minix/external/bsd/llvm/dist/clang/lib/Format/UnwrappedLineParser.cpp
Lionel Sambuc f4a2713ac8 Importing netbsd clang -- pristine
Change-Id: Ia40e9ffdf29b5dab2f122f673ff6802a58bc690f
2014-07-28 17:05:57 +02:00

1356 lines
39 KiB
C++

//===--- UnwrappedLineParser.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 contains the implementation of the UnwrappedLineParser,
/// which turns a stream of tokens into UnwrappedLines.
///
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "format-parser"
#include "UnwrappedLineParser.h"
#include "llvm/Support/Debug.h"
namespace clang {
namespace format {
class FormatTokenSource {
public:
virtual ~FormatTokenSource() {}
virtual FormatToken *getNextToken() = 0;
virtual unsigned getPosition() = 0;
virtual FormatToken *setPosition(unsigned Position) = 0;
};
namespace {
class ScopedDeclarationState {
public:
ScopedDeclarationState(UnwrappedLine &Line, std::vector<bool> &Stack,
bool MustBeDeclaration)
: Line(Line), Stack(Stack) {
Line.MustBeDeclaration = MustBeDeclaration;
Stack.push_back(MustBeDeclaration);
}
~ScopedDeclarationState() {
Stack.pop_back();
if (!Stack.empty())
Line.MustBeDeclaration = Stack.back();
else
Line.MustBeDeclaration = true;
}
private:
UnwrappedLine &Line;
std::vector<bool> &Stack;
};
class ScopedMacroState : public FormatTokenSource {
public:
ScopedMacroState(UnwrappedLine &Line, FormatTokenSource *&TokenSource,
FormatToken *&ResetToken, bool &StructuralError)
: Line(Line), TokenSource(TokenSource), ResetToken(ResetToken),
PreviousLineLevel(Line.Level), PreviousTokenSource(TokenSource),
StructuralError(StructuralError),
PreviousStructuralError(StructuralError), Token(NULL) {
TokenSource = this;
Line.Level = 0;
Line.InPPDirective = true;
}
~ScopedMacroState() {
TokenSource = PreviousTokenSource;
ResetToken = Token;
Line.InPPDirective = false;
Line.Level = PreviousLineLevel;
StructuralError = PreviousStructuralError;
}
virtual FormatToken *getNextToken() {
// The \c UnwrappedLineParser guards against this by never calling
// \c getNextToken() after it has encountered the first eof token.
assert(!eof());
Token = PreviousTokenSource->getNextToken();
if (eof())
return getFakeEOF();
return Token;
}
virtual unsigned getPosition() { return PreviousTokenSource->getPosition(); }
virtual FormatToken *setPosition(unsigned Position) {
Token = PreviousTokenSource->setPosition(Position);
return Token;
}
private:
bool eof() { return Token && Token->HasUnescapedNewline; }
FormatToken *getFakeEOF() {
static bool EOFInitialized = false;
static FormatToken FormatTok;
if (!EOFInitialized) {
FormatTok.Tok.startToken();
FormatTok.Tok.setKind(tok::eof);
EOFInitialized = true;
}
return &FormatTok;
}
UnwrappedLine &Line;
FormatTokenSource *&TokenSource;
FormatToken *&ResetToken;
unsigned PreviousLineLevel;
FormatTokenSource *PreviousTokenSource;
bool &StructuralError;
bool PreviousStructuralError;
FormatToken *Token;
};
} // end anonymous namespace
class ScopedLineState {
public:
ScopedLineState(UnwrappedLineParser &Parser,
bool SwitchToPreprocessorLines = false)
: Parser(Parser) {
OriginalLines = Parser.CurrentLines;
if (SwitchToPreprocessorLines)
Parser.CurrentLines = &Parser.PreprocessorDirectives;
else if (!Parser.Line->Tokens.empty())
Parser.CurrentLines = &Parser.Line->Tokens.back().Children;
PreBlockLine = Parser.Line.take();
Parser.Line.reset(new UnwrappedLine());
Parser.Line->Level = PreBlockLine->Level;
Parser.Line->InPPDirective = PreBlockLine->InPPDirective;
}
~ScopedLineState() {
if (!Parser.Line->Tokens.empty()) {
Parser.addUnwrappedLine();
}
assert(Parser.Line->Tokens.empty());
Parser.Line.reset(PreBlockLine);
if (Parser.CurrentLines == &Parser.PreprocessorDirectives)
Parser.MustBreakBeforeNextToken = true;
Parser.CurrentLines = OriginalLines;
}
private:
UnwrappedLineParser &Parser;
UnwrappedLine *PreBlockLine;
