1 //===--- FormatToken.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 /// \brief This file contains the declaration of the FormatToken, a wrapper
12 /// around Token with additional information related to formatting.
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_CLANG_FORMAT_FORMAT_TOKEN_H
17 #define LLVM_CLANG_FORMAT_FORMAT_TOKEN_H
19 #include "clang/Basic/OperatorPrecedence.h"
20 #include "clang/Format/Format.h"
21 #include "clang/Lex/Lexer.h"
28 TT_ArrayInitializerLSquare,
29 TT_ArraySubscriptLSquare,
36 TT_ConflictAlternative,
39 TT_CtorInitializerColon,
40 TT_CtorInitializerComma,
41 TT_DesignatedInitializerPeriod,
43 TT_FunctionDeclarationName,
45 TT_FunctionTypeLParen,
46 TT_ImplicitStringLiteral,
56 TT_ObjCMethodSpecifier,
58 TT_OverloadedOperator,
59 TT_OverloadedOperatorLParen,
60 TT_PointerOrReference,
61 TT_PureVirtualSpecifier,
62 TT_RangeBasedForLoopColon,
68 TT_TrailingAnnotation,
69 TT_TrailingReturnArrow,
70 TT_TrailingUnaryOperator,
75 // Represents what type of block a set of braces open.
82 // The packing kind of a function's parameters.
83 enum ParameterPackingKind {
98 /// \brief A wrapper around a \c Token storing information about the
99 /// whitespace characters preceding it.
102 : NewlinesBefore(0), HasUnescapedNewline(false), LastNewlineOffset(0),
103 ColumnWidth(0), LastLineColumnWidth(0), IsMultiline(false),
104 IsFirst(false), MustBreakBefore(false), IsUnterminatedLiteral(false),
105 BlockKind(BK_Unknown), Type(TT_Unknown), SpacesRequiredBefore(0),
106 CanBreakBefore(false), ClosesTemplateDeclaration(false),
107 ParameterCount(0), BlockParameterCount(0),
108 PackingKind(PPK_Inconclusive), TotalLength(0), UnbreakableTailLength(0),
109 BindingStrength(0), NestingLevel(0), SplitPenalty(0),
110 LongestObjCSelectorName(0), FakeRParens(0),
111 StartsBinaryExpression(false), EndsBinaryExpression(false),
112 OperatorIndex(0), LastOperator(false),
113 PartOfMultiVariableDeclStmt(false), IsForEachMacro(false),
114 MatchingParen(nullptr), Previous(nullptr), Next(nullptr),
115 Decision(FD_Unformatted), Finalized(false) {}
117 /// \brief The \c Token.
120 /// \brief The number of newlines immediately before the \c Token.
122 /// This can be used to determine what the user wrote in the original code
123 /// and thereby e.g. leave an empty line between two function definitions.
124 unsigned NewlinesBefore;
126 /// \brief Whether there is at least one unescaped newline before the \c
128 bool HasUnescapedNewline;
130 /// \brief The range of the whitespace immediately preceding the \c Token.
131 SourceRange WhitespaceRange;
133 /// \brief The offset just past the last '\n' in this token's leading
134 /// whitespace (relative to \c WhiteSpaceStart). 0 if there is no '\n'.
135 unsigned LastNewlineOffset;
137 /// \brief The width of the non-whitespace parts of the token (or its first
138 /// line for multi-line tokens) in columns.
139 /// We need this to correctly measure number of columns a token spans.
140 unsigned ColumnWidth;
142 /// \brief Contains the width in columns of the last line of a multi-line
144 unsigned LastLineColumnWidth;
146 /// \brief Whether the token text contains newlines (escaped or not).
149 /// \brief Indicates that this is the first token.
152 /// \brief Whether there must be a line break before this token.
154 /// This happens for example when a preprocessor directive ended directly
155 /// before the token.
156 bool MustBreakBefore;
158 /// \brief Returns actual token start location without leading escaped
159 /// newlines and whitespace.
161 /// This can be different to Tok.getLocation(), which includes leading escaped
163 SourceLocation getStartOfNonWhitespace() const {
164 return WhitespaceRange.getEnd();
167 /// \brief The raw text of the token.
169 /// Contains the raw token text without leading whitespace and without leading
170 /// escaped newlines.
173 /// \brief Set to \c true if this token is an unterminated literal.
174 bool IsUnterminatedLiteral;
176 /// \brief Contains the kind of block if this token is a brace.
177 BraceBlockKind BlockKind;
181 /// \brief The number of spaces that should be inserted before this token.
182 unsigned SpacesRequiredBefore;
184 /// \brief \c true if it is allowed to break before this token.
187 bool ClosesTemplateDeclaration;
189 /// \brief Number of parameters, if this is "(", "[" or "<".
191 /// This is initialized to 1 as we don't need to distinguish functions with
192 /// 0 parameters from functions with 1 parameter. Thus, we can simply count
193 /// the number of commas.
194 unsigned ParameterCount;
196 /// \brief Number of parameters that are nested blocks,
197 /// if this is "(", "[" or "<".
