle {
211 /// \brief Never merge functions into a single line.
213 /// \brief Only merge functions defined inside a class.
215 /// \brief Only merge empty functions.
217 /// \brief Merge all functions fitting on a single line.
221 /// \brief Dependent on the value, <tt>int f() { return 0; }</tt> can be put
222 /// on a single line.
223 ShortFunctionStyle AllowShortFunctionsOnASingleLine;
225 /// \brief Add a space after \c @property in Objective-C, i.e. use
226 /// <tt>\@property (readonly)</tt> instead of <tt>\@property(readonly)</tt>.
227 bool ObjCSpaceAfterProperty;
229 /// \brief Add a space in front of an Objective-C protocol list, i.e. use
230 /// <tt>Foo <Protocol></tt> instead of \c Foo<Protocol>.
231 bool ObjCSpaceBeforeProtocolList;
233 /// \brief If \c true, horizontally aligns arguments after an open bracket.
235 /// This applies to round brackets (parentheses), angle brackets and square
236 /// brackets. This will result in formattings like
238 /// someLongFunction(argument1,
241 bool AlignAfterOpenBracket;
243 /// \brief If \c true, horizontally align operands of binary and ternary
247 /// \brief If \c true, aligns trailing comments.
248 bool AlignTrailingComments;
250 /// \brief If \c true, aligns consecutive assignments.
252 /// This will align the assignment operators of consecutive lines. This
253 /// will result in formattings like
259 bool AlignConsecutiveAssignments;
261 /// \brief If \c true, aligns escaped newlines as far left as possible.
262 /// Otherwise puts them into the right-most column.
263 bool AlignEscapedNewlinesLeft;
265 /// \brief The number of columns to use for indentation.
266 unsigned IndentWidth;
268 /// \brief The number of columns used for tab stops.
271 /// \brief The number of characters to use for indentation of constructor
272 /// initializer lists.
273 unsigned ConstructorInitializerIndentWidth;
275 /// \brief The number of characters to use for indentation of ObjC blocks.
276 unsigned ObjCBlockIndentWidth;
278 /// \brief If \c true, always break after function definition return types.
280 /// More truthfully called 'break before the identifier following the type
281 /// in a function definition'. PenaltyReturnTypeOnItsOwnLine becomes
283 bool AlwaysBreakAfterDefinitionReturnType;
285 /// \brief If \c true, always break after the <tt>template<...></tt> of a
286 /// template declaration.
287 bool AlwaysBreakTemplateDeclarations;
289 /// \brief If \c true, always break before multiline string literals.
290 bool AlwaysBreakBeforeMultilineStrings;
292 /// \brief Different ways to use tab in formatting.
296 /// Use tabs only for indentation.
298 /// Use tabs whenever we need to fill whitespace that spans at least from
299 /// one tab stop to the next one.
303 /// \brief The way to use tab characters in the resulting file.
306 /// \brief The style of breaking before or after binary operators.
307 enum BinaryOperatorStyle {
308 /// Break after operators.
310 /// Break before operators that aren't assignments.
312 /// Break before operators.
316 /// \brief The way to wrap binary operators.
317 BinaryOperatorStyle BreakBeforeBinaryOperators;
319 /// \brief If \c true, ternary operators will be placed after line breaks.
320 bool BreakBeforeTernaryOperators;
322 /// \brief Different ways to attach braces to their surrounding context.
323 enum BraceBreakingStyle {
324 /// Always attach braces to surrounding context.
326 /// Like \c Attach, but break before braces on function, namespace and
327 /// class definitions.
329 /// Like \c Attach, but break before function definitions, and 'else'.
331 /// Always break before braces.
333 /// Always break before braces and add an extra level of indentation to
334 /// braces of control statements, not to those of class, function
335 /// or other definitions.
339 /// \brief The brace breaking style to use.
340 BraceBreakingStyle BreakBeforeBraces;
342 /// \brief If \c true, format braced lists as best suited for C++11 braced
345 /// Important differences:
346 /// - No spaces inside the braced list.
347 /// - No line break before the closing brace.
