//===--- TokenAnnotator.cpp - Format C++ code -----------------------------===//
//
// 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 implements a token annotator, i.e. creates
/// \c AnnotatedTokens out of \c FormatTokens with required extra information.
///
//===----------------------------------------------------------------------===//
#include "TokenAnnotator.h"
#include "clang/Basic/SourceManager.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "format-token-annotator"
namespace clang {
namespace format {
namespace {
/// \brief A parser that gathers additional information about tokens.
///
/// The \c TokenAnnotator tries to match parenthesis and square brakets and
/// store a parenthesis levels. It also tries to resolve matching "<" and ">"
/// into template parameter lists.
class AnnotatingParser {
public:
AnnotatingParser(const FormatStyle &Style, AnnotatedLine &Line,
IdentifierInfo &Ident_in)
: Style(Style), Line(Line), CurrentToken(Line.First),
KeywordVirtualFound(false), AutoFound(false), Ident_in(Ident_in) {
Contexts.push_back(Context(tok::unknown, 1, /*IsExpression=*/false));
resetTokenMetadata(CurrentToken);
}
private:
bool parseAngle() {
if (!CurrentToken)
return false;
ScopedContextCreator ContextCreator(*this, tok::less, 10);
FormatToken *Left = CurrentToken->Previous;
Contexts.back().IsExpression = false;
// If there's a template keyword before the opening angle bracket, this is a
// template parameter, not an argument.
Contexts.back().InTemplateArgument =
Left->Previous && Left->Previous->Tok.isNot(tok::kw_template);
while (CurrentToken) {
if (CurrentToken->is(tok::greater)) {
Left->MatchingParen = CurrentToken;
CurrentToken->MatchingParen = Left;
CurrentToken->Type = TT_TemplateCloser;
next();
return true;
}
if (CurrentToken->isOneOf(tok::r_paren, tok::r_square, tok::r_brace,
tok::question, tok::colon))
return false;
// If a && or || is found and interpreted as a binary operator, this set
// of angles is likely part of something like "a < b && c > d". If the
// angles are inside an expression, the ||/&& might also be a binary
// operator that was misinterpreted because we are parsing template
// parameters.
// FIXME: This is getting out of hand, write a decent parser.
if (CurrentToken->Previous->isOneOf(tok::pipepipe, tok::ampamp) &&
((CurrentToken->Previous->Type == TT_BinaryOperator &&
// Toplevel bool expressions do not make lots of sense;
// If we're on the top level, it contains only the base context and
// the context for the current opening angle bracket.
Contexts.size() > 2) ||
Contexts[Contexts.size() - 2].IsExpression) &&
Line.First->isNot(tok::kw_template))
return false;
updateParameterCount(Left, CurrentToken);
if (!consumeToken())
return false;
}
return false;
}
bool parseParens(bool LookForDecls = false) {
if (!CurrentToken)
return false;
ScopedContextCreator ContextCreator(*this, tok::l_paren, 1);
// FIXME: This is a bit of a hack. Do better.
Contexts.back().ColonIsForRangeExpr =
Contexts.size() == 2 && Contexts[0].ColonIsForRangeExpr;
bool StartsObjCMethodExpr = false;
FormatToken *Left = CurrentToken->Previous;
if (CurrentToken->is(tok::caret)) {
// (^ can start a block type.
Left->Type = TT_ObjCBlockLParen;
} else if (FormatToken *MaybeSel = Left->Previous) {
// @selector( starts a selector.
if (MaybeSel->isObjCAtKeyword(tok::objc_selector) && MaybeSel->Previous &&
MaybeSel->Previous->is(tok::at)) {
StartsObjCMethodExpr = true;
}
}
if (Left->Previous &&
(Left->Previous->isOneOf(tok::kw_static_assert, tok::kw_if,
tok::kw_while, tok::l_paren, tok::comma) ||
Left->Previous->Type == TT_BinaryOperator)) {
// static_assert, if and while usually contain expressions.
Contexts.back().IsExpression = true;
} else if (Line.InPPDirective &&
(!Left->Previous ||
(Left->Previous->isNot(tok::identifier) &&
Left->Previous->Type != TT_OverloadedOperator))) {
Contexts.back().IsExpression = true;
} else if (Left->Previous && Left->Previous->is(tok::r_square) &&
Left->Previous->MatchingParen &&
Left->Previous->MatchingParen->Type == TT_LambdaLSquare) {
// This is a parameter list of a lambda expression.
Contexts.back().IsExpression = false;
} else if (Contexts[Contexts.size() - 2].CaretFound) {
// This is the parameter list of an ObjC block.
Contexts.back().IsExpression = false;
} else if (Left->Previous && Left->Previous->is(tok::kw___attribute)) {
Left->Type = TT_AttributeParen;
} else if (Left->Previous && Left->Previous->IsForEachMacro) {
// The first argument to a foreach macro is a declaration.
Contexts.back().IsForEachMacro = true;
Contexts.back().IsExpression = false;
}
if (StartsObjCMethodExpr) {
Contexts.back().ColonIsObjCMethodExpr = true;
Left->Type = TT_ObjCMethodExpr;
}
bool MightBeFunctionType = CurrentToken->is(tok::star);
bool HasMultipleLines = false;
bool HasMultipleParametersOnALine = false;
while (CurrentToken) {
// LookForDecls is set when "if (" has been seen. Check for
// 'identifier' '*' 'identifier' followed by not '=' -- this
// '*' has to be a binary operator but determineStarAmpUsage() will
// categorize it as an unary operator, so set the right type here.
if (LookForDecls && CurrentToken->Next) {
FormatToken *Prev = CurrentToken->getPreviousNonComment();
if (Prev) {
FormatToken *PrevPrev = Prev->getPreviousNonComment();
FormatToken *Next = CurrentToken->Next;
if (PrevPrev && PrevPrev->is(tok::identifier) &&
Prev->isOneOf(tok::star, tok::amp, tok::ampamp) &&
CurrentToken->is(tok::identifier) && Next->isNot(tok::equal)) {
Prev->Type = TT_BinaryOperator;
LookForDecls = false;
}
}
}
if (CurrentToken->Previous->Type == TT_PointerOrReference &&
CurrentToken->Previous->Previous->isOneOf(tok::l_paren,
tok::coloncolon))
MightBeFunctionType = true;
if (CurrentToken->Previous->Type == TT_BinaryOperator)
Contexts.back().IsExpression = true;
if (CurrentToken->is(tok::r_paren)) {
if (MightBeFunctionType && CurrentToken->Next &&
(CurrentToken->Next->is(tok::l_paren) ||
(CurrentToken->Next->is(tok::l_square) &&
!Contexts.back().IsExpression)))
Left->Type = TT_FunctionTypeLParen;
Left->MatchingParen = CurrentToken;
CurrentToken->MatchingParen = Left;
if (StartsObjCMethodExpr) {
CurrentToken->Type = TT_ObjCMethodExpr;
if (Contexts.back().FirstObjCSelectorName) {
Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
Contexts.back().LongestObjCSelectorName;
}
}
if (Left->Type == TT_AttributeParen)
CurrentToken->Type = TT_AttributeParen;
if (!HasMultipleLines)
Left->PackingKind = PPK_Inconclusive;
else if (HasMultipleParametersOnALine)
Left->PackingKind = PPK_BinPacked;
else
Left->PackingKind = PPK_OnePerLine;
next();
return true;
}
if (CurrentToken->isOneOf(tok::r_square, tok::r_brace))
return false;
else if (CurrentToken->is(tok::l_brace))
Left->Type = TT_Unknown; // Not TT_ObjCBlockLParen
if (CurrentToken->is(tok::comma) && CurrentToken->Next &&
!CurrentToken->Next->HasUnescapedNewline &&
!CurrentToken->Next->isTrailingComment())
HasMultipleParametersOnALine = true;
if (CurrentToken->isOneOf(tok::kw_const, tok::kw_auto) ||
CurrentToken->isSimpleTypeSpecifier())
Contexts.back().IsExpression = false;
FormatToken *Tok = CurrentToken;
if (!consumeToken())
return false;
updateParameterCount(Left, Tok);
if (CurrentToken && CurrentToken->HasUnescapedNewline)
HasMultipleLines = true;
}
return false;
}
bool parseSquare() {
if (!CurrentToken)
return false;
// A '[' could be an index subscript (after an identifier or after
// ')' or ']'), it could be the start of an Objective-C method
// expression, or it could the the start of an Objective-C array literal.
