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Diffstat (limited to 'lib/Format/FormatToken.h')
-rw-r--r-- | lib/Format/FormatToken.h | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/lib/Format/FormatToken.h b/lib/Format/FormatToken.h new file mode 100644 index 0000000..2145ee2 --- /dev/null +++ b/lib/Format/FormatToken.h @@ -0,0 +1,452 @@ +//===--- FormatToken.h - Format C++ code ------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +/// +/// \file +/// \brief This file contains the declaration of the FormatToken, a wrapper +/// around Token with additional information related to formatting. +/// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_FORMAT_FORMAT_TOKEN_H +#define LLVM_CLANG_FORMAT_FORMAT_TOKEN_H + +#include "clang/Basic/OperatorPrecedence.h" +#include "clang/Format/Format.h" +#include "clang/Lex/Lexer.h" +#include "llvm/ADT/OwningPtr.h" + +namespace clang { +namespace format { + +enum TokenType { + TT_ArrayInitializerLSquare, + TT_ArraySubscriptLSquare, + TT_BinaryOperator, + TT_BitFieldColon, + TT_BlockComment, + TT_CastRParen, + TT_ConditionalExpr, + TT_CtorInitializerColon, + TT_CtorInitializerComma, + TT_DesignatedInitializerPeriod, + TT_DictLiteral, + TT_ImplicitStringLiteral, + TT_InlineASMColon, + TT_InheritanceColon, + TT_FunctionTypeLParen, + TT_LambdaLSquare, + TT_LineComment, + TT_ObjCBlockLParen, + TT_ObjCDecl, + TT_ObjCForIn, + TT_ObjCMethodExpr, + TT_ObjCMethodSpecifier, + TT_ObjCProperty, + TT_ObjCSelectorName, + TT_OverloadedOperator, + TT_OverloadedOperatorLParen, + TT_PointerOrReference, + TT_PureVirtualSpecifier, + TT_RangeBasedForLoopColon, + TT_StartOfName, + TT_TemplateCloser, + TT_TemplateOpener, + TT_TrailingReturnArrow, + TT_TrailingUnaryOperator, + TT_UnaryOperator, + TT_Unknown +}; + +// Represents what type of block a set of braces open. +enum BraceBlockKind { + BK_Unknown, + BK_Block, + BK_BracedInit +}; + +// The packing kind of a function's parameters. +enum ParameterPackingKind { + PPK_BinPacked, + PPK_OnePerLine, + PPK_Inconclusive +}; + +enum FormatDecision { + FD_Unformatted, + FD_Continue, + FD_Break +}; + +class TokenRole; +class AnnotatedLine; + +/// \brief A wrapper around a \c Token storing information about the +/// whitespace characters preceeding it. +struct FormatToken { + FormatToken() + : NewlinesBefore(0), HasUnescapedNewline(false), LastNewlineOffset(0), + ColumnWidth(0), LastLineColumnWidth(0), IsMultiline(false), + IsFirst(false), MustBreakBefore(false), IsUnterminatedLiteral(false), + BlockKind(BK_Unknown), Type(TT_Unknown), SpacesRequiredBefore(0), + CanBreakBefore(false), ClosesTemplateDeclaration(false), + ParameterCount(0), PackingKind(PPK_Inconclusive), TotalLength(0), + UnbreakableTailLength(0), BindingStrength(0), SplitPenalty(0), + LongestObjCSelectorName(0), FakeRParens(0), + StartsBinaryExpression(false), EndsBinaryExpression(false), + LastInChainOfCalls(false), PartOfMultiVariableDeclStmt(false), + MatchingParen(NULL), Previous(NULL), Next(NULL), + Decision(FD_Unformatted), Finalized(false) {} + + /// \brief The \c Token. + Token Tok; + + /// \brief The number of newlines immediately before the \c Token. + /// + /// This can be used to determine what the user wrote in the original code + /// and thereby e.g. leave an empty line between two function definitions. + unsigned NewlinesBefore; + + /// \brief Whether there is at least one unescaped newline before the \c + /// Token. + bool HasUnescapedNewline; + + /// \brief The range of the whitespace immediately preceeding the \c Token. + SourceRange WhitespaceRange; + + /// \brief The offset just past the last '\n' in this token's leading + /// whitespace (relative to \c WhiteSpaceStart). 0 if there is no '\n'. + unsigned LastNewlineOffset; + + /// \brief The width of the non-whitespace parts of the token (or its first + /// line for multi-line tokens) in columns. + /// We need this to correctly measure number of columns a token spans. + unsigned ColumnWidth; + + /// \brief Contains the width in columns of the last line of a multi-line + /// token. + unsigned LastLineColumnWidth; + + /// \brief Whether the token text contains newlines (escaped or not). + bool IsMultiline; + + /// \brief Indicates that this is the first token. + bool IsFirst; + + /// \brief Whether there must be a line break before this token. + /// + /// This happens for example when a preprocessor directive ended directly + /// before the token. + bool MustBreakBefore; + + /// \brief Returns actual token start location without leading escaped + /// newlines and whitespace. + /// + /// This can be different to Tok.getLocation(), which includes leading escaped + /// newlines. + SourceLocation getStartOfNonWhitespace() const { + return WhitespaceRange.getEnd(); + } + + /// \brief The raw text of the token. + /// + /// Contains the raw token