SmallVectorImpl<UnwrappedLine> *OriginalLines;
};
namespace {
class IndexedTokenSource : public FormatTokenSource {
public:
IndexedTokenSource(ArrayRef<FormatToken *> Tokens)
: Tokens(Tokens), Position(-1) {}
virtual FormatToken *getNextToken() {
++Position;
return Tokens[Position];
}
virtual unsigned getPosition() {
assert(Position >= 0);
return Position;
}
virtual FormatToken *setPosition(unsigned P) {
Position = P;
return Tokens[Position];
}
void reset() { Position = -1; }
private:
ArrayRef<FormatToken *> Tokens;
int Position;
};
} // end anonymous namespace
UnwrappedLineParser::UnwrappedLineParser(const FormatStyle &Style,
ArrayRef<FormatToken *> Tokens,
UnwrappedLineConsumer &Callback)
: Line(new UnwrappedLine), MustBreakBeforeNextToken(false),
CurrentLines(&Lines), StructuralError(false), Style(Style), Tokens(NULL),
Callback(Callback), AllTokens(Tokens), PPBranchLevel(-1) {}
void UnwrappedLineParser::reset() {
PPBranchLevel = -1;
Line.reset(new UnwrappedLine);
CommentsBeforeNextToken.clear();
FormatTok = NULL;
MustBreakBeforeNextToken = false;
PreprocessorDirectives.clear();
CurrentLines = &Lines;
DeclarationScopeStack.clear();
StructuralError = false;
PPStack.clear();
}
bool UnwrappedLineParser::parse() {
IndexedTokenSource TokenSource(AllTokens);
do {
DEBUG(llvm::dbgs() << "----\n");
reset();
Tokens = &TokenSource;
TokenSource.reset();
readToken();
parseFile();
// Create line with eof token.
pushToken(FormatTok);
addUnwrappedLine();
for (SmallVectorImpl<UnwrappedLine>::iterator I = Lines.begin(),
E = Lines.end();
I != E; ++I) {
Callback.consumeUnwrappedLine(*I);
}
Callback.finishRun();
Lines.clear();
while (!PPLevelBranchIndex.empty() &&
PPLevelBranchIndex.back() + 1 >= PPLevelBranchCount.back()) {
PPLevelBranchIndex.resize(PPLevelBranchIndex.size() - 1);
PPLevelBranchCount.resize(PPLevelBranchCount.size() - 1);
}
if (!PPLevelBranchIndex.empty()) {
++PPLevelBranchIndex.back();
assert(PPLevelBranchIndex.size() == PPLevelBranchCount.size());
assert(PPLevelBranchIndex.back() <= PPLevelBranchCount.back());
}
} while (!PPLevelBranchIndex.empty());
return StructuralError;
}
void UnwrappedLineParser::parseFile() {
ScopedDeclarationState DeclarationState(
*Line, DeclarationScopeStack,
/*MustBeDeclaration=*/ !Line->InPPDirective);
parseLevel(/*HasOpeningBrace=*/false);
// Make sure to format the remaining tokens.
flushComments(true);
addUnwrappedLine();
}
void UnwrappedLineParser::parseLevel(bool HasOpeningBrace) {
bool SwitchLabelEncountered = false;
do {
switch (FormatTok->Tok.getKind()) {
case tok::comment:
nextToken();
addUnwrappedLine();
break;
case tok::l_brace:
// FIXME: Add parameter whether this can happen - if this happens, we must
// be in a non-declaration context.
parseBlock(/*MustBeDeclaration=*/false);
addUnwrappedLine();
break;
case tok::r_brace:
if (HasOpeningBrace)
return;
StructuralError = true;
nextToken();
addUnwrappedLine();
break;
case tok::kw_default:
case tok::kw_case:
if (!SwitchLabelEncountered &&
(Style.IndentCaseLabels || (Line->InPPDirective && Line->Level == 1)))
++Line->Level;
SwitchLabelEncountered = true;
parseStructuralElement();
break;
default:
parseStructuralElement();
break;
}
} while (!eof());
}
void UnwrappedLineParser::calculateBraceTypes() {
// We'll parse forward through the tokens until we hit
// a closing brace or eof - note that getNextToken() will
// parse macros, so this will magically work inside macro
// definitions, too.
unsigned StoredPosition = Tokens->getPosition();
unsigned Position = StoredPosition;
FormatToken *Tok = FormatTok;
// Keep a stack of positions of lbrace tokens. We will
// update information about whether an lbrace starts a
// braced init list or a different block during the loop.
SmallVector<FormatToken *, 8> LBraceStack;
assert(Tok->Tok.is(tok::l_brace));
do {
// Get next none-comment token.