FormatToken *Left = CurrentToken->Previous;
FormatToken *Parent = Left->getPreviousNonComment();
bool StartsObjCMethodExpr =
Contexts.back().CanBeExpression && Left->Type != TT_LambdaLSquare &&
CurrentToken->isNot(tok::l_brace) &&
(!Parent || Parent->isOneOf(tok::colon, tok::l_square, tok::l_paren,
tok::kw_return, tok::kw_throw) ||
Parent->isUnaryOperator() || Parent->Type == TT_ObjCForIn ||
Parent->Type == TT_CastRParen ||
getBinOpPrecedence(Parent->Tok.getKind(), true, true) > prec::Unknown);
ScopedContextCreator ContextCreator(*this, tok::l_square, 10);
Contexts.back().IsExpression = true;
bool ColonFound = false;
if (StartsObjCMethodExpr) {
Contexts.back().ColonIsObjCMethodExpr = true;
Left->Type = TT_ObjCMethodExpr;
} else if (Parent && Parent->is(tok::at)) {
Left->Type = TT_ArrayInitializerLSquare;
} else if (Left->Type == TT_Unknown) {
Left->Type = TT_ArraySubscriptLSquare;
}
while (CurrentToken) {
if (CurrentToken->is(tok::r_square)) {
if (CurrentToken->Next && CurrentToken->Next->is(tok::l_paren) &&
Left->Type == TT_ObjCMethodExpr) {
// An ObjC method call is rarely followed by an open parenthesis.
// FIXME: Do we incorrectly label ":" with this?
StartsObjCMethodExpr = false;
Left->Type = TT_Unknown;
}
if (StartsObjCMethodExpr && CurrentToken->Previous != Left) {
CurrentToken->Type = TT_ObjCMethodExpr;
// determineStarAmpUsage() thinks that '*' '[' is allocating an
// array of pointers, but if '[' starts a selector then '*' is a
// binary operator.
if (Parent && Parent->Type == TT_PointerOrReference)
Parent->Type = TT_BinaryOperator;
}
Left->MatchingParen = CurrentToken;
CurrentToken->MatchingParen = Left;
if (Contexts.back().FirstObjCSelectorName) {
Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
Contexts.back().LongestObjCSelectorName;
if (Left->BlockParameterCount > 1)
Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName = 0;
}
next();
return true;
}
if (CurrentToken->isOneOf(tok::r_paren, tok::r_brace))
return false;
if (CurrentToken->is(tok::colon))
ColonFound = true;
if (CurrentToken->is(tok::comma) &&
Style.Language != FormatStyle::LK_Proto &&
(Left->Type == TT_ArraySubscriptLSquare ||
(Left->Type == TT_ObjCMethodExpr && !ColonFound)))
Left->Type = TT_ArrayInitializerLSquare;
FormatToken* Tok = CurrentToken;
if (!consumeToken())
return false;
updateParameterCount(Left, Tok);
}
return false;
}
bool parseBrace() {
if (CurrentToken) {
FormatToken *Left = CurrentToken->Previous;
if (Contexts.back().CaretFound)
Left->Type = TT_ObjCBlockLBrace;
Contexts.back().CaretFound = false;
ScopedContextCreator ContextCreator(*this, tok::l_brace, 1);
Contexts.back().ColonIsDictLiteral = true;
if (Left->BlockKind == BK_BracedInit)
Contexts.back().IsExpression = true;
while (CurrentToken) {
if (CurrentToken->is(tok::r_brace)) {
Left->MatchingParen = CurrentToken;
CurrentToken->MatchingParen = Left;
next();
return true;
}
if (CurrentToken->isOneOf(tok::r_paren, tok::r_square))
return false;
updateParameterCount(Left, CurrentToken);
if (CurrentToken->is(tok::colon) &&
Style.Language != FormatStyle::LK_Proto) {
if (CurrentToken->getPreviousNonComment()->is(tok::identifier))
CurrentToken->getPreviousNonComment()->Type = TT_SelectorName;
Left->Type = TT_DictLiteral;
}
if (!consumeToken())
return false;
}
}
return true;
}
void updateParameterCount(FormatToken *Left, FormatToken *Current) {
if (Current->Type == TT_LambdaLSquare ||
(Current->is(tok::caret) && Current->Type == TT_UnaryOperator) ||
(Style.Language == FormatStyle::LK_JavaScript &&
Current->TokenText == "function")) {
++Left->BlockParameterCount;
}
if (Current->is(tok::comma)) {
++Left->ParameterCount;
if (!Left->Role)
Left->Role.reset(new CommaSeparatedList(Style));
Left->Role->CommaFound(Current);
} else if (Left->ParameterCount == 0 && Current->isNot(tok::comment)) {
Left->ParameterCount = 1;
}
}
bool parseConditional() {
while (CurrentToken) {
if (CurrentToken->is(tok::colon)) {
CurrentToken->Type = TT_ConditionalExpr;
next();
return true;
}
if (!consumeToken())
return false;
}
return false;
}
bool parseTemplateDeclaration() {
if (CurrentToken && CurrentToken->is(tok::less)) {
CurrentToken->Type = TT_TemplateOpener;
next();
if (!parseAngle())
return false;
if (CurrentToken)
CurrentToken->Previous->ClosesTemplateDeclaration = true;
return true;
}
return false;
}
bool consumeToken() {
FormatToken *Tok = CurrentToken;
next();
switch (Tok->Tok.getKind()) {
case tok::plus:
case tok::minus:
if (!Tok->Previous && Line.MustBeDeclaration)
Tok->Type = TT_ObjCMethodSpecifier;
break;
case tok::colon:
if (!Tok->Previous)
return false;
// Colons from ?: are handled in parseConditional().
if (Tok->Previous->is(tok::r_paren) && Contexts.size() == 1 &&
Line.First->isNot(tok::kw_case)) {
Tok->Type = TT_CtorInitializerColon;
} else if (Contexts.back().ColonIsDictLiteral) {
Tok->Type = TT_DictLiteral;
} else if (Contexts.back().ColonIsObjCMethodExpr ||
Line.First->Type == TT_ObjCMethodSpecifier) {
Tok->Type = TT_ObjCMethodExpr;
Tok->Previous->Type = TT_SelectorName;
if (Tok->Previous->ColumnWidth >
Contexts.back().LongestObjCSelectorName) {
Contexts.back().LongestObjCSelectorName = Tok->Previous->ColumnWidth;
}
if (!Contexts.back().FirstObjCSelectorName)
Contexts.back().FirstObjCSelectorName = Tok->Previous;
} else if (Contexts.back().ColonIsForRangeExpr) {
Tok->Type = TT_RangeBasedForLoopColon;
} else if (CurrentToken && CurrentToken->is(tok::numeric_constant)) {
Tok->Type = TT_BitFieldColon;
} else if (Contexts.size() == 1 &&
!Line.First->isOneOf(tok::kw_enum, tok::kw_case)) {
Tok->Type = TT_InheritanceColon;
} else if (Contexts.back().ContextKind == tok::l_paren) {
Tok->Type = TT_InlineASMColon;
}
break;
case tok::kw_if:
case tok::kw_while:
if (CurrentToken && CurrentToken->is(tok::l_paren)) {
next();
if (!parseParens(/*LookForDecls=*/true))
return false;
}
break;
case tok::kw_for:
Contexts.back().ColonIsForRangeExpr = true;
next();
if (!parseParens())
return false;
break;
case tok::l_paren:
if (!parseParens())
return false;
if (Line.MustBeDeclaration && Contexts.size() == 1 &&
!Contexts.back().IsExpression &&
Line.First->Type != TT_ObjCProperty &&
(!Tok->Previous || Tok->Previous->isNot(tok::kw_decltype)))
Line.MightBeFunctionDecl = true;
break;
case tok::l_square:
if (!parseSquare())
return false;
break;
case tok::l_brace:
if (!parseBrace())
return false;
break;
case tok::less:
if (Tok->Previous && !Tok->Previous->Tok.isLiteral() && parseAngle())
Tok->Type = TT_TemplateOpener;
else {
Tok->Type = TT_BinaryOperator;
CurrentToken = Tok;
next();
}
break;
case tok::r_paren:
case tok::r_square:
return false;
case tok::r_brace:
// Lines can start with '}'.
if (Tok->Previous)
return false;
break;
case tok::greater:
Tok->Type = TT_BinaryOperator;
break;
case tok::kw_operator:
while (CurrentToken &&
!CurrentToken->isOneOf(tok::l_paren, tok::semi, tok::r_paren)) {
if (CurrentToken->isOneOf(tok::star, tok::amp))
CurrentToken->Type = TT_PointerOrReference;
consumeToken();
if (CurrentToken && CurrentToken->Previous->Type == TT_BinaryOperator)
CurrentToken->Previous->Type = TT_OverloadedOperator;
}
if (CurrentToken) {
CurrentToken->Type = TT_OverloadedOperatorLParen;
if (CurrentToken->Previous->Type == TT_BinaryOperator)
CurrentToken->Previous->Type = TT_OverloadedOperator;
}
break;
case tok::question:
parseConditional();
break;
case tok::kw_template:
parseTemplateDeclaration();
break;
case tok::identifier:
if (Line.First->is(tok::kw_for) &&
Tok->Tok.getIdentifierInfo() == &Ident_in)
Tok->Type = TT_ObjCForIn;
break;
case tok::comma:
if (Contexts.back().FirstStartOfName)
Contexts.back().FirstStartOfName->PartOfMultiVariableDeclStmt = true;
if (Contexts.back().InCtorInitializer)
Tok->Type = TT_CtorInitializerComma;
if (Contexts.back().IsForEachMacro)
Contexts.back().IsExpression = true;
break;
default:
break;
}
return true;
}
void parseIncludeDirective() {
next();
if (CurrentToken && CurrentToken->is(tok::less)) {
next();
while (CurrentToken) {
if (CurrentToken->isNot(tok::comment) || CurrentToken->Next)
CurrentToken->Type = TT_ImplicitStringLiteral;
next();
}
} else {
while (CurrentToken) {
if (CurrentToken->is(tok::string_literal))
// Mark these string literals as "implicit" literals, too, so that
// they are not split or line-wrapped.