text without leading whitespace and without leading + /// escaped newlines. + StringRef TokenText; + + /// \brief Set to \c true if this token is an unterminated literal. + bool IsUnterminatedLiteral; + + /// \brief Contains the kind of block if this token is a brace. + BraceBlockKind BlockKind; + + TokenType Type; + + /// \brief The number of spaces that should be inserted before this token. + unsigned SpacesRequiredBefore; + + /// \brief \c true if it is allowed to break before this token. + bool CanBreakBefore; + + bool ClosesTemplateDeclaration; + + /// \brief Number of parameters, if this is "(", "[" or "<". + /// + /// This is initialized to 1 as we don't need to distinguish functions with + /// 0 parameters from functions with 1 parameter. Thus, we can simply count + /// the number of commas. + unsigned ParameterCount; + + /// \brief A token can have a special role that can carry extra information + /// about the token's formatting. + llvm::OwningPtr<TokenRole> Role; + + /// \brief If this is an opening parenthesis, how are the parameters packed? + ParameterPackingKind PackingKind; + + /// \brief The total length of the unwrapped line up to and including this + /// token. + unsigned TotalLength; + + /// \brief The original 0-based column of this token, including expanded tabs. + /// The configured TabWidth is used as tab width. + unsigned OriginalColumn; + + /// \brief The length of following tokens until the next natural split point, + /// or the next token that can be broken. + unsigned UnbreakableTailLength; + + // FIXME: Come up with a 'cleaner' concept. + /// \brief The binding strength of a token. This is a combined value of + /// operator precedence, parenthesis nesting, etc. + unsigned BindingStrength; + + /// \brief Penalty for inserting a line break before this token. + unsigned SplitPenalty; + + /// \brief If this is the first ObjC selector name in an ObjC method + /// definition or call, this contains the length of the longest name. + unsigned LongestObjCSelectorName; + + /// \brief Stores the number of required fake parentheses and the + /// corresponding operator precedence. + /// + /// If multiple fake parentheses start at a token, this vector stores them in + /// reverse order, i.e. inner fake parenthesis first. + SmallVector<prec::Level, 4> FakeLParens; + /// \brief Insert this many fake ) after this token for correct indentation. + unsigned FakeRParens; + + /// \brief \c true if this token starts a binary expression, i.e. has at least + /// one fake l_paren with a precedence greater than prec::Unknown. + bool StartsBinaryExpression; + /// \brief \c true if this token ends a binary expression. + bool EndsBinaryExpression; + + /// \brief Is this the last "." or "->" in a builder-type call? + bool LastInChainOfCalls; + + /// \brief Is this token part of a \c DeclStmt defining multiple variables? + /// + /// Only set if \c Type == \c TT_StartOfName. + bool PartOfMultiVariableDeclStmt; + + bool is(tok::TokenKind Kind) const { return Tok.is(Kind); } + + bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const { + return is(K1) || is(K2); + } + + bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, tok::TokenKind K3) const { + return is(K1) || is(K2) || is(K3); + } + + bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, tok::TokenKind K3, + tok::TokenKind K4, tok::TokenKind K5 = tok::NUM_TOKENS, + tok::TokenKind K6 = tok::NUM_TOKENS, + tok::TokenKind K7 = tok::NUM_TOKENS, + tok::TokenKind K8 = tok::NUM_TOKENS, + tok::TokenKind K9 = tok::NUM_TOKENS, + tok::TokenKind K10 = tok::NUM_TOKENS, + tok::TokenKind K11 = tok::NUM_TOKENS, + tok::TokenKind K12 = tok::NUM_TOKENS) const { + return is(K1) || is(K2) || is(K3) || is(K4) || is(K5) || is(K6) || is(K7) || + is(K8) || is(K9) || is(K10) || is(K11) || is(K12); + } + + bool isNot(tok::TokenKind Kind) const { return Tok.isNot(Kind); } + + bool isObjCAtKeyword(tok::ObjCKeywordKind Kind) const { + return Tok.isObjCAtKeyword(Kind); + } + + bool isAccessSpecifier(bool ColonRequired = true) const { + return isOneOf(tok::kw_public, tok::kw_protected, tok::kw_private) && + (!ColonRequired || (Next && Next->is(tok::colon))); + } + + bool isObjCAccessSpecifier() const { + return is(tok::at) && Next && (Next->isObjCAtKeyword(tok::objc_public) || + Next->isObjCAtKeyword(tok::objc_protected) || + Next->isObjCAtKeyword(tok::objc_package) || + Next->isObjCAtKeyword(tok::objc_private)); + } + + /// \brief Returns whether \p Tok is ([{ or a template opening <. + bool opensScope() const { + return isOneOf(tok::l_paren, tok::l_brace, tok::l_square) || + Type == TT_TemplateOpener; + } + /// \brief Returns whether \p Tok is )]} or a template closing >. + bool closesScope() const { + return isOneOf(tok::r_paren, tok::r_brace, tok::r_square) || + Type == TT_TemplateCloser; + } + + /// \brief Returns \c true if this is a "." or "->" accessing a member. + bool isMemberAccess() const { + return isOneOf(tok::arrow, tok::period) && + Type != TT_DesignatedInitializerPeriod; + } + + bool isUnaryOperator() const { + switch (Tok.getKind()) { + case tok::plus: + case tok::plusplus: + case tok::minus: + case tok::minusminus: + case tok::exclaim: + case tok::tilde: + case tok::kw_sizeof: + case tok::kw_alignof: + return true; + default: + return false; + } + } + + bool isBinaryOperator() const { + // Comma is a binary operator, but does not behave as such wrt. formatting. + return getPrecedence() > prec::Comma; + } + + bool isTrailingComment() const { + return is(tok::comment) && (!Next || Next->NewlinesBefore > 0); + } + + prec::Level getPrecedence() const { + return getBinOpPrecedence(Tok.getKind(), true, true); + } + + /// \brief Returns the previous token ignoring comments. + FormatToken *getPreviousNonComment() const { + FormatToken *Tok = Previous; + while (Tok != NULL && Tok->is(tok::comment)) + Tok = Tok->Previous; + return Tok; + } + + /// \brief Returns the next token ignoring comments. + const FormatToken *getNextNonComment() const { + const FormatToken *Tok = Next; + while (Tok != NULL && Tok->is(tok::comment)) + Tok = Tok->Next; + return Tok; + } + + /// \brief Returns \c true if this tokens starts a block-type list, i.e. a + /// list that should be indented with a block indent. + bool opensBlockTypeList(const FormatStyle &Style) const { + return Type == TT_ArrayInitializerLSquare || + (is(tok::l_brace) && + (BlockKind == BK_Block || Type == TT_DictLiteral || + !Style.Cpp11BracedListStyle)); + } + + /// \brief Same as opensBlockTypeList, but for the closing token. + bool closesBlockTypeList(const FormatStyle &Style) const { + return MatchingParen && MatchingParen->opensBlockTypeList(Style); + } + + FormatToken *MatchingParen; + + FormatToken *Previous; + FormatToken *Next; + + SmallVector<AnnotatedLine *, 1> Children; + + /// \brief Stores the formatting decision for the token once it was made. + FormatDecision Decision; + + /// \brief If \c true, this token has been fully formatted (indented and + /// potentially re-formatted inside), and we do not allow further formatting + /// changes. + bool Finalized; + +private: + // Disallow copying. + FormatToken(const FormatToken &) LLVM_DELETED_FUNCTION; + void operator=(const FormatToken &) LLVM_DELETED_FUNCTION; +}; + +class ContinuationIndenter; +struct LineState; + +class TokenRole { +public: + TokenRole(const FormatStyle &Style) : Style(Style) {} + virtual ~TokenRole(); + + /// \brief After the \c TokenAnnotator has finished annotating all the tokens, + /// this function precomputes required information for formatting. + virtual void precomputeFormattingInfos(const FormatToken *Token); + + /// \brief Apply the special formatting that the given role demands. + /// + /// Continues formatting from \p State leaving indentation to \p Indenter and + /// returns the total penalty that this formatting incurs. + virtual unsigned format(LineState &State, ContinuationIndenter *Indenter, + bool DryRun) { + return 0; + } + + /// \brief Notifies the \c Role that a comma was found. + virtual void CommaFound(const FormatToken *Token) {} + +protected: + const FormatStyle &Style; +}; + +class CommaSeparatedList : public TokenRole { +public: + CommaSeparatedList(const FormatStyle &Style) : TokenRole(Style) {} + + virtual void precomputeFormattingInfos(const FormatToken *Token); + + virtual unsigned format(LineState &State, ContinuationIndenter *Indenter, + bool DryRun); + + /// \brief Adds \p Token as the next comma to the \c CommaSeparated list. + virtual void CommaFound(const FormatToken *Token) { Commas.push_back(Token); } + +private: + /// \brief A struct that holds information on how to format a given list with + /// a specific number of columns. + struct ColumnFormat { + /// \brief The number of columns to use. + unsigned Columns; + + /// \brief The total width in characters. + unsigned TotalWidth; + + /// \brief The number of lines required for this format. + unsigned LineCount; + + /// \brief The size of each column in characters. + SmallVector<unsigned, 8> ColumnSizes; + }; + + /// \brief Calculate which \c ColumnFormat fits best into + /// \p RemainingCharacters. + const ColumnFormat *getColumnFormat(unsigned RemainingCharacters) const; + + /// \brief The ordered \c FormatTokens making up the commas of this list. + SmallVector<const FormatToken *, 8> Commas; + + /// \brief The length of each of the list's items in characters including the + /// trailing comma. + SmallVector<unsigned, 8> ItemLengths; + + /// \brief Precomputed formats that can be used for this list. + SmallVector<ColumnFormat, 4> Formats; +}; + +} // namespace format +} // namespace clang + +#endif // LLVM_CLANG_FORMAT_FORMAT_TOKEN_H |