FormatToken *NextTok;
unsigned ReadTokens = 0;
do {
NextTok = Tokens->getNextToken();
++ReadTokens;
} while (NextTok->is(tok::comment));
switch (Tok->Tok.getKind()) {
case tok::l_brace:
LBraceStack.push_back(Tok);
break;
case tok::r_brace:
if (!LBraceStack.empty()) {
if (LBraceStack.back()->BlockKind == BK_Unknown) {
// If there is a comma, semicolon or right paren after the closing
// brace, we assume this is a braced initializer list. Note that
// regardless how we mark inner braces here, we will overwrite the
// BlockKind later if we parse a braced list (where all blocks inside
// are by default braced lists), or when we explicitly detect blocks
// (for example while parsing lambdas).
//
// We exclude + and - as they can be ObjC visibility modifiers.
if (NextTok->isOneOf(tok::comma, tok::semi, tok::r_paren,
tok::r_square, tok::l_brace, tok::colon) ||
(NextTok->isBinaryOperator() &&
!NextTok->isOneOf(tok::plus, tok::minus))) {
Tok->BlockKind = BK_BracedInit;
LBraceStack.back()->BlockKind = BK_BracedInit;
} else {
Tok->BlockKind = BK_Block;
LBraceStack.back()->BlockKind = BK_Block;
}
}
LBraceStack.pop_back();
}
break;
case tok::semi:
case tok::kw_if:
case tok::kw_while:
case tok::kw_for:
case tok::kw_switch:
case tok::kw_try:
if (!LBraceStack.empty())
LBraceStack.back()->BlockKind = BK_Block;
break;
default:
break;
}
Tok = NextTok;
Position += ReadTokens;
} while (Tok->Tok.isNot(tok::eof) && !LBraceStack.empty());
// Assume other blocks for all unclosed opening braces.
for (unsigned i = 0, e = LBraceStack.size(); i != e; ++i) {
if (LBraceStack[i]->BlockKind == BK_Unknown)
LBraceStack[i]->BlockKind = BK_Block;
}
FormatTok = Tokens->setPosition(StoredPosition);
}
void UnwrappedLineParser::parseBlock(bool MustBeDeclaration, bool AddLevel,
bool MunchSemi) {
assert(FormatTok->Tok.is(tok::l_brace) && "'{' expected");
unsigned InitialLevel = Line->Level;
nextToken();
addUnwrappedLine();
ScopedDeclarationState DeclarationState(*Line, DeclarationScopeStack,
MustBeDeclaration);
if (AddLevel)
++Line->Level;
parseLevel(/*HasOpeningBrace=*/true);
if (!FormatTok->Tok.is(tok::r_brace)) {
Line->Level = InitialLevel;
StructuralError = true;
return;
}
nextToken(); // Munch the closing brace.
if (MunchSemi && FormatTok->Tok.is(tok::semi))
nextToken();
Line->Level = InitialLevel;
}
void UnwrappedLineParser::parseChildBlock() {
FormatTok->BlockKind = BK_Block;
nextToken();
{
ScopedLineState LineState(*this);
ScopedDeclarationState DeclarationState(*Line, DeclarationScopeStack,
/*MustBeDeclaration=*/false);
Line->Level += 1;
parseLevel(/*HasOpeningBrace=*/true);
Line->Level -= 1;
}
nextToken();
}
void UnwrappedLineParser::parsePPDirective() {
assert(FormatTok->Tok.is(tok::hash) && "'#' expected");
ScopedMacroState MacroState(*Line, Tokens, FormatTok, StructuralError);
nextToken();
if (FormatTok->Tok.getIdentifierInfo() == NULL) {
parsePPUnknown();
return;
}
switch (FormatTok->Tok.getIdentifierInfo()->getPPKeywordID()) {
case tok::pp_define:
parsePPDefine();
return;
case tok::pp_if:
parsePPIf(/*IfDef=*/false);
break;
case tok::pp_ifdef:
case tok::pp_ifndef:
parsePPIf(/*IfDef=*/true);
break;
case tok::pp_else:
parsePPElse();
break;
case tok::pp_elif:
parsePPElIf();
break;
case tok::pp_endif:
parsePPEndIf();
break;
default:
parsePPUnknown();
break;
}
}
void UnwrappedLineParser::pushPPConditional() {
if (!PPStack.empty() && PPStack.back() == PP_Unreachable)
PPStack.push_back(PP_Unreachable);
else
PPStack.push_back(PP_Conditional);
}
void UnwrappedLineParser::parsePPIf(bool IfDef) {
++PPBranchLevel;