348 /// - Indentation with the continuation indent, not with the block indent.
350 /// Fundamentally, C++11 braced lists are formatted exactly like function
351 /// calls would be formatted in their place. If the braced list follows a name
352 /// (e.g. a type or variable name), clang-format formats as if the \c {} were
353 /// the parentheses of a function call with that name. If there is no name,
354 /// a zero-length name is assumed.
355 bool Cpp11BracedListStyle;
357 /// \brief If \c true, spaces will be inserted after '(' and before ')'.
358 bool SpacesInParentheses;
360 /// \brief If \c true, spaces will be inserted after '<' and before '>' in
361 /// template argument lists
364 /// \brief If \c true, spaces will be inserted after '[' and before ']'.
365 bool SpacesInSquareBrackets;
367 /// \brief If \c true, spaces may be inserted into '()'.
368 bool SpaceInEmptyParentheses;
370 /// \brief If \c true, spaces are inserted inside container literals (e.g.
371 /// ObjC and Javascript array and dict literals).
372 bool SpacesInContainerLiterals;
374 /// \brief If \c true, spaces may be inserted into C style casts.
375 bool SpacesInCStyleCastParentheses;
377 /// \brief If \c true, a space may be inserted after C style casts.
378 bool SpaceAfterCStyleCast;
380 /// \brief Different ways to put a space before opening parentheses.
381 enum SpaceBeforeParensOptions {
382 /// Never put a space before opening parentheses.
384 /// Put a space before opening parentheses only after control statement
385 /// keywords (<tt>for/if/while...</tt>).
386 SBPO_ControlStatements,
387 /// Always put a space before opening parentheses, except when it's
388 /// prohibited by the syntax rules (in function-like macro definitions) or
389 /// when determined by other style rules (after unary operators, opening
390 /// parentheses, etc.)
394 /// \brief Defines in which cases to put a space before opening parentheses.
395 SpaceBeforeParensOptions SpaceBeforeParens;
397 /// \brief If \c false, spaces will be removed before assignment operators.
398 bool SpaceBeforeAssignmentOperators;
400 /// \brief Indent width for line continuations.
401 unsigned ContinuationIndentWidth;
403 /// \brief A regular expression that describes comments with special meaning,
404 /// which should not be split into lines or otherwise changed.
405 std::string CommentPragmas;
407 /// \brief Disables formatting at all.
410 /// \brief A vector of macros that should be interpreted as foreach loops
411 /// instead of as function calls.
413 /// These are expected to be macros of the form:
415 /// FOREACH(<variable-declaration>, ...)
419 /// For example: BOOST_FOREACH.
420 std::vector<std::string> ForEachMacros;
422 bool operator==(const FormatStyle &R) const {
423 return AccessModifierOffset == R.AccessModifierOffset &&
424 AlignAfterOpenBracket == R.AlignAfterOpenBracket &&
425 AlignOperands == R.AlignOperands &&
426 AlignEscapedNewlinesLeft == R.AlignEscapedNewlinesLeft &&
427 AlignTrailingComments == R.AlignTrailingComments &&
428 AllowAllParametersOfDeclarationOnNextLine ==
429 R.AllowAllParametersOfDeclarationOnNextLine &&
430 AllowShortFunctionsOnASingleLine ==
431 R.AllowShortFunctionsOnASingleLine &&
432 AllowShortBlocksOnASingleLine == R.AllowShortBlocksOnASingleLine &&
433 AllowShortIfStatementsOnASingleLine ==
434 R.AllowShortIfStatementsOnASingleLine &&
435 AllowShortLoopsOnASingleLine == R.AllowShortLoopsOnASingleLine &&