CurrentToken->Type = TT_ImplicitStringLiteral;
next();
}
}
}
void parseWarningOrError() {
next();
// We still want to format the whitespace left of the first token of the
// warning or error.
next();
while (CurrentToken) {
CurrentToken->Type = TT_ImplicitStringLiteral;
next();
}
}
void parsePragma() {
next(); // Consume "pragma".
if (CurrentToken && CurrentToken->TokenText == "mark") {
next(); // Consume "mark".
next(); // Consume first token (so we fix leading whitespace).
while (CurrentToken) {
CurrentToken->Type = TT_ImplicitStringLiteral;
next();
}
}
}
void parsePreprocessorDirective() {
next();
if (!CurrentToken)
return;
if (CurrentToken->Tok.is(tok::numeric_constant)) {
CurrentToken->SpacesRequiredBefore = 1;
return;
}
// Hashes in the middle of a line can lead to any strange token
// sequence.
if (!CurrentToken->Tok.getIdentifierInfo())
return;
switch (CurrentToken->Tok.getIdentifierInfo()->getPPKeywordID()) {
case tok::pp_include:
case tok::pp_import:
parseIncludeDirective();
break;
case tok::pp_error:
case tok::pp_warning:
parseWarningOrError();
break;
case tok::pp_pragma:
parsePragma();
break;
case tok::pp_if:
case tok::pp_elif:
Contexts.back().IsExpression = true;
parseLine();
break;
default:
break;
}
while (CurrentToken)
next();
}
public:
LineType parseLine() {
if (CurrentToken->is(tok::hash)) {
parsePreprocessorDirective();
return LT_PreprocessorDirective;
}
// Directly allow to 'import <string-literal>' to support protocol buffer
// definitions (code.google.com/p/protobuf) or missing "#" (either way we
// should not break the line).
IdentifierInfo *Info = CurrentToken->Tok.getIdentifierInfo();
if (Info && Info->getPPKeywordID() == tok::pp_import &&
CurrentToken->Next && CurrentToken->Next->is(tok::string_literal))
parseIncludeDirective();
while (CurrentToken) {
if (CurrentToken->is(tok::kw_virtual))
KeywordVirtualFound = true;
if (!consumeToken())
return LT_Invalid;
}
if (KeywordVirtualFound)
return LT_VirtualFunctionDecl;
if (Line.First->Type == TT_ObjCMethodSpecifier) {
if (Contexts.back().FirstObjCSelectorName)
Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
Contexts.back().LongestObjCSelectorName;
return LT_ObjCMethodDecl;
}
return LT_Other;
}
private:
void resetTokenMetadata(FormatToken *Token) {
if (!Token)
return;
// Reset token type in case we have already looked at it and then
// recovered from an error (e.g. failure to find the matching >).
if (CurrentToken->Type != TT_LambdaLSquare &&
CurrentToken->Type != TT_FunctionLBrace &&
CurrentToken->Type != TT_ImplicitStringLiteral &&
CurrentToken->Type != TT_RegexLiteral &&
CurrentToken->Type != TT_TrailingReturnArrow)
CurrentToken->Type = TT_Unknown;
if (CurrentToken->Role)
CurrentToken->Role.reset(nullptr);
CurrentToken->FakeLParens.clear();
CurrentToken->FakeRParens = 0;
}
void next() {
if (CurrentToken) {
determineTokenType(*CurrentToken);
CurrentToken->BindingStrength = Contexts.back().BindingStrength;
CurrentToken->NestingLevel = Contexts.size() - 1;
CurrentToken = CurrentToken->Next;
}
resetTokenMetadata(CurrentToken);
}
/// \brief A struct to hold information valid in a specific context, e.g.
/// a pair of parenthesis.
struct Context {
Context(tok::TokenKind ContextKind, unsigned BindingStrength,
bool IsExpression)
: ContextKind(ContextKind), BindingStrength(BindingStrength),
LongestObjCSelectorName(0), ColonIsForRangeExpr(false),
ColonIsDictLiteral(false), ColonIsObjCMethodExpr(false),
FirstObjCSelectorName(nullptr), FirstStartOfName(nullptr),
IsExpression(IsExpression), CanBeExpression(true),
InTemplateArgument(false), InCtorInitializer(false),
CaretFound(false), IsForEachMacro(false) {}
tok::TokenKind ContextKind;
unsigned BindingStrength;
unsigned LongestObjCSelectorName;
bool ColonIsForRangeExpr;
bool ColonIsDictLiteral;
bool ColonIsObjCMethodExpr;
FormatToken *FirstObjCSelectorName;
FormatToken *FirstStartOfName;
bool IsExpression;
bool CanBeExpression;
bool InTemplateArgument;
bool InCtorInitializer;
bool CaretFound;
bool IsForEachMacro;
};
/// \brief Puts a new \c Context onto the stack \c Contexts for the lifetime
/// of each instance.
struct ScopedContextCreator {
AnnotatingParser &P;
ScopedContextCreator(AnnotatingParser &P, tok::TokenKind ContextKind,
unsigned Increase)
: P(P) {
P.Contexts.push_back(Context(ContextKind,
P.Contexts.back().BindingStrength + Increase,
P.Contexts.back().IsExpression));
}
~ScopedContextCreator() { P.Contexts.pop_back(); }
};
void determineTokenType(FormatToken &Current) {
if (Current.getPrecedence() == prec::Assignment &&
!Line.First->isOneOf(tok::kw_template, tok::kw_using) &&
(!Current.Previous || Current.Previous->isNot(tok::kw_operator))) {
Contexts.back().IsExpression = true;
for (FormatToken *Previous = Current.Previous;
Previous && !Previous->isOneOf(tok::comma, tok::semi);
Previous = Previous->Previous) {
if (Previous->isOneOf(tok::r_square, tok::r_paren))
Previous = Previous->MatchingParen;
if (Previous->Type == TT_BinaryOperator &&
Previous->isOneOf(tok::star, tok::amp)) {
Previous->Type = TT_PointerOrReference;
}
}
} else if (Current.isOneOf(tok::kw_return, tok::kw_throw)) {
Contexts.back().IsExpression = true;
} else if (Current.is(tok::l_paren) && !Line.MustBeDeclaration &&
!Line.InPPDirective &&
(!Current.Previous ||
Current.Previous->isNot(tok::kw_decltype))) {
bool ParametersOfFunctionType =
Current.Previous && Current.Previous->is(tok::r_paren) &&
Current.Previous->MatchingParen &&
Current.Previous->MatchingParen->Type == TT_FunctionTypeLParen;
bool IsForOrCatch = Current.Previous &&
Current.Previous->isOneOf(tok::kw_for, tok::kw_catch);
Contexts.back().IsExpression = !ParametersOfFunctionType && !IsForOrCatch;
} else if (Current.isOneOf(tok::r_paren, tok::greater, tok::comma)) {
for (FormatToken *Previous = Current.Previous;
Previous && Previous->isOneOf(tok::star, tok::amp);
Previous = Previous->Previous)
Previous->Type = TT_PointerOrReference;
} else if (Current.Previous &&
Current.Previous->Type == TT_CtorInitializerColon) {
Contexts.back().IsExpression = true;
Contexts.back().InCtorInitializer = true;
} else if (Current.is(tok::kw_new)) {
Contexts.back().CanBeExpression = false;
} else if (Current.is(tok::semi) || Current.is(tok::exclaim)) {
// This should be the condition or increment in a for-loop.