assert(PPBranchLevel >= 0 && PPBranchLevel <= (int)PPLevelBranchIndex.size());
if (PPBranchLevel == (int)PPLevelBranchIndex.size()) {
PPLevelBranchIndex.push_back(0);
PPLevelBranchCount.push_back(0);
}
PPChainBranchIndex.push(0);
nextToken();
bool IsLiteralFalse = (FormatTok->Tok.isLiteral() &&
StringRef(FormatTok->Tok.getLiteralData(),
FormatTok->Tok.getLength()) == "0") ||
FormatTok->Tok.is(tok::kw_false);
if ((!IfDef && IsLiteralFalse) || PPLevelBranchIndex[PPBranchLevel] > 0) {
PPStack.push_back(PP_Unreachable);
} else {
pushPPConditional();
}
parsePPUnknown();
}
void UnwrappedLineParser::parsePPElse() {
if (!PPStack.empty())
PPStack.pop_back();
assert(PPBranchLevel < (int)PPLevelBranchIndex.size());
if (!PPChainBranchIndex.empty())
++PPChainBranchIndex.top();
if (PPBranchLevel >= 0 && !PPChainBranchIndex.empty() &&
PPLevelBranchIndex[PPBranchLevel] != PPChainBranchIndex.top()) {
PPStack.push_back(PP_Unreachable);
} else {
pushPPConditional();
}
parsePPUnknown();
}
void UnwrappedLineParser::parsePPElIf() { parsePPElse(); }
void UnwrappedLineParser::parsePPEndIf() {
assert(PPBranchLevel < (int)PPLevelBranchIndex.size());
if (PPBranchLevel >= 0 && !PPChainBranchIndex.empty()) {
if (PPChainBranchIndex.top() + 1 > PPLevelBranchCount[PPBranchLevel]) {
PPLevelBranchCount[PPBranchLevel] = PPChainBranchIndex.top() + 1;
}
}
--PPBranchLevel;
if (!PPChainBranchIndex.empty())
PPChainBranchIndex.pop();
if (!PPStack.empty())
PPStack.pop_back();
parsePPUnknown();
}
void UnwrappedLineParser::parsePPDefine() {
nextToken();
if (FormatTok->Tok.getKind() != tok::identifier) {
parsePPUnknown();
return;
}
nextToken();
if (FormatTok->Tok.getKind() == tok::l_paren &&
FormatTok->WhitespaceRange.getBegin() ==
FormatTok->WhitespaceRange.getEnd()) {
parseParens();
}
addUnwrappedLine();
Line->Level = 1;
// Errors during a preprocessor directive can only affect the layout of the
// preprocessor directive, and thus we ignore them. An alternative approach
// would be to use the same approach we use on the file level (no
// re-indentation if there was a structural error) within the macro
// definition.
parseFile();
}
void UnwrappedLineParser::parsePPUnknown() {
do {
nextToken();
} while (!eof());
addUnwrappedLine();
}
// Here we blacklist certain tokens that are not usually the first token in an
// unwrapped line. This is used in attempt to distinguish macro calls without
// trailing semicolons from other constructs split to several lines.
bool tokenCanStartNewLine(clang::Token Tok) {
// Semicolon can be a null-statement, l_square can be a start of a macro or
// a C++11 attribute, but this doesn't seem to be common.
return Tok.isNot(tok::semi) && Tok.isNot(tok::l_brace) &&
Tok.isNot(tok::l_square) &&
// Tokens that can only be used as binary operators and a part of
// overloaded operator names.
Tok.isNot(tok::period) && Tok.isNot(tok::periodstar) &&
Tok.isNot(tok::arrow) && Tok.isNot(tok::arrowstar) &&
Tok.isNot(tok::less) && Tok.isNot(tok::greater) &&
Tok.isNot(tok::slash) && Tok.isNot(tok::percent) &&
Tok.isNot(tok::lessless) && Tok.isNot(tok::greatergreater) &&
Tok.isNot(tok::equal) && Tok.isNot(tok::plusequal) &&
Tok.isNot(tok::minusequal) && Tok.isNot(tok::starequal) &&
Tok.isNot(tok::slashequal) && Tok.isNot(tok::percentequal) &&
Tok.isNot(tok::ampequal) && Tok.isNot(tok::pipeequal) &&
Tok.isNot(tok::caretequal) && Tok.isNot(tok::greatergreaterequal) &&
Tok.isNot(tok::lesslessequal) &&
// Colon is used in labels, base class lists, initializer lists,
// range-based for loops, ternary operator, but should never be the
// first token in an unwrapped line.