436 AlwaysBreakAfterDefinitionReturnType ==
437 R.AlwaysBreakAfterDefinitionReturnType &&
438 AlwaysBreakTemplateDeclarations ==
439 R.AlwaysBreakTemplateDeclarations &&
440 AlwaysBreakBeforeMultilineStrings ==
441 R.AlwaysBreakBeforeMultilineStrings &&
442 BinPackParameters == R.BinPackParameters &&
443 BinPackArguments == R.BinPackArguments &&
444 BreakBeforeBinaryOperators == R.BreakBeforeBinaryOperators &&
445 BreakBeforeTernaryOperators == R.BreakBeforeTernaryOperators &&
446 BreakBeforeBraces == R.BreakBeforeBraces &&
447 BreakConstructorInitializersBeforeComma ==
448 R.BreakConstructorInitializersBeforeComma &&
449 ColumnLimit == R.ColumnLimit &&
450 ConstructorInitializerAllOnOneLineOrOnePerLine ==
451 R.ConstructorInitializerAllOnOneLineOrOnePerLine &&
452 ConstructorInitializerIndentWidth ==
453 R.ConstructorInitializerIndentWidth &&
454 DerivePointerAlignment == R.DerivePointerAlignment &&
455 ExperimentalAutoDetectBinPacking ==
456 R.ExperimentalAutoDetectBinPacking &&
457 IndentCaseLabels == R.IndentCaseLabels &&
458 IndentWrappedFunctionNames == R.IndentWrappedFunctionNames &&
459 IndentWidth == R.IndentWidth && Language == R.Language &&
460 MaxEmptyLinesToKeep == R.MaxEmptyLinesToKeep &&
461 KeepEmptyLinesAtTheStartOfBlocks ==
462 R.KeepEmptyLinesAtTheStartOfBlocks &&
463 NamespaceIndentation == R.NamespaceIndentation &&
464 ObjCBlockIndentWidth == R.ObjCBlockIndentWidth &&
465 ObjCSpaceAfterProperty == R.ObjCSpaceAfterProperty &&
466 ObjCSpaceBeforeProtocolList == R.ObjCSpaceBeforeProtocolList &&
467 PenaltyBreakComment == R.PenaltyBreakComment &&
468 PenaltyBreakFirstLessLess == R.PenaltyBreakFirstLessLess &&
469 PenaltyBreakString == R.PenaltyBreakString &&
470 PenaltyExcessCharacter == R.PenaltyExcessCharacter &&
471 PenaltyReturnTypeOnItsOwnLine == R.PenaltyReturnTypeOnItsOwnLine &&
472 PointerAlignment == R.PointerAlignment &&
473 SpacesBeforeTrailingComments == R.SpacesBeforeTrailingComments &&
474 Cpp11BracedListStyle == R.Cpp11BracedListStyle &&
475 Standard == R.Standard && TabWidth == R.TabWidth &&
476 UseTab == R.UseTab && SpacesInParentheses == R.SpacesInParentheses &&
477 SpacesInSquareBrackets == R.SpacesInSquareBrackets &&
478 SpacesInAngles == R.SpacesInAngles &&
479 SpaceInEmptyParentheses == R.SpaceInEmptyParentheses &&
480 SpacesInContainerLiterals == R.SpacesInContainerLiterals &&
481 SpacesInCStyleCastParentheses == R.SpacesInCStyleCastParentheses &&
482 SpaceAfterCStyleCast == R.SpaceAfterCStyleCast &&
483 SpaceBeforeParens == R.SpaceBeforeParens &&
484 SpaceBeforeAssignmentOperators == R.SpaceBeforeAssignmentOperators &&
485 ContinuationIndentWidth == R.ContinuationIndentWidth &&
486 CommentPragmas == R.CommentPragmas &&
487 ForEachMacros == R.ForEachMacros;
491 /// \brief Returns a format style complying with the LLVM coding standards:
492 /// http://llvm.org/docs/CodingStandards.html.
493 FormatStyle getLLVMStyle();
495 /// \brief Returns a format style complying with one of Google's style guides:
496 /// http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml.
497 /// http://google-styleguide.googlecode.com/svn/trunk/javascriptguide.xml.
498 /// https://developers.google.com/protocol-buffers/docs/style.
499 FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language);
501 /// \brief Returns a format style complying with Chromium's style guide:
502 /// http://www.chromium.org/developers/coding-style.