Contexts.back().IsExpression = true;
}
if (Current.Type == TT_Unknown) {
// Line.MightBeFunctionDecl can only be true after the parentheses of a
// function declaration have been found. In this case, 'Current' is a
// trailing token of this declaration and thus cannot be a name.
if (isStartOfName(Current) && !Line.MightBeFunctionDecl) {
Contexts.back().FirstStartOfName = &Current;
Current.Type = TT_StartOfName;
} else if (Current.is(tok::kw_auto)) {
AutoFound = true;
} else if (Current.is(tok::arrow) && AutoFound &&
Line.MustBeDeclaration) {
Current.Type = TT_TrailingReturnArrow;
} else if (Current.isOneOf(tok::star, tok::amp, tok::ampamp)) {
Current.Type =
determineStarAmpUsage(Current, Contexts.back().CanBeExpression &&
Contexts.back().IsExpression,
Contexts.back().InTemplateArgument);
} else if (Current.isOneOf(tok::minus, tok::plus, tok::caret)) {
Current.Type = determinePlusMinusCaretUsage(Current);
if (Current.Type == TT_UnaryOperator && Current.is(tok::caret))
Contexts.back().CaretFound = true;
} else if (Current.isOneOf(tok::minusminus, tok::plusplus)) {
Current.Type = determineIncrementUsage(Current);
} else if (Current.is(tok::exclaim)) {
Current.Type = TT_UnaryOperator;
} else if (Current.is(tok::question)) {
Current.Type = TT_ConditionalExpr;
} else if (Current.isBinaryOperator() &&
(!Current.Previous ||
Current.Previous->isNot(tok::l_square))) {
Current.Type = TT_BinaryOperator;
} else if (Current.is(tok::comment)) {
if (Current.TokenText.startswith("//"))
Current.Type = TT_LineComment;
else
Current.Type = TT_BlockComment;
} else if (Current.is(tok::r_paren)) {
if (rParenEndsCast(Current))
Current.Type = TT_CastRParen;
} else if (Current.is(tok::at) && Current.Next) {
switch (Current.Next->Tok.getObjCKeywordID()) {
case tok::objc_interface:
case tok::objc_implementation:
case tok::objc_protocol:
Current.Type = TT_ObjCDecl;
break;
case tok::objc_property:
Current.Type = TT_ObjCProperty;
break;
default:
break;
}
} else if (Current.is(tok::period)) {
FormatToken *PreviousNoComment = Current.getPreviousNonComment();
if (PreviousNoComment &&
PreviousNoComment->isOneOf(tok::comma, tok::l_brace))
Current.Type = TT_DesignatedInitializerPeriod;
} else if (Current.isOneOf(tok::identifier, tok::kw_const) &&
Current.Previous && Current.Previous->isNot(tok::equal) &&
Line.MightBeFunctionDecl && Contexts.size() == 1) {
// Line.MightBeFunctionDecl can only be true after the parentheses of a
// function declaration have been found.
Current.Type = TT_TrailingAnnotation;
}
}
}
/// \brief Take a guess at whether \p Tok starts a name of a function or
/// variable declaration.
///
/// This is a heuristic based on whether \p Tok is an identifier following
/// something that is likely a type.
bool isStartOfName(const FormatToken &Tok) {
if (Tok.isNot(tok::identifier) || !Tok.Previous)
return false;
// Skip "const" as it does not have an influence on whether this is a name.
FormatToken *PreviousNotConst = Tok.Previous;
while (PreviousNotConst && PreviousNotConst->is(tok::kw_const))
PreviousNotConst = PreviousNotConst->Previous;
if (!PreviousNotConst)
return false;
bool IsPPKeyword = PreviousNotConst->is(tok::identifier) &&
PreviousNotConst->Previous &&
PreviousNotConst->Previous->is(tok::hash);
if (PreviousNotConst->Type == TT_TemplateCloser)
return PreviousNotConst && PreviousNotConst->MatchingParen &&
PreviousNotConst->MatchingParen->Previous &&
PreviousNotConst->MatchingParen->Previous->isNot(tok::kw_template);
if (PreviousNotConst->is(tok::r_paren) && PreviousNotConst->MatchingParen &&
PreviousNotConst->MatchingParen->Previous &&
PreviousNotConst->MatchingParen->Previous->is(tok::kw_decltype))
return true;
return (!IsPPKeyword && PreviousNotConst->is(tok::identifier)) ||
PreviousNotConst->Type == TT_PointerOrReference ||
PreviousNotConst->isSimpleTypeSpecifier();
}
/// \brief Determine whether ')' is ending a cast.
bool rParenEndsCast(const FormatToken &Tok) {
FormatToken *LeftOfParens = nullptr;
if (Tok.MatchingParen)
LeftOfParens = Tok.MatchingParen->getPreviousNonComment();
bool IsCast = false;
bool ParensAreEmpty = Tok.Previous == Tok.MatchingParen;
bool ParensAreType = !Tok.Previous ||
Tok.Previous->Type == TT_PointerOrReference ||
Tok.Previous->Type == TT_TemplateCloser ||
Tok.Previous->isSimpleTypeSpecifier();
bool ParensCouldEndDecl =
Tok.Next && Tok.Next->isOneOf(tok::equal, tok::semi, tok::l_brace);
bool IsSizeOfOrAlignOf =
LeftOfParens && LeftOfParens->isOneOf(tok::kw_sizeof, tok::kw_alignof);
if (ParensAreType && !ParensCouldEndDecl && !IsSizeOfOrAlignOf &&
((Contexts.size() > 1 && Contexts[Contexts.size() - 2].IsExpression) ||
(Tok.Next && Tok.Next->isBinaryOperator())))
IsCast = true;
else if (Tok.Next && Tok.Next->isNot(tok::string_literal) &&
(Tok.Next->Tok.isLiteral() ||
Tok.Next->isOneOf(tok::kw_sizeof, tok::kw_alignof)))
IsCast = true;
// If there is an identifier after the (), it is likely a cast, unless
// there is also an identifier before the ().
else if (LeftOfParens &&
(LeftOfParens->Tok.getIdentifierInfo() == nullptr ||
LeftOfParens->is(tok::kw_return)) &&
LeftOfParens->Type != TT_OverloadedOperator &&
LeftOfParens->isNot(tok::at) &&
LeftOfParens->Type != TT_TemplateCloser && Tok.Next) {
if (Tok.Next->isOneOf(tok::identifier, tok::numeric_constant)) {
IsCast = true;
} else {
// Use heuristics to recognize c style casting.
FormatToken *Prev = Tok.Previous;
if (Prev && Prev->isOneOf(tok::amp, tok::star))
Prev = Prev->Previous;
if (Prev && Tok.Next && Tok.Next->Next) {
bool NextIsUnary = Tok.Next->isUnaryOperator() ||
Tok.Next->isOneOf(tok::amp, tok::star);
IsCast = NextIsUnary && Tok.Next->Next->isOneOf(
tok::identifier, tok::numeric_constant);
}
for (; Prev != Tok.MatchingParen; Prev = Prev->Previous) {
if (!Prev || !Prev->isOneOf(tok::kw_const, tok::identifier)) {
IsCast = false;
break;
}
}
}
}
return IsCast && !ParensAreEmpty;
}
/// \brief Return the type of the given token assuming it is * or &.
TokenType determineStarAmpUsage(const FormatToken &Tok, bool IsExpression,
bool InTemplateArgument) {
const FormatToken *PrevToken = Tok.getPreviousNonComment();
if (!PrevToken)
return TT_UnaryOperator;
const FormatToken *NextToken = Tok.getNextNonComment();
if (!NextToken || NextToken->is(tok::l_brace))
return TT_Unknown;
if (PrevToken->is(tok::coloncolon) ||
(PrevToken->is(tok::l_paren) && !IsExpression))
return TT_PointerOrReference;
if (PrevToken->isOneOf(tok::l_paren, tok::l_square, tok::l_brace,
tok::comma, tok::semi, tok::kw_return, tok::colon,
tok::equal, tok::kw_delete, tok::kw_sizeof) ||
PrevToken->Type == TT_BinaryOperator ||
PrevToken->Type == TT_ConditionalExpr ||
PrevToken->Type == TT_UnaryOperator || PrevToken->Type == TT_CastRParen)
return TT_UnaryOperator;
if (NextToken->is(tok::l_square) && NextToken->Type != TT_LambdaLSquare)
return TT_PointerOrReference;
if (NextToken->is(tok::kw_operator))
return TT_PointerOrReference;
if (PrevToken->is(tok::r_paren) && PrevToken->MatchingParen &&
PrevToken->MatchingParen->Previous &&
PrevToken->MatchingParen->Previous->isOneOf(tok::kw_typeof,
tok::kw_decltype))
return TT_PointerOrReference;
if (PrevToken->Tok.isLiteral() ||
PrevToken->isOneOf(tok::r_paren, tok::r_square, tok::kw_true,
tok::kw_false) ||
NextToken->Tok.isLiteral() ||
NextToken->isOneOf(tok::kw_true, tok::kw_false) ||
NextToken->isUnaryOperator() ||
// If we know we're in a template argument, there are no named
// declarations. Thus, having an identifier on the right-hand side
// indicates a binary operator.