Tok.isNot(tok::colon);
}
void UnwrappedLineParser::parseStructuralElement() {
assert(!FormatTok->Tok.is(tok::l_brace));
switch (FormatTok->Tok.getKind()) {
case tok::at:
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
parseBracedList();
break;
}
switch (FormatTok->Tok.getObjCKeywordID()) {
case tok::objc_public:
case tok::objc_protected:
case tok::objc_package:
case tok::objc_private:
return parseAccessSpecifier();
case tok::objc_interface:
case tok::objc_implementation:
return parseObjCInterfaceOrImplementation();
case tok::objc_protocol:
return parseObjCProtocol();
case tok::objc_end:
return; // Handled by the caller.
case tok::objc_optional:
case tok::objc_required:
nextToken();
addUnwrappedLine();
return;
default:
break;
}
break;
case tok::kw_namespace:
parseNamespace();
return;
case tok::kw_inline:
nextToken();
if (FormatTok->Tok.is(tok::kw_namespace)) {
parseNamespace();
return;
}
break;
case tok::kw_public:
case tok::kw_protected:
case tok::kw_private:
parseAccessSpecifier();
return;
case tok::kw_if:
parseIfThenElse();
return;
case tok::kw_for:
case tok::kw_while:
parseForOrWhileLoop();
return;
case tok::kw_do:
parseDoWhile();
return;
case tok::kw_switch:
parseSwitch();
return;
case tok::kw_default:
nextToken();
parseLabel();
return;
case tok::kw_case:
parseCaseLabel();
return;
case tok::kw_return:
parseReturn();
return;
case tok::kw_extern:
nextToken();
if (FormatTok->Tok.is(tok::string_literal)) {
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
parseBlock(/*MustBeDeclaration=*/true, /*AddLevel=*/false);
addUnwrappedLine();
return;
}
}
// In all other cases, parse the declaration.
break;
default:
break;
}
do {
switch (FormatTok->Tok.getKind()) {
case tok::at:
nextToken();
if (FormatTok->Tok.is(tok::l_brace))
parseBracedList();
break;
case tok::kw_enum:
parseEnum();
break;
case tok::kw_struct:
case tok::kw_union:
case tok::kw_class:
parseRecord();
// A record declaration or definition is always the start of a structural
// element.
break;
case tok::semi:
nextToken();
addUnwrappedLine();
return;
case tok::r_brace:
addUnwrappedLine();
return;
case tok::l_paren:
parseParens();
break;
case tok::caret:
nextToken();
if (FormatTok->is(tok::l_brace)) {
parseChildBlock();
}
break;
case tok::l_brace:
if (!tryToParseBracedList()) {
// A block outside of parentheses must be the last part of a
// structural element.
// FIXME: Figure out cases where this is not true, and add projections
// for them (the one we know is missing are lambdas).
if (Style.BreakBeforeBraces == FormatStyle::BS_Linux ||
Style.BreakBeforeBraces == FormatStyle::BS_Stroustrup ||
Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
addUnwrappedLine();
return;
}
// Otherwise this was a braced init list, and the structural
// element continues.
break;
case tok::identifier: {
StringRef Text = FormatTok->TokenText;
nextToken();
if (Line->Tokens.size() == 1) {
if (FormatTok->Tok.is(tok::colon)) {
parseLabel();
return;
}
// Recognize function-like macro usages without trailing semicolon.
if (FormatTok->Tok.is(tok::l_paren)) {
parseParens();
if (FormatTok->HasUnescapedNewline &&
tokenCanStartNewLine(FormatTok->Tok)) {
addUnwrappedLine();
return;
}
} else if (FormatTok->HasUnescapedNewline && Text.size() >= 5 &&
Text == Text.upper()) {
// Recognize free-standing macros like Q_OBJECT.
addUnwrappedLine();
return;
}
}
break;
}
case tok::equal:
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
parseBracedList();
}
break;
case tok::l_square:
tryToParseLambda();
break;
default:
nextToken();
break;
}
} while (!eof());
}
void UnwrappedLineParser::tryToParseLambda() {
// FIXME: This is a dirty way to access the previous token. Find a better
// solution.
