| //===--- WhitespaceManager.h - Format C++ code ------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// WhitespaceManager class manages whitespace around tokens and their |
| /// replacements. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_LIB_FORMAT_WHITESPACEMANAGER_H |
| #define LLVM_CLANG_LIB_FORMAT_WHITESPACEMANAGER_H |
| |
| #include "TokenAnnotator.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Format/Format.h" |
| #include <string> |
| |
| namespace clang { |
| namespace format { |
| |
| /// Manages the whitespaces around tokens and their replacements. |
| /// |
| /// This includes special handling for certain constructs, e.g. the alignment of |
| /// trailing line comments. |
| /// |
| /// To guarantee correctness of alignment operations, the \c WhitespaceManager |
| /// must be informed about every token in the source file; for each token, there |
| /// must be exactly one call to either \c replaceWhitespace or |
| /// \c addUntouchableToken. |
| /// |
| /// There may be multiple calls to \c breakToken for a given token. |
| class WhitespaceManager { |
| public: |
| WhitespaceManager(const SourceManager &SourceMgr, const FormatStyle &Style, |
| bool UseCRLF) |
| : SourceMgr(SourceMgr), Style(Style), UseCRLF(UseCRLF) {} |
| |
| bool useCRLF() const { return UseCRLF; } |
| |
| /// Replaces the whitespace in front of \p Tok. Only call once for |
| /// each \c AnnotatedToken. |
| /// |
| /// \p StartOfTokenColumn is the column at which the token will start after |
| /// this replacement. It is needed for determining how \p Spaces is turned |
| /// into tabs and spaces for some format styles. |
| void replaceWhitespace(FormatToken &Tok, unsigned Newlines, unsigned Spaces, |
| unsigned StartOfTokenColumn, |
| bool InPPDirective = false); |
| |
| /// Adds information about an unchangeable token's whitespace. |
| /// |
| /// Needs to be called for every token for which \c replaceWhitespace |
| /// was not called. |
| void addUntouchableToken(const FormatToken &Tok, bool InPPDirective); |
| |
| llvm::Error addReplacement(const tooling::Replacement &Replacement); |
| |
| /// Inserts or replaces whitespace in the middle of a token. |
| /// |
| /// Inserts \p PreviousPostfix, \p Newlines, \p Spaces and \p CurrentPrefix |
| /// (in this order) at \p Offset inside \p Tok, replacing \p ReplaceChars |
| /// characters. |
| /// |
| /// Note: \p Spaces can be negative to retain information about initial |
| /// relative column offset between a line of a block comment and the start of |
| /// the comment. This negative offset may be compensated by trailing comment |
| /// alignment here. In all other cases negative \p Spaces will be truncated to |
| /// 0. |
| /// |
| /// When \p InPPDirective is true, escaped newlines are inserted. \p Spaces is |
| /// used to align backslashes correctly. |
| void replaceWhitespaceInToken(const FormatToken &Tok, unsigned Offset, |
| unsigned ReplaceChars, |
| StringRef PreviousPostfix, |
| StringRef CurrentPrefix, bool InPPDirective, |
| unsigned Newlines, int Spaces); |
| |
| /// Returns all the \c Replacements created during formatting. |
| const tooling::Replacements &generateReplacements(); |
| |
| /// Represents a change before a token, a break inside a token, |
| /// or the layout of an unchanged token (or whitespace within). |
| struct Change { |
| /// Functor to sort changes in original source order. |
| class IsBeforeInFile { |
| public: |
| IsBeforeInFile(const SourceManager &SourceMgr) : SourceMgr(SourceMgr) {} |
| bool operator()(const Change &C1, const Change &C2) const; |
| |
| private: |
| const SourceManager &SourceMgr; |
| }; |
| |
| /// Creates a \c Change. |
| /// |
| /// The generated \c Change will replace the characters at |
| /// \p OriginalWhitespaceRange with a concatenation of |
| /// \p PreviousLinePostfix, \p NewlinesBefore line breaks, \p Spaces spaces |
| /// and \p CurrentLinePrefix. |
| /// |
| /// \p StartOfTokenColumn and \p InPPDirective will be used to lay out |
| /// trailing comments and escaped newlines. |
| Change(const FormatToken &Tok, bool CreateReplacement, |
| SourceRange OriginalWhitespaceRange, int Spaces, |
| unsigned StartOfTokenColumn, unsigned NewlinesBefore, |
| StringRef PreviousLinePostfix, StringRef CurrentLinePrefix, |
| bool ContinuesPPDirective, bool IsInsideToken); |