503 FormatStyle getChromiumStyle(FormatStyle::LanguageKind Language);
505 /// \brief Returns a format style complying with Mozilla's style guide:
506 /// https://developer.mozilla.org/en-US/docs/Developer_Guide/Coding_Style.
507 FormatStyle getMozillaStyle();
509 /// \brief Returns a format style complying with Webkit's style guide:
510 /// http://www.webkit.org/coding/coding-style.html
511 FormatStyle getWebKitStyle();
513 /// \brief Returns a format style complying with GNU Coding Standards:
514 /// http://www.gnu.org/prep/standards/standards.html
515 FormatStyle getGNUStyle();
517 /// \brief Returns style indicating formatting should be not applied at all.
518 FormatStyle getNoStyle();
520 /// \brief Gets a predefined style for the specified language by name.
522 /// Currently supported names: LLVM, Google, Chromium, Mozilla. Names are
523 /// compared case-insensitively.
525 /// Returns \c true if the Style has been set.
526 bool getPredefinedStyle(StringRef Name, FormatStyle::LanguageKind Language,
529 /// \brief Parse configuration from YAML-formatted text.
531 /// Style->Language is used to get the base style, if the \c BasedOnStyle
532 /// option is present.
534 /// When \c BasedOnStyle is not present, options not present in the YAML
535 /// document, are retained in \p Style.
536 std::error_code parseConfiguration(StringRef Text, FormatStyle *Style);
538 /// \brief Gets configuration in a YAML string.
539 std::string configurationAsText(const FormatStyle &Style);
541 /// \brief Reformats the given \p Ranges in the file \p ID.
543 /// Each range is extended on either end to its next bigger logic unit, i.e.
544 /// everything that might influence its formatting or might be influenced by its
547 /// Returns the \c Replacements necessary to make all \p Ranges comply with
550 /// If \c IncompleteFormat is non-null, its value will be set to true if any
551 /// of the affected ranges were not formatted due to a non-recoverable syntax
553 tooling::Replacements reformat(const FormatStyle &Style,
554 SourceManager &SourceMgr, FileID ID,
555 ArrayRef<CharSourceRange> Ranges,
556 bool *IncompleteFormat = nullptr);
558 /// \brief Reformats the given \p Ranges in \p Code.
560 /// Otherwise identical to the reformat() function using a file ID.
561 tooling::Replacements reformat(const FormatStyle &Style, StringRef Code,
562 ArrayRef<tooling::Range> Ranges,
563 StringRef FileName = "<stdin>",
564 bool *IncompleteFormat = nullptr);
566 /// \brief Returns the \c LangOpts that the formatter expects you to set.
568 /// \param Style determines specific settings for lexing mode.
569 LangOptions getFormattingLangOpts(const FormatStyle &Style = getLLVMStyle());
571 /// \brief Description to be used for help text for a llvm::cl option for
572 /// specifying format style. The description is closely related to the operation
574 extern const char *StyleOptionHelpDescription;
576 /// \brief Construct a FormatStyle based on \c StyleName.
578 /// \c StyleName can take several forms:
579 /// \li "{<key>: <value>, ...}" - Set specic style parameters.
580 /// \li "<style name>" - One of the style names supported by
581 /// getPredefinedStyle().
582 /// \li "file" - Load style configuration from a file called '.clang-format'
583 /// located in one of the parent directories of \c FileName or the current
584 /// directory if \c FileName is empty.
586 /// \param[in] StyleName Style name to interpret according to the description
588 /// \param[in] FileName Path to start search for .clang-format if \c StyleName
590 /// \param[in] FallbackStyle The name of a predefined style used to fallback to
591 /// in case the style can't be determined from \p StyleName.
593 /// \returns FormatStyle as specified by \c StyleName. If no style could be
594 /// determined, the default is LLVM Style (see getLLVMStyle()).
595 FormatStyle getStyle(StringRef StyleName, StringRef FileName,
596 StringRef FallbackStyle);
598 } // end namespace format
599 } // end namespace clang
603 struct is_error_code_enum<clang::format::ParseError> : std::true_type {};
606 #endif // LLVM_CLANG_FORMAT_FORMAT_H