if (!Line->Tokens.empty() &&
Line->Tokens.back().Tok->isOneOf(tok::identifier, tok::kw_operator)) {
nextToken();
return;
}
assert(FormatTok->is(tok::l_square));
FormatToken &LSquare = *FormatTok;
if (!tryToParseLambdaIntroducer())
return;
while (FormatTok->isNot(tok::l_brace)) {
switch (FormatTok->Tok.getKind()) {
case tok::l_brace:
break;
case tok::l_paren:
parseParens();
break;
case tok::identifier:
case tok::kw_mutable:
nextToken();
break;
default:
return;
}
}
LSquare.Type = TT_LambdaLSquare;
parseChildBlock();
}
bool UnwrappedLineParser::tryToParseLambdaIntroducer() {
nextToken();
if (FormatTok->is(tok::equal)) {
nextToken();
if (FormatTok->is(tok::r_square)) {
nextToken();
return true;
}
if (FormatTok->isNot(tok::comma))
return false;
nextToken();
} else if (FormatTok->is(tok::amp)) {
nextToken();
if (FormatTok->is(tok::r_square)) {
nextToken();
return true;
}
if (!FormatTok->isOneOf(tok::comma, tok::identifier)) {
return false;
}
if (FormatTok->is(tok::comma))
nextToken();
} else if (FormatTok->is(tok::r_square)) {
nextToken();
return true;
}
do {
if (FormatTok->is(tok::amp))
nextToken();
if (!FormatTok->isOneOf(tok::identifier, tok::kw_this))
return false;
nextToken();
if (FormatTok->is(tok::comma)) {
nextToken();
} else if (FormatTok->is(tok::r_square)) {
nextToken();
return true;
} else {
return false;
}
} while (!eof());
return false;
}
bool UnwrappedLineParser::tryToParseBracedList() {
if (FormatTok->BlockKind == BK_Unknown)
calculateBraceTypes();
assert(FormatTok->BlockKind != BK_Unknown);
if (FormatTok->BlockKind == BK_Block)
return false;
parseBracedList();
return true;
}
bool UnwrappedLineParser::parseBracedList(bool ContinueOnSemicolons) {
bool HasError = false;
nextToken();
// FIXME: Once we have an expression parser in the UnwrappedLineParser,
// replace this by using parseAssigmentExpression() inside.
do {
// FIXME: When we start to support lambdas, we'll want to parse them away
// here, otherwise our bail-out scenarios below break. The better solution
// might be to just implement a more or less complete expression parser.
switch (FormatTok->Tok.getKind()) {
case tok::caret:
nextToken();
if (FormatTok->is(tok::l_brace)) {
parseChildBlock();
}
break;
case tok::l_square:
tryToParseLambda();
break;
case tok::l_brace:
// Assume there are no blocks inside a braced init list apart
// from the ones we explicitly parse out (like lambdas).
FormatTok->BlockKind = BK_BracedInit;
parseBracedList();
break;
case tok::r_brace:
nextToken();
return !HasError;
case tok::semi:
HasError = true;
if (!ContinueOnSemicolons)
return !HasError;
nextToken();
break;
case tok::comma:
nextToken();
break;
default:
nextToken();
break;
}
} while (!eof());
return false;
}
void UnwrappedLineParser::parseReturn() {
nextToken();
do {
switch (FormatTok->Tok.getKind()) {
case tok::l_brace:
parseBracedList();
if (FormatTok->Tok.isNot(tok::semi)) {
// Assume missing ';'.
addUnwrappedLine();
return;
}
break;
case tok::l_paren:
parseParens();
break;
case tok::r_brace:
// Assume missing ';'.
addUnwrappedLine();
return;
case tok::semi:
nextToken();
addUnwrappedLine();
return;
case tok::l_square:
tryToParseLambda();
break;
default:
nextToken();
break;
}
} while (!eof());
}
void UnwrappedLineParser::parseParens() {
assert(FormatTok->Tok.is(tok::l_paren) && "'(' expected.");
nextToken();
do {
switch (FormatTok->Tok.getKind()) {
case tok::l_paren:
parseParens();
break;
case tok::r_paren:
nextToken();
return;
case tok::r_brace:
// A "}" inside parenthesis is an error if there wasn't a matching "{".