(InTemplateArgument && NextToken->Tok.isAnyIdentifier()))
return TT_BinaryOperator;
// This catches some cases where evaluation order is used as control flow:
// aaa && aaa->f();
const FormatToken *NextNextToken = NextToken->getNextNonComment();
if (NextNextToken && NextNextToken->is(tok::arrow))
return TT_BinaryOperator;
// It is very unlikely that we are going to find a pointer or reference type
// definition on the RHS of an assignment.
if (IsExpression)
return TT_BinaryOperator;
return TT_PointerOrReference;
}
TokenType determinePlusMinusCaretUsage(const FormatToken &Tok) {
const FormatToken *PrevToken = Tok.getPreviousNonComment();
if (!PrevToken || PrevToken->Type == TT_CastRParen)
return TT_UnaryOperator;
// Use heuristics to recognize unary operators.
if (PrevToken->isOneOf(tok::equal, tok::l_paren, tok::comma, tok::l_square,
tok::question, tok::colon, tok::kw_return,
tok::kw_case, tok::at, tok::l_brace))
return TT_UnaryOperator;
// There can't be two consecutive binary operators.
if (PrevToken->Type == TT_BinaryOperator)
return TT_UnaryOperator;
// Fall back to marking the token as binary operator.
return TT_BinaryOperator;
}
/// \brief Determine whether ++/-- are pre- or post-increments/-decrements.
TokenType determineIncrementUsage(const FormatToken &Tok) {
const FormatToken *PrevToken = Tok.getPreviousNonComment();
if (!PrevToken || PrevToken->Type == TT_CastRParen)
return TT_UnaryOperator;
if (PrevToken->isOneOf(tok::r_paren, tok::r_square, tok::identifier))
return TT_TrailingUnaryOperator;
return TT_UnaryOperator;
}
SmallVector<Context, 8> Contexts;
const FormatStyle &Style;
AnnotatedLine &Line;
FormatToken *CurrentToken;
bool KeywordVirtualFound;
bool AutoFound;
IdentifierInfo &Ident_in;
};
static int PrecedenceUnaryOperator = prec::PointerToMember + 1;
static int PrecedenceArrowAndPeriod = prec::PointerToMember + 2;
/// \brief Parses binary expressions by inserting fake parenthesis based on
/// operator precedence.
class ExpressionParser {
public:
ExpressionParser(AnnotatedLine &Line) : Current(Line.First) {
// Skip leading "}", e.g. in "} else if (...) {".
if (Current->is(tok::r_brace))
next();
}
/// \brief Parse expressions with the given operatore precedence.
void parse(int Precedence = 0) {
// Skip 'return' and ObjC selector colons as they are not part of a binary
// expression.
while (Current &&
(Current->is(tok::kw_return) ||
(Current->is(tok::colon) && (Current->Type == TT_ObjCMethodExpr ||
Current->Type == TT_DictLiteral))))
next();
if (!Current || Precedence > PrecedenceArrowAndPeriod)
return;
// Conditional expressions need to be parsed separately for proper nesting.
if (Precedence == prec::Conditional) {
parseConditionalExpr();
return;
}
// Parse unary operators, which all have a higher precedence than binary
// operators.
if (Precedence == PrecedenceUnaryOperator) {
parseUnaryOperator();
return;
}
FormatToken *Start = Current;
FormatToken *LatestOperator = nullptr;
unsigned OperatorIndex = 0;
while (Current) {
// Consume operators with higher precedence.
parse(Precedence + 1);
int CurrentPrecedence = getCurrentPrecedence();
if (Current && Current->Type == TT_SelectorName &&
Precedence == CurrentPrecedence) {
if (LatestOperator)
addFakeParenthesis(Start, prec::Level(Precedence));
Start = Current;
}
// At the end of the line or when an operator with higher precedence is
// found, insert fake parenthesis and return.
if (!Current || Current->closesScope() ||
(CurrentPrecedence != -1 && CurrentPrecedence < Precedence)) {
if (LatestOperator) {
LatestOperator->LastOperator = true;
if (Precedence == PrecedenceArrowAndPeriod) {
// Call expressions don't have a binary operator precedence.
addFakeParenthesis(Start, prec::Unknown);
} else {
addFakeParenthesis(Start, prec::Level(Precedence));
}
}
return;
}
// Consume scopes: (), [], <> and {}
if (Current->opensScope()) {
while (Current && !Current->closesScope()) {
next();
parse();
}
next();
} else {
// Operator found.
if (CurrentPrecedence == Precedence) {
LatestOperator = Current;
Current->OperatorIndex = OperatorIndex;
++OperatorIndex;
}
next();
}
}
}
private:
/// \brief Gets the precedence (+1) of the given token for binary operators
/// and other tokens that we treat like binary operators.
int getCurrentPrecedence() {
if (Current) {
if (Current->Type == TT_ConditionalExpr)
return prec::Conditional;
else if (Current->is(tok::semi) || Current->Type == TT_InlineASMColon ||
Current->Type == TT_SelectorName)
return 0;
else if (Current->Type == TT_RangeBasedForLoopColon)
return prec::Comma;
else if (Current->Type == TT_BinaryOperator || Current->is(tok::comma))
return Current->getPrecedence();
else if (Current->isOneOf(tok::period, tok::arrow))
return PrecedenceArrowAndPeriod;
}
return -1;
}
void addFakeParenthesis(FormatToken *Start, prec::Level Precedence) {
Start->FakeLParens.push_back(Precedence);
if (Precedence > prec::Unknown)
Start->StartsBinaryExpression = true;
if (Current) {
++Current->Previous->FakeRParens;
if (Precedence > prec::Unknown)
Current->Previous->EndsBinaryExpression = true;
}
}
/// \brief Parse unary operator expressions and surround them with fake
/// parentheses if appropriate.
void parseUnaryOperator() {
if (!Current || Current->Type != TT_UnaryOperator) {
parse(PrecedenceArrowAndPeriod);
return;
}
FormatToken *Start = Current;
next();
parseUnaryOperator();
// The actual precedence doesn't matter.
addFakeParenthesis(Start, prec::Unknown);
}
void parseConditionalExpr() {
FormatToken *Start = Current;
parse(prec::LogicalOr);
if (!Current || !Current->is(tok::question))
return;
next();
parse(prec::LogicalOr);
if (!Current || Current->Type != TT_ConditionalExpr)
return;
next();
parseConditionalExpr();
addFakeParenthesis(Start, prec::Conditional);
}
void next() {
if (Current)
Current = Current->Next;
while (Current && Current->isTrailingComment())
Current = Current->Next;
}
FormatToken *Current;
};
} // end anonymous namespace
void
TokenAnnotator::setCommentLineLevels(SmallVectorImpl<AnnotatedLine *> &Lines) {
const AnnotatedLine *NextNonCommentLine = nullptr;
for (SmallVectorImpl<AnnotatedLine *>::reverse_iterator I = Lines.rbegin(),
E = Lines.rend();
I != E; ++I) {
if (NextNonCommentLine && (*I)->First->is(tok::comment) &&
(*I)->First->Next == nullptr)
(*I)->Level = NextNonCommentLine->Level;
else
NextNonCommentLine = (*I)->First->isNot(tok::r_brace) ? (*I) : nullptr;
setCommentLineLevels((*I)->Children);
}
}
void TokenAnnotator::annotate(AnnotatedLine &Line) {
for (SmallVectorImpl<AnnotatedLine *>::iterator I = Line.Children.begin(),
E = Line.Children.end();
I != E; ++I) {
annotate(**I);
}
AnnotatingParser Parser(Style, Line, Ident_in);
Line.Type = Parser.parseLine();
if (Line.Type == LT_Invalid)
return;
ExpressionParser ExprParser(Line);
ExprParser.parse();
if (Line.First->Type == TT_ObjCMethodSpecifier)
Line.Type = LT_ObjCMethodDecl;
else if (Line.First->Type == TT_ObjCDecl)
Line.Type = LT_ObjCDecl;
else if (Line.First->Type == TT_ObjCProperty)
Line.Type = LT_ObjCProperty;
Line.First->SpacesRequiredBefore = 1;
Line.First->CanBreakBefore = Line.First->MustBreakBefore;
}
// This function heuristically determines whether 'Current' starts the name of a
// function declaration.