198 unsigned BlockParameterCount;
200 /// \brief A token can have a special role that can carry extra information
201 /// about the token's formatting.
202 std::unique_ptr<TokenRole> Role;
204 /// \brief If this is an opening parenthesis, how are the parameters packed?
205 ParameterPackingKind PackingKind;
207 /// \brief The total length of the unwrapped line up to and including this
209 unsigned TotalLength;
211 /// \brief The original 0-based column of this token, including expanded tabs.
212 /// The configured TabWidth is used as tab width.
213 unsigned OriginalColumn;
215 /// \brief The length of following tokens until the next natural split point,
216 /// or the next token that can be broken.
217 unsigned UnbreakableTailLength;
219 // FIXME: Come up with a 'cleaner' concept.
220 /// \brief The binding strength of a token. This is a combined value of
221 /// operator precedence, parenthesis nesting, etc.
222 unsigned BindingStrength;
224 /// \brief The nesting level of this token, i.e. the number of surrounding (),
226 unsigned NestingLevel;
228 /// \brief Penalty for inserting a line break before this token.
229 unsigned SplitPenalty;
231 /// \brief If this is the first ObjC selector name in an ObjC method
232 /// definition or call, this contains the length of the longest name.
234 /// This being set to 0 means that the selectors should not be colon-aligned,
235 /// e.g. because several of them are block-type.
236 unsigned LongestObjCSelectorName;
238 /// \brief Stores the number of required fake parentheses and the
239 /// corresponding operator precedence.
241 /// If multiple fake parentheses start at a token, this vector stores them in
242 /// reverse order, i.e. inner fake parenthesis first.
243 SmallVector<prec::Level, 4> FakeLParens;
244 /// \brief Insert this many fake ) after this token for correct indentation.
245 unsigned FakeRParens;
247 /// \brief \c true if this token starts a binary expression, i.e. has at least
248 /// one fake l_paren with a precedence greater than prec::Unknown.
249 bool StartsBinaryExpression;
250 /// \brief \c true if this token ends a binary expression.
251 bool EndsBinaryExpression;
253 /// \brief Is this is an operator (or "."/"->") in a sequence of operators
254 /// with the same precedence, contains the 0-based operator index.
255 unsigned OperatorIndex;
257 /// \brief Is this the last operator (or "."/"->") in a sequence of operators
258 /// with the same precedence?
261 /// \brief Is this token part of a \c DeclStmt defining multiple variables?
263 /// Only set if \c Type == \c TT_StartOfName.
264 bool PartOfMultiVariableDeclStmt;
266 /// \brief Is this a foreach macro?
269 bool is(tok::TokenKind Kind) const { return Tok.is(Kind); }
271 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const {
272 return is(K1) || is(K2);
275 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, tok::TokenKind K3) const {
276 return is(K1) || is(K2) || is(K3);
279 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, tok::TokenKind K3,
280 tok::TokenKind K4, tok::TokenKind K5 = tok::NUM_TOKENS,
281 tok::TokenKind K6 = tok::NUM_TOKENS,
282 tok::TokenKind K7 = tok::NUM_TOKENS,
283 tok::TokenKind K8 = tok::NUM_TOKENS,
284 tok::TokenKind K9 = tok::NUM_TOKENS,
285 tok::TokenKind K10 = tok::NUM_TOKENS,
286 tok::TokenKind K11 = tok::NUM_TOKENS,
287 tok::TokenKind K12 = tok::NUM_TOKENS) const {
288 return is(K1) || is(K2) || is(K3) || is(K4) || is(K5) || is(K6) || is(K7) ||
289 is(K8) || is(K9) || is(K10) || is(K11) || is(K12);
292 bool isNot(tok::TokenKind Kind) const { return Tok.isNot(Kind); }
293 bool isStringLiteral() const { return tok::isStringLiteral(Tok.getKind()); }
295 bool isObjCAtKeyword(tok::ObjCKeywordKind Kind) const {
296 return Tok.isObjCAtKeyword(Kind);
299 bool isAccessSpecifier(bool ColonRequired = true) const {
300 return isOneOf(tok::kw_public, tok::kw_protected, tok::kw_private) &&
301 (!ColonRequired || (Next && Next->is(tok::colon)));
304 /// \brief Determine whether the token is a simple-type-specifier.
305 bool isSimpleTypeSpecifier() const;
307 bool isObjCAccessSpecifier() const {
308 return is(tok::at) && Next && (Next->isObjCAtKeyword(tok::objc_public) ||
309 Next->isObjCAtKeyword(tok::objc_protected) ||
310 Next->isObjCAtKeyword(tok::objc_package) ||
311 Next->isObjCAtKeyword(tok::objc_private));
314 /// \brief Returns whether \p Tok is ([{ or a template opening <.
315 bool opensScope() const {
316 return isOneOf(tok::l_paren, tok::l_brace, tok::l_square) ||
317 Type == TT_TemplateOpener;
319 /// \brief Returns whether \p Tok is )]} or a template closing >.
320 bool closesScope() const {
321 return isOneOf(tok::r_paren, tok::r_brace, tok::r_square) ||
322 Type == TT_TemplateCloser;
325 /// \brief Returns \c true if this is a "." or "->" accessing a member.