return;
case tok::l_square:
tryToParseLambda();
break;
case tok::l_brace: {
if (!tryToParseBracedList()) {
parseChildBlock();
}
break;
}
case tok::at:
nextToken();
if (FormatTok->Tok.is(tok::l_brace))
parseBracedList();
break;
default:
nextToken();
break;
}
} while (!eof());
}
void UnwrappedLineParser::parseIfThenElse() {
assert(FormatTok->Tok.is(tok::kw_if) && "'if' expected");
nextToken();
if (FormatTok->Tok.is(tok::l_paren))
parseParens();
bool NeedsUnwrappedLine = false;
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
else
NeedsUnwrappedLine = true;
} else {
addUnwrappedLine();
++Line->Level;
parseStructuralElement();
--Line->Level;
}
if (FormatTok->Tok.is(tok::kw_else)) {
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
addUnwrappedLine();
} else if (FormatTok->Tok.is(tok::kw_if)) {
parseIfThenElse();
} else {
addUnwrappedLine();
++Line->Level;
parseStructuralElement();
--Line->Level;
}
} else if (NeedsUnwrappedLine) {
addUnwrappedLine();
}
}
void UnwrappedLineParser::parseNamespace() {
assert(FormatTok->Tok.is(tok::kw_namespace) && "'namespace' expected");
nextToken();
if (FormatTok->Tok.is(tok::identifier))
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Linux ||
Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
bool AddLevel = Style.NamespaceIndentation == FormatStyle::NI_All ||
(Style.NamespaceIndentation == FormatStyle::NI_Inner &&
DeclarationScopeStack.size() > 1);
parseBlock(/*MustBeDeclaration=*/true, AddLevel);
// Munch the semicolon after a namespace. This is more common than one would
// think. Puttin the semicolon into its own line is very ugly.
if (FormatTok->Tok.is(tok::semi))
nextToken();
addUnwrappedLine();
}
// FIXME: Add error handling.
}
void UnwrappedLineParser::parseForOrWhileLoop() {
assert((FormatTok->Tok.is(tok::kw_for) || FormatTok->Tok.is(tok::kw_while)) &&
"'for' or 'while' expected");
nextToken();
if (FormatTok->Tok.is(tok::l_paren))
parseParens();
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
addUnwrappedLine();
} else {
addUnwrappedLine();
++Line->Level;
parseStructuralElement();
--Line->Level;
}
}
void UnwrappedLineParser::parseDoWhile() {
assert(FormatTok->Tok.is(tok::kw_do) && "'do' expected");
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
} else {
addUnwrappedLine();
++Line->Level;
parseStructuralElement();
--Line->Level;
}
// FIXME: Add error handling.
if (!FormatTok->Tok.is(tok::kw_while)) {
addUnwrappedLine();
return;
}
nextToken();
parseStructuralElement();
}
void UnwrappedLineParser::parseLabel() {
nextToken();
unsigned OldLineLevel = Line->Level;
if (Line->Level > 1 || (!Line->InPPDirective && Line->Level > 0))
--Line->Level;
if (CommentsBeforeNextToken.empty() && FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
if (FormatTok->Tok.is(tok::kw_break)) {
// "break;" after "}" on its own line only for BS_Allman
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseStructuralElement();
}
}
addUnwrappedLine();
Line->Level = OldLineLevel;
}
void UnwrappedLineParser::parseCaseLabel() {
assert(FormatTok->Tok.is(tok::kw_case) && "'case' expected");
// FIXME: fix handling of complex expressions here.
do {
nextToken();
} while (!eof() && !FormatTok->Tok.is(tok::colon));
parseLabel();
}
void UnwrappedLineParser::parseSwitch() {
assert(FormatTok->Tok.is(tok::kw_switch) && "'switch' expected");
nextToken();
if (FormatTok->Tok.is(tok::l_paren))
parseParens();
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
addUnwrappedLine();
} else {
addUnwrappedLine();
++Line->Level;
parseStructuralElement();
--Line->Level;
}
}
void UnwrappedLineParser::parseAccessSpecifier() {
nextToken();
// Otherwise, we don't know what it is, and we'd better keep the next token.
if (FormatTok->Tok.is(tok::colon))
nextToken();
addUnwrappedLine();
}
void UnwrappedLineParser::parseEnum() {
nextToken();
// Eat up enum class ...
if (FormatTok->Tok.is(tok::kw_class) ||
FormatTok->Tok.is(tok::kw_struct))
nextToken();
while (FormatTok->Tok.getIdentifierInfo() ||
FormatTok->isOneOf(tok::colon, tok::coloncolon)) {
nextToken();
// We can have macros or attributes in between 'enum' and the enum name.
if (FormatTok->Tok.is(tok::l_paren)) {
parseParens();
}
if (FormatTok->Tok.is(tok::identifier))
nextToken();
}
if (FormatTok->Tok.is(tok::l_brace)) {
FormatTok->BlockKind = BK_Block;
bool HasError = !parseBracedList(/*ContinueOnSemicolons=*/true);
if (HasError) {
if (FormatTok->is(tok::semi))
nextToken();
addUnwrappedLine();
}
}
// We fall through to parsing a structural element afterwards, so that in
// enum A {} n, m;
// "} n, m;" will end up in one unwrapped line.