static bool isFunctionDeclarationName(const FormatToken &Current) {
if (Current.Type != TT_StartOfName ||
Current.NestingLevel != 0 ||
Current.Previous->Type == TT_StartOfName)
return false;
const FormatToken *Next = Current.Next;
for (; Next; Next = Next->Next) {
if (Next->Type == TT_TemplateOpener) {
Next = Next->MatchingParen;
} else if (Next->is(tok::coloncolon)) {
Next = Next->Next;
if (!Next || !Next->is(tok::identifier))
return false;
} else if (Next->is(tok::l_paren)) {
break;
} else {
return false;
}
}
if (!Next)
return false;
assert(Next->is(tok::l_paren));
if (Next->Next == Next->MatchingParen)
return true;
for (const FormatToken *Tok = Next->Next; Tok != Next->MatchingParen;
Tok = Tok->Next) {
if (Tok->is(tok::kw_const) || Tok->isSimpleTypeSpecifier() ||
Tok->Type == TT_PointerOrReference || Tok->Type == TT_StartOfName)
return true;
if (Tok->isOneOf(tok::l_brace, tok::string_literal) || Tok->Tok.isLiteral())
return false;
}
return false;
}
void TokenAnnotator::calculateFormattingInformation(AnnotatedLine &Line) {
for (SmallVectorImpl<AnnotatedLine *>::iterator I = Line.Children.begin(),
E = Line.Children.end();
I != E; ++I) {
calculateFormattingInformation(**I);
}
Line.First->TotalLength =
Line.First->IsMultiline ? Style.ColumnLimit : Line.First->ColumnWidth;
if (!Line.First->Next)
return;
FormatToken *Current = Line.First->Next;
bool InFunctionDecl = Line.MightBeFunctionDecl;
while (Current) {
if (isFunctionDeclarationName(*Current))
Current->Type = TT_FunctionDeclarationName;
if (Current->Type == TT_LineComment) {
if (Current->Previous->BlockKind == BK_BracedInit &&
Current->Previous->opensScope())
Current->SpacesRequiredBefore = Style.Cpp11BracedListStyle ? 0 : 1;
else
Current->SpacesRequiredBefore = Style.SpacesBeforeTrailingComments;
// If we find a trailing comment, iterate backwards to determine whether
// it seems to relate to a specific parameter. If so, break before that
// parameter to avoid changing the comment's meaning. E.g. don't move 'b'
// to the previous line in:
// SomeFunction(a,
// b, // comment
// c);
if (!Current->HasUnescapedNewline) {
for (FormatToken *Parameter = Current->Previous; Parameter;
Parameter = Parameter->Previous) {
if (Parameter->isOneOf(tok::comment, tok::r_brace))
break;
if (Parameter->Previous && Parameter->Previous->is(tok::comma)) {
if (Parameter->Previous->Type != TT_CtorInitializerComma &&
Parameter->HasUnescapedNewline)
Parameter->MustBreakBefore = true;
break;
}
}
}
} else if (Current->SpacesRequiredBefore == 0 &&
spaceRequiredBefore(Line, *Current)) {
Current->SpacesRequiredBefore = 1;
}
Current->MustBreakBefore =
Current->MustBreakBefore || mustBreakBefore(Line, *Current);
Current->CanBreakBefore =
Current->MustBreakBefore || canBreakBefore(Line, *Current);
unsigned ChildSize = 0;
if (Current->Previous->Children.size() == 1) {
FormatToken &LastOfChild = *Current->Previous->Children[0]->Last;
ChildSize = LastOfChild.isTrailingComment() ? Style.ColumnLimit
: LastOfChild.TotalLength + 1;
}
if (Current->MustBreakBefore || Current->Previous->Children.size() > 1 ||
Current->IsMultiline)
Current->TotalLength = Current->Previous->TotalLength + Style.ColumnLimit;
else
Current->TotalLength = Current->Previous->TotalLength +
Current->ColumnWidth + ChildSize +
Current->SpacesRequiredBefore;
if (Current->Type == TT_CtorInitializerColon)
InFunctionDecl = false;
// FIXME: Only calculate this if CanBreakBefore is true once static
// initializers etc. are sorted out.
// FIXME: Move magic numbers to a better place.
Current->SplitPenalty = 20 * Current->BindingStrength +
splitPenalty(Line, *Current, InFunctionDecl);
Current = Current->Next;
}
calculateUnbreakableTailLengths(Line);
for (Current = Line.First; Current != nullptr; Current = Current->Next) {
if (Current->Role)
Current->Role->precomputeFormattingInfos(Current);
}
DEBUG({ printDebugInfo(Line); });
}
void TokenAnnotator::calculateUnbreakableTailLengths(AnnotatedLine &Line) {
unsigned UnbreakableTailLength = 0;
FormatToken *Current = Line.Last;
while (Current) {
Current->UnbreakableTailLength = UnbreakableTailLength;
if (Current->CanBreakBefore ||
Current->isOneOf(tok::comment, tok::string_literal)) {
UnbreakableTailLength = 0;
} else {
UnbreakableTailLength +=
Current->ColumnWidth + Current->SpacesRequiredBefore;
}
Current = Current->Previous;
}
}
unsigned TokenAnnotator::splitPenalty(const AnnotatedLine &Line,
const FormatToken &Tok,
bool InFunctionDecl) {
const FormatToken &Left = *Tok.Previous;
const FormatToken &Right = Tok;
if (Left.is(tok::semi))
return 0;
if (Left.is(tok::comma) || (Right.is(tok::identifier) && Right.Next &&
Right.Next->Type == TT_DictLiteral))
return 1;
if (Right.is(tok::l_square)) {
if (Style.Language == FormatStyle::LK_Proto)
return 1;
if (Right.Type != TT_ObjCMethodExpr && Right.Type != TT_LambdaLSquare)
return 500;
}
if (Right.Type == TT_StartOfName ||
Right.Type == TT_FunctionDeclarationName || Right.is(tok::kw_operator)) {
if (Line.First->is(tok::kw_for) && Right.PartOfMultiVariableDeclStmt)
return 3;
if (Left.Type == TT_StartOfName)
return 20;
if (InFunctionDecl && Right.NestingLevel == 0)
return Style.PenaltyReturnTypeOnItsOwnLine;
return 200;
}
if (Left.is(tok::equal) && Right.is(tok::l_brace))
return 150;
if (Left.Type == TT_CastRParen)
return 100;
if (Left.is(tok::coloncolon) ||
(Right.is(tok::period) && Style.Language == FormatStyle::LK_Proto))
return 500;
if (Left.isOneOf(tok::kw_class, tok::kw_struct))
return 5000;
if (Left.Type == TT_RangeBasedForLoopColon ||
Left.Type == TT_InheritanceColon)
return 2;
if (Right.isMemberAccess()) {
if (Left.is(tok::r_paren) && Left.MatchingParen &&
Left.MatchingParen->ParameterCount > 0)
return 20; // Should be smaller than breaking at a nested comma.
return 150;
}
if (Right.Type == TT_TrailingAnnotation &&
(!Right.Next || Right.Next->isNot(tok::l_paren))) {
// Generally, breaking before a trailing annotation is bad unless it is
// function-like. It seems to be especially preferable to keep standard
// annotations (i.e. "const", "final" and "override") on the same line.
// Use a slightly higher penalty after ")" so that annotations like
// "const override" are kept together.
bool is_short_annotation = Right.TokenText.size() < 10;
return (Left.is(tok::r_paren) ? 100 : 120) + (is_short_annotation ? 50 : 0);
}
// In for-loops, prefer breaking at ',' and ';'.
if (Line.First->is(tok::kw_for) && Left.is(tok::equal))
return 4;
// In Objective-C method expressions, prefer breaking before "param:" over
// breaking after it.
if (Right.Type == TT_SelectorName)
return 0;
if (Left.is(tok::colon) && Left.Type == TT_ObjCMethodExpr)
return Line.MightBeFunctionDecl ? 50 : 500;
if (Left.is(tok::l_paren) && InFunctionDecl)
return 100;
if (Left.is(tok::equal) && InFunctionDecl)
return 110;
if (Left.opensScope())
return Left.ParameterCount > 1 ? Style.PenaltyBreakBeforeFirstCallParameter
: 19;
if (Right.is(tok::lessless)) {
if (Left.is(tok::string_literal)) {
StringRef Content = Left.TokenText;
if (Content.startswith("\""))
Content = Content.drop_front(1);
if (Content.endswith("\""))
Content = Content.drop_back(1);
Content = Content.trim();
if (Content.size() > 1 &&
(Content.back() == ':' || Content.back() == '='))
return 25;
}
return 1; // Breaking at a << is really cheap.