326 bool isMemberAccess() const {
327 return isOneOf(tok::arrow, tok::period, tok::arrowstar) &&
328 Type != TT_DesignatedInitializerPeriod;
331 bool isUnaryOperator() const {
332 switch (Tok.getKind()) {
336 case tok::minusminus:
340 case tok::kw_alignof:
347 bool isBinaryOperator() const {
348 // Comma is a binary operator, but does not behave as such wrt. formatting.
349 return getPrecedence() > prec::Comma;
352 bool isTrailingComment() const {
353 return is(tok::comment) && (!Next || Next->NewlinesBefore > 0);
356 prec::Level getPrecedence() const {
357 return getBinOpPrecedence(Tok.getKind(), true, true);
360 /// \brief Returns the previous token ignoring comments.
361 FormatToken *getPreviousNonComment() const {
362 FormatToken *Tok = Previous;
363 while (Tok && Tok->is(tok::comment))
368 /// \brief Returns the next token ignoring comments.
369 const FormatToken *getNextNonComment() const {
370 const FormatToken *Tok = Next;
371 while (Tok && Tok->is(tok::comment))
376 /// \brief Returns \c true if this tokens starts a block-type list, i.e. a
377 /// list that should be indented with a block indent.
378 bool opensBlockTypeList(const FormatStyle &Style) const {
379 return Type == TT_ArrayInitializerLSquare ||
381 (BlockKind == BK_Block || Type == TT_DictLiteral ||
382 !Style.Cpp11BracedListStyle));
385 /// \brief Same as opensBlockTypeList, but for the closing token.
386 bool closesBlockTypeList(const FormatStyle &Style) const {
387 return MatchingParen && MatchingParen->opensBlockTypeList(Style);
390 FormatToken *MatchingParen;
392 FormatToken *Previous;
395 SmallVector<AnnotatedLine *, 1> Children;
397 /// \brief Stores the formatting decision for the token once it was made.
398 FormatDecision Decision;
400 /// \brief If \c true, this token has been fully formatted (indented and
401 /// potentially re-formatted inside), and we do not allow further formatting
407 FormatToken(const FormatToken &) LLVM_DELETED_FUNCTION;
408 void operator=(const FormatToken &) LLVM_DELETED_FUNCTION;
411 class ContinuationIndenter;
416 TokenRole(const FormatStyle &Style) : Style(Style) {}
417 virtual ~TokenRole();
419 /// \brief After the \c TokenAnnotator has finished annotating all the tokens,
420 /// this function precomputes required information for formatting.
421 virtual void precomputeFormattingInfos(const FormatToken *Token);
423 /// \brief Apply the special formatting that the given role demands.
425 /// Assumes that the token having this role is already formatted.
427 /// Continues formatting from \p State leaving indentation to \p Indenter and
428 /// returns the total penalty that this formatting incurs.
429 virtual unsigned formatFromToken(LineState &State,
430 ContinuationIndenter *Indenter,
435 /// \brief Same as \c formatFromToken, but assumes that the first token has
436 /// already been set thereby deciding on the first line break.
437 virtual unsigned formatAfterToken(LineState &State,
438 ContinuationIndenter *Indenter,
443 /// \brief Notifies the \c Role that a comma was found.
444 virtual void CommaFound(const FormatToken *Token) {}
447 const FormatStyle &Style;
450 class CommaSeparatedList : public TokenRole {
452 CommaSeparatedList(const FormatStyle &Style)
453 : TokenRole(Style), HasNestedBracedList(false) {}
455 void precomputeFormattingInfos(const FormatToken *Token) override;
457 unsigned formatAfterToken(LineState &State, ContinuationIndenter *Indenter,
458 bool DryRun) override;
460 unsigned formatFromToken(LineState &State, ContinuationIndenter *Indenter,
461 bool DryRun) override;
463 /// \brief Adds \p Token as the next comma to the \c CommaSeparated list.
464 void CommaFound(const FormatToken *Token) override {
465 Commas.push_back(Token);
469 /// \brief A struct that holds information on how to format a given list with
470 /// a specific number of columns.
471 struct ColumnFormat {
472 /// \brief The number of columns to use.
475 /// \brief The total width in characters.
478 /// \brief The number of lines required for this format.
481 /// \brief The size of each column in characters.
482 SmallVector<unsigned, 8> ColumnSizes;
485 /// \brief Calculate which \c ColumnFormat fits best into
486 /// \p RemainingCharacters.
487 const ColumnFormat *getColumnFormat(unsigned RemainingCharacters) const;
489 /// \brief The ordered \c FormatTokens making up the commas of this list.
490 SmallVector<const FormatToken *, 8> Commas;
492 /// \brief The length of each of the list's items in characters including the
494 SmallVector<unsigned, 8> ItemLengths;
496 /// \brief Precomputed formats that can be used for this list.
497 SmallVector<ColumnFormat, 4> Formats;
499 bool HasNestedBracedList;
502 } // namespace format
505 #endif // LLVM_CLANG_FORMAT_FORMAT_TOKEN_H