| |
| // The kind of the token whose whitespace this change replaces, or in which |
| // this change inserts whitespace. |
| // FIXME: Currently this is not set correctly for breaks inside comments, as |
| // the \c BreakableToken is still doing its own alignment. |
| const FormatToken *Tok; |
| |
| bool CreateReplacement; |
| // Changes might be in the middle of a token, so we cannot just keep the |
| // FormatToken around to query its information. |
| SourceRange OriginalWhitespaceRange; |
| unsigned StartOfTokenColumn; |
| unsigned NewlinesBefore; |
| std::string PreviousLinePostfix; |
| std::string CurrentLinePrefix; |
| bool ContinuesPPDirective; |
| |
| // The number of spaces in front of the token or broken part of the token. |
| // This will be adapted when aligning tokens. |
| // Can be negative to retain information about the initial relative offset |
| // of the lines in a block comment. This is used when aligning trailing |
| // comments. Uncompensated negative offset is truncated to 0. |
| int Spaces; |
| |
| // If this change is inside of a token but not at the start of the token or |
| // directly after a newline. |
| bool IsInsideToken; |
| |
| // \c IsTrailingComment, \c TokenLength, \c PreviousEndOfTokenColumn and |
| // \c EscapedNewlineColumn will be calculated in |
| // \c calculateLineBreakInformation. |
| bool IsTrailingComment; |
| unsigned TokenLength; |
| unsigned PreviousEndOfTokenColumn; |
| unsigned EscapedNewlineColumn; |
| |
| // These fields are used to retain correct relative line indentation in a |
| // block comment when aligning trailing comments. |
| // |
| // If this Change represents a continuation of a block comment, |
| // \c StartOfBlockComment is pointer to the first Change in the block |
| // comment. \c IndentationOffset is a relative column offset to this |
| // change, so that the correct column can be reconstructed at the end of |
| // the alignment process. |
| const Change *StartOfBlockComment; |
| int IndentationOffset; |
| |
| // A combination of indent level and nesting level, which are used in |
| // tandem to compute lexical scope, for the purposes of deciding |
| // when to stop consecutive alignment runs. |
| std::pair<unsigned, unsigned> indentAndNestingLevel() const { |
| return std::make_pair(Tok->IndentLevel, Tok->NestingLevel); |
| } |
| }; |
| |
| private: |
| /// Calculate \c IsTrailingComment, \c TokenLength for the last tokens |
| /// or token parts in a line and \c PreviousEndOfTokenColumn and |
| /// \c EscapedNewlineColumn for the first tokens or token parts in a line. |
| void calculateLineBreakInformation(); |
| |
| /// \brief Align consecutive C/C++ preprocessor macros over all \c Changes. |
| void alignConsecutiveMacros(); |
| |
| /// Align consecutive assignments over all \c Changes. |
| void alignConsecutiveAssignments(); |
| |
| /// Align consecutive declarations over all \c Changes. |
| void alignConsecutiveDeclarations(); |
| |
| /// Align trailing comments over all \c Changes. |
| void alignTrailingComments(); |
| |
| /// Align trailing comments from change \p Start to change \p End at |
| /// the specified \p Column. |
| void alignTrailingComments(unsigned Start, unsigned End, unsigned Column); |
| |
| /// Align escaped newlines over all \c Changes. |
| void alignEscapedNewlines(); |
| |
| /// Align escaped newlines from change \p Start to change \p End at |
| /// the specified \p Column. |
| void alignEscapedNewlines(unsigned Start, unsigned End, unsigned Column); |
| |
| /// Fill \c Replaces with the replacements for all effective changes. |
| void generateChanges(); |
| |
| /// Stores \p Text as the replacement for the whitespace in \p Range. |
| void storeReplacement(SourceRange Range, StringRef Text); |
| void appendNewlineText(std::string &Text, unsigned Newlines); |
| void appendEscapedNewlineText(std::string &Text, unsigned Newlines, |
| unsigned PreviousEndOfTokenColumn, |
| unsigned EscapedNewlineColumn); |
| void appendIndentText(std::string &Text, unsigned IndentLevel, |
| unsigned Spaces, unsigned WhitespaceStartColumn); |
| |
| SmallVector<Change, 16> Changes; |
| const SourceManager &SourceMgr; |
| tooling::Replacements Replaces; |
| const FormatStyle &Style; |
| bool UseCRLF; |
| }; |
| |
| } // namespace format |
| } // namespace clang |
| |
| #endif |