}
if (Left.Type == TT_ConditionalExpr)
return prec::Conditional;
prec::Level Level = Left.getPrecedence();
if (Level != prec::Unknown)
return Level;
return 3;
}
bool TokenAnnotator::spaceRequiredBetween(const AnnotatedLine &Line,
const FormatToken &Left,
const FormatToken &Right) {
if (Style.Language == FormatStyle::LK_Proto) {
if (Right.is(tok::period) &&
(Left.TokenText == "optional" || Left.TokenText == "required" ||
Left.TokenText == "repeated"))
return true;
if (Right.is(tok::l_paren) &&
(Left.TokenText == "returns" || Left.TokenText == "option"))
return true;
} else if (Style.Language == FormatStyle::LK_JavaScript) {
if (Left.TokenText == "var")
return true;
}
if (Left.is(tok::kw_return) && Right.isNot(tok::semi))
return true;
if (Style.ObjCSpaceAfterProperty && Line.Type == LT_ObjCProperty &&
Left.Tok.getObjCKeywordID() == tok::objc_property)
return true;
if (Right.is(tok::hashhash))
return Left.is(tok::hash);
if (Left.isOneOf(tok::hashhash, tok::hash))
return Right.is(tok::hash);
if (Left.is(tok::l_paren) && Right.is(tok::r_paren))
return Style.SpaceInEmptyParentheses;
if (Left.is(tok::l_paren) || Right.is(tok::r_paren))
return (Right.Type == TT_CastRParen ||
(Left.MatchingParen && Left.MatchingParen->Type == TT_CastRParen))
? Style.SpacesInCStyleCastParentheses
: Style.SpacesInParentheses;
if (Style.SpacesInAngles &&
((Left.Type == TT_TemplateOpener) != (Right.Type == TT_TemplateCloser)))
return true;
if (Right.isOneOf(tok::semi, tok::comma))
return false;
if (Right.is(tok::less) &&
(Left.is(tok::kw_template) ||
(Line.Type == LT_ObjCDecl && Style.ObjCSpaceBeforeProtocolList)))
return true;
if (Left.is(tok::arrow) || Right.is(tok::arrow))
return false;
if (Left.isOneOf(tok::exclaim, tok::tilde))
return false;
if (Left.is(tok::at) &&
Right.isOneOf(tok::identifier, tok::string_literal, tok::char_constant,
tok::numeric_constant, tok::l_paren, tok::l_brace,
tok::kw_true, tok::kw_false))
return false;
if (Left.is(tok::coloncolon))
return false;
if (Right.is(tok::coloncolon) && Left.isNot(tok::l_brace))
return (Left.is(tok::less) && Style.Standard == FormatStyle::LS_Cpp03) ||
!Left.isOneOf(tok::identifier, tok::greater, tok::l_paren,
tok::r_paren, tok::less);
if (Left.is(tok::less) || Right.isOneOf(tok::greater, tok::less))
return false;
if (Right.is(tok::ellipsis))
return Left.Tok.isLiteral();
if (Left.is(tok::l_square) && Right.is(tok::amp))
return false;
if (Right.Type == TT_PointerOrReference)
return Left.Tok.isLiteral() ||
((Left.Type != TT_PointerOrReference) && Left.isNot(tok::l_paren) &&
Style.PointerAlignment != FormatStyle::PAS_Left);
if (Right.Type == TT_FunctionTypeLParen && Left.isNot(tok::l_paren) &&
(Left.Type != TT_PointerOrReference || Style.PointerAlignment != FormatStyle::PAS_Right))
return true;
if (Left.Type == TT_PointerOrReference)
return Right.Tok.isLiteral() || Right.Type == TT_BlockComment ||
((Right.Type != TT_PointerOrReference) &&
Right.isNot(tok::l_paren) && Style.PointerAlignment != FormatStyle::PAS_Right &&
Left.Previous &&
!Left.Previous->isOneOf(tok::l_paren, tok::coloncolon));
if (Right.is(tok::star) && Left.is(tok::l_paren))
return false;
if (Left.is(tok::l_square))
return Left.Type == TT_ArrayInitializerLSquare &&
Style.SpacesInContainerLiterals && Right.isNot(tok::r_square);
if (Right.is(tok::r_square))
return Right.MatchingParen && Style.SpacesInContainerLiterals &&
Right.MatchingParen->Type == TT_ArrayInitializerLSquare;
if (Right.is(tok::l_square) && Right.Type != TT_ObjCMethodExpr &&
Right.Type != TT_LambdaLSquare && Left.isNot(tok::numeric_constant) &&
Left.Type != TT_DictLiteral)
return false;
if (Left.is(tok::colon))
return Left.Type != TT_ObjCMethodExpr;
if (Left.Type == TT_BlockComment)
return !Left.TokenText.endswith("=*/");
if (Right.is(tok::l_paren)) {
if (Left.is(tok::r_paren) && Left.Type == TT_AttributeParen)
return true;
return Line.Type == LT_ObjCDecl ||
Left.isOneOf(tok::kw_new, tok::kw_delete, tok::semi) ||
(Style.SpaceBeforeParens != FormatStyle::SBPO_Never &&
(Left.isOneOf(tok::kw_if, tok::kw_for, tok::kw_while,
tok::kw_switch, tok::kw_catch, tok::kw_case) ||
Left.IsForEachMacro)) ||
(Style.SpaceBeforeParens == FormatStyle::SBPO_Always &&
Left.isOneOf(tok::identifier, tok::kw___attribute) &&
Line.Type != LT_PreprocessorDirective);
}
if (Left.is(tok::at) && Right.Tok.getObjCKeywordID() != tok::objc_not_keyword)
return false;
if (Left.is(tok::l_brace) && Right.is(tok::r_brace))
return !Left.Children.empty(); // No spaces in "{}".
if ((Left.is(tok::l_brace) && Left.BlockKind != BK_Block) ||
(Right.is(tok::r_brace) && Right.MatchingParen &&
Right.MatchingParen->BlockKind != BK_Block))
return !Style.Cpp11BracedListStyle;
if (Right.Type == TT_UnaryOperator)
return !Left.isOneOf(tok::l_paren, tok::l_square, tok::at) &&
(Left.isNot(tok::colon) || Left.Type != TT_ObjCMethodExpr);
if ((Left.isOneOf(tok::identifier, tok::greater, tok::r_square,
tok::r_paren) ||
Left.isSimpleTypeSpecifier()) &&
Right.is(tok::l_brace) && Right.getNextNonComment() &&
Right.BlockKind != BK_Block)
return false;
if (Left.is(tok::period) || Right.is(tok::period))
return false;
if (Right.is(tok::hash) && Left.is(tok::identifier) && Left.TokenText == "L")
return false;
return true;
}
bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
const FormatToken &Tok) {
if (Tok.Tok.getIdentifierInfo() && Tok.Previous->Tok.getIdentifierInfo())
return true; // Never ever merge two identifiers.
if (Tok.Previous->Type == TT_ImplicitStringLiteral)
return Tok.WhitespaceRange.getBegin() != Tok.WhitespaceRange.getEnd();
if (Line.Type == LT_ObjCMethodDecl) {
if (Tok.Previous->Type == TT_ObjCMethodSpecifier)
return true;
if (Tok.Previous->is(tok::r_paren) && Tok.is(tok::identifier))
// Don't space between ')' and <id>
return false;
}
if (Line.Type == LT_ObjCProperty &&
(Tok.is(tok::equal) || Tok.Previous->is(tok::equal)))
return false;
if (Tok.Type == TT_TrailingReturnArrow ||
Tok.Previous->Type == TT_TrailingReturnArrow)
return true;
if (Tok.Previous->is(tok::comma))
return true;
if (Tok.is(tok::comma))
return false;
if (Tok.Type == TT_CtorInitializerColon || Tok.Type == TT_ObjCBlockLParen)
return true;
if (Tok.Previous->Tok.is(tok::kw_operator))
return Tok.is(tok::coloncolon);
if (Tok.Type == TT_OverloadedOperatorLParen)
return false;
if (Tok.is(tok::colon))
return !Line.First->isOneOf(tok::kw_case, tok::kw_default) &&
Tok.getNextNonComment() && Tok.Type != TT_ObjCMethodExpr &&
!Tok.Previous->is(tok::question) &&
(Tok.Type != TT_DictLiteral || Style.SpacesInContainerLiterals);
if (Tok.Previous->Type == TT_UnaryOperator ||
Tok.Previous->Type == TT_CastRParen)
return Tok.Type == TT_BinaryOperator;
if (Tok.Previous->is(tok::greater) && Tok.is(tok::greater)) {
return Tok.Type == TT_TemplateCloser &&
Tok.Previous->Type == TT_TemplateCloser &&
(Style.Standard != FormatStyle::LS_Cpp11 || Style.SpacesInAngles);
}
if (Tok.isOneOf(tok::arrowstar, tok::periodstar) ||
Tok.Previous->isOneOf(tok::arrowstar, tok::periodstar))
return false;
if (!Style.SpaceBeforeAssignmentOperators &&
Tok.getPrecedence() == prec::Assignment)
return false;
if ((Tok.Type == TT_BinaryOperator && !Tok.Previous->is(tok::l_paren)) ||
Tok.Previous->Type == TT_BinaryOperator ||
Tok.Previous->Type == TT_ConditionalExpr)
return true;
if (Tok.Previous->Type == TT_TemplateCloser && Tok.is(tok::l_paren))
return false;
if (Tok.is(tok::less) && Tok.Previous->isNot(tok::l_paren) &&
Line.First->is(tok::hash))
return true;
if (Tok.Type == TT_TrailingUnaryOperator)
return false;
if (Tok.Previous->Type == TT_RegexLiteral)
return false;
return spaceRequiredBetween(Line, *Tok.Previous, Tok);
}
// Returns 'true' if 'Tok' is a brace we'd want to break before in Allman style.
static bool isAllmanBrace(const FormatToken &Tok) {
return Tok.is(tok::l_brace) && Tok.BlockKind == BK_Block &&
Tok.Type != TT_ObjCBlockLBrace && Tok.Type != TT_DictLiteral;
}
bool TokenAnnotator::mustBreakBefore(const AnnotatedLine &Line,
const FormatToken &Right) {
const FormatToken &Left = *Right.Previous;
if (Right.NewlinesBefore > 1)
return true;
if (Right.is(tok::comment)) {
return Right.Previous->BlockKind != BK_BracedInit &&
Right.Previous->Type != TT_CtorInitializerColon &&
(Right.NewlinesBefore > 0 && Right.HasUnescapedNewline);
} else if (Right.Previous->isTrailingComment() ||
(Right.isStringLiteral() && Right.Previous->isStringLiteral())) {
return true;
} else if (Right.Previous->IsUnterminatedLiteral) {
return true;
} else if (Right.is(tok::lessless) && Right.Next &&
Right.Previous->is(tok::string_literal) &&
Right.Next->is(tok::string_literal)) {
return true;
} else if (Right.Previous->ClosesTemplateDeclaration &&
Right.Previous->MatchingParen &&
Right.Previous->MatchingParen->NestingLevel == 0 &&
Style.AlwaysBreakTemplateDeclarations) {
return true;
} else if ((Right.Type == TT_CtorInitializerComma ||
Right.Type == TT_CtorInitializerColon) &&
Style.BreakConstructorInitializersBeforeComma &&
!Style.ConstructorInitializerAllOnOneLineOrOnePerLine) {
return true;
} else if (Right.is(tok::string_literal) &&
Right.TokenText.startswith("R\"")) {
// Raw string literals are special wrt. line breaks. The author has made a
// deliberate choice and might have aligned the contents of the string
// literal accordingly. Thus, we try keep existing line breaks.
return Right.NewlinesBefore > 0;
} else if (Right.Previous->is(tok::l_brace) && Right.NestingLevel == 1 &&
Style.Language == FormatStyle::LK_Proto) {
// Don't enums onto single lines in protocol buffers.
return true;
} else if (isAllmanBrace(Left) || isAllmanBrace(Right)) {
return Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
Style.BreakBeforeBraces == FormatStyle::BS_GNU;
}
// If the last token before a '}' is a comma or a comment, the intention is to
// insert a line break after it in order to make shuffling around entries
// easier.
const FormatToken *BeforeClosingBrace = nullptr;
if (Left.is(tok::l_brace) && Left.MatchingParen)
BeforeClosingBrace = Left.MatchingParen->Previous;
else if (Right.is(tok::r_brace))
BeforeClosingBrace = Right.Previous;
if (BeforeClosingBrace &&
BeforeClosingBrace->isOneOf(tok::comma, tok::comment))
return true;
if (Style.Language == FormatStyle::LK_JavaScript) {
// FIXME: This might apply to other languages and token kinds.
if (Right.is(tok::char_constant) && Left.is(tok::plus) && Left.Previous &&
Left.Previous->is(tok::char_constant))
return true;
}
return false;
}
bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
const FormatToken &Right) {
const FormatToken &Left = *Right.Previous;
if (Left.is(tok::at))
return false;
if (Left.Tok.getObjCKeywordID() == tok::objc_interface)
return false;
if (Right.Type == TT_StartOfName ||
Right.Type == TT_FunctionDeclarationName || Right.is(tok::kw_operator))
return true;
if (Right.isTrailingComment())
// We rely on MustBreakBefore being set correctly here as we should not
// change the "binding" behavior of a comment.
// The first comment in a braced lists is always interpreted as belonging to
// the first list element. Otherwise, it should be placed outside of the
// list.
return Left.BlockKind == BK_BracedInit;
if (Left.is(tok::question) && Right.is(tok::colon))
return false;
if (Right.Type == TT_ConditionalExpr || Right.is(tok::question))
return Style.BreakBeforeTernaryOperators;
if (Left.Type == TT_ConditionalExpr || Left.is(tok::question))
return !Style.BreakBeforeTernaryOperators;
if (Right.Type == TT_InheritanceColon)
return true;
if (Right.is(tok::colon) && (Right.Type != TT_CtorInitializerColon &&
Right.Type != TT_InlineASMColon))
return false;
if (Left.is(tok::colon) &&
(Left.Type == TT_DictLiteral || Left.Type == TT_ObjCMethodExpr))
return true;
if (Right.Type == TT_SelectorName)
return true;
if (Left.is(tok::r_paren) && Line.Type == LT_ObjCProperty)
return true;
if (Left.ClosesTemplateDeclaration)
return true;
if (Right.Type == TT_RangeBasedForLoopColon ||
Right.Type == TT_OverloadedOperatorLParen ||
Right.Type == TT_OverloadedOperator)
return false;
if (Left.Type == TT_RangeBasedForLoopColon)
return true;
if (Right.Type == TT_RangeBasedForLoopColon)
return false;
if (Left.Type == TT_PointerOrReference || Left.Type == TT_TemplateCloser ||
Left.Type == TT_UnaryOperator || Left.is(tok::kw_operator))
return false;
if (Left.is(tok::equal) && Line.Type == LT_VirtualFunctionDecl)
return false;
if (Left.is(tok::l_paren) && Left.Type == TT_AttributeParen)
return false;
if (Left.is(tok::l_paren) && Left.Previous &&
(Left.Previous->Type == TT_BinaryOperator ||
Left.Previous->Type == TT_CastRParen || Left.Previous->is(tok::kw_if)))
return false;
if (Right.Type == TT_ImplicitStringLiteral)
return false;
if (Right.is(tok::r_paren) || Right.Type == TT_TemplateCloser)
return false;
// We only break before r_brace if there was a corresponding break before
// the l_brace, which is tracked by BreakBeforeClosingBrace.
if (Right.is(tok::r_brace))
return Right.MatchingParen && Right.MatchingParen->BlockKind == BK_Block;
// Allow breaking after a trailing annotation, e.g. after a method
// declaration.
if (Left.Type == TT_TrailingAnnotation)
return !Right.isOneOf(tok::l_brace, tok::semi, tok::equal, tok::l_paren,
tok::less, tok::coloncolon);
if (Right.is(tok::kw___attribute))
return true;
if (Left.is(tok::identifier) && Right.is(tok::string_literal))
return true;
if (Right.is(tok::identifier) && Right.Next &&
Right.Next->Type == TT_DictLiteral)
return true;
if (Left.Type == TT_CtorInitializerComma &&
Style.BreakConstructorInitializersBeforeComma)
return false;
if (Right.Type == TT_CtorInitializerComma &&
Style.BreakConstructorInitializersBeforeComma)
return true;
if (Left.is(tok::greater) && Right.is(tok::greater) &&
Left.Type != TT_TemplateCloser)
return false;
if (Right.Type == TT_BinaryOperator && Style.BreakBeforeBinaryOperators)
return true;
if (Left.Type == TT_ArrayInitializerLSquare)
return true;
return (Left.isBinaryOperator() &&
!Left.isOneOf(tok::arrowstar, tok::lessless) &&
!Style.BreakBeforeBinaryOperators) ||
Left.isOneOf(tok::comma, tok::coloncolon, tok::semi, tok::l_brace,
tok::kw_class, tok::kw_struct) ||
Right.isMemberAccess() ||
Right.isOneOf(tok::lessless, tok::colon, tok::l_square, tok::at) ||
(Left.is(tok::r_paren) &&
Right.isOneOf(tok::identifier, tok::kw_const)) ||
(Left.is(tok::l_paren) && !Right.is(tok::r_paren));
}
void TokenAnnotator::printDebugInfo(const AnnotatedLine &Line) {
llvm::errs() << "AnnotatedTokens:\n";
const FormatToken *Tok = Line.First;
while (Tok) {
llvm::errs() << " M=" << Tok->MustBreakBefore
<< " C=" << Tok->CanBreakBefore << " T=" << Tok->Type
<< " S=" << Tok->SpacesRequiredBefore
<< " B=" << Tok->BlockParameterCount
<< " P=" << Tok->SplitPenalty << " Name=" << Tok->Tok.getName()
<< " L=" << Tok->TotalLength << " PPK=" << Tok->PackingKind
<< " FakeLParens=";
for (unsigned i = 0, e = Tok->FakeLParens.size(); i != e; ++i)
llvm::errs() << Tok->FakeLParens[i] << "/";
llvm::errs() << " FakeRParens=" << Tok->FakeRParens << "\n";
if (!Tok->Next)
assert(Tok == Line.Last);
Tok = Tok->Next;
}
llvm::errs() << "----\n";
}
} // namespace format
} // namespace clang