}
void UnwrappedLineParser::parseRecord() {
nextToken();
if (FormatTok->Tok.is(tok::identifier) ||
FormatTok->Tok.is(tok::kw___attribute) ||
FormatTok->Tok.is(tok::kw___declspec) ||
FormatTok->Tok.is(tok::kw_alignas)) {
nextToken();
// We can have macros or attributes in between 'class' and the class name.
if (FormatTok->Tok.is(tok::l_paren)) {
parseParens();
}
// The actual identifier can be a nested name specifier, and in macros
// it is often token-pasted.
while (FormatTok->Tok.is(tok::identifier) ||
FormatTok->Tok.is(tok::coloncolon) ||
FormatTok->Tok.is(tok::hashhash))
nextToken();
// Note that parsing away template declarations here leads to incorrectly
// accepting function declarations as record declarations.
// In general, we cannot solve this problem. Consider:
// class A<int> B() {}
// which can be a function definition or a class definition when B() is a
// macro. If we find enough real-world cases where this is a problem, we
// can parse for the 'template' keyword in the beginning of the statement,
// and thus rule out the record production in case there is no template
// (this would still leave us with an ambiguity between template function
// and class declarations).
if (FormatTok->Tok.is(tok::colon) || FormatTok->Tok.is(tok::less)) {
while (!eof() && FormatTok->Tok.isNot(tok::l_brace)) {
if (FormatTok->Tok.is(tok::semi))
return;
nextToken();
}
}
}
if (FormatTok->Tok.is(tok::l_brace)) {
if (Style.BreakBeforeBraces == FormatStyle::BS_Linux ||
Style.BreakBeforeBraces == FormatStyle::BS_Allman)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/true, /*Addlevel=*/true,
/*MunchSemi=*/false);
}
// We fall through to parsing a structural element afterwards, so
// class A {} n, m;
// will end up in one unwrapped line.
}
void UnwrappedLineParser::parseObjCProtocolList() {
assert(FormatTok->Tok.is(tok::less) && "'<' expected.");
do
nextToken();
while (!eof() && FormatTok->Tok.isNot(tok::greater));
nextToken(); // Skip '>'.
}
void UnwrappedLineParser::parseObjCUntilAtEnd() {
do {
if (FormatTok->Tok.isObjCAtKeyword(tok::objc_end)) {
nextToken();
addUnwrappedLine();
break;
}
if (FormatTok->is(tok::l_brace)) {
parseBlock(/*MustBeDeclaration=*/false);
// In ObjC interfaces, nothing should be following the "}".
addUnwrappedLine();
} else {
parseStructuralElement();
}
} while (!eof());
}
void UnwrappedLineParser::parseObjCInterfaceOrImplementation() {
nextToken();
nextToken(); // interface name
// @interface can be followed by either a base class, or a category.
if (FormatTok->Tok.is(tok::colon)) {
nextToken();
nextToken(); // base class name
} else if (FormatTok->Tok.is(tok::l_paren))
// Skip category, if present.
parseParens();
if (FormatTok->Tok.is(tok::less))
parseObjCProtocolList();
// If instance variables are present, keep the '{' on the first line too.
if (FormatTok->Tok.is(tok::l_brace))
parseBlock(/*MustBeDeclaration=*/true);
// With instance variables, this puts '}' on its own line. Without instance
// variables, this ends the @interface line.
addUnwrappedLine();
parseObjCUntilAtEnd();
}
void UnwrappedLineParser::parseObjCProtocol() {
nextToken();
nextToken(); // protocol name
if (FormatTok->Tok.is(tok::less))
parseObjCProtocolList();
// Check for protocol declaration.
if (FormatTok->Tok.is(tok::semi)) {
nextToken();
return addUnwrappedLine();
}
addUnwrappedLine();
parseObjCUntilAtEnd();
}
LLVM_ATTRIBUTE_UNUSED static void printDebugInfo(const UnwrappedLine &Line,
StringRef Prefix = "") {
llvm::dbgs() << Prefix << "Line(" << Line.Level << ")"
<< (Line.InPPDirective ? " MACRO" : "") << ": ";
for (std::list<UnwrappedLineNode>::const_iterator I = Line.Tokens.begin(),
E = Line.Tokens.end();
I != E; ++I) {
llvm::dbgs() << I->Tok->Tok.getName() << "[" << I->Tok->Type << "] ";
}
for (std::list<UnwrappedLineNode>::const_iterator I = Line.Tokens.begin(),
E = Line.Tokens.end();
I != E; ++I) {
const UnwrappedLineNode &Node = *I;
for (SmallVectorImpl<UnwrappedLine>::const_iterator
I = Node.Children.begin(),
E = Node.Children.end();
I != E; ++I) {
printDebugInfo(*I, "\nChild: ");
}
}
llvm::dbgs() << "\n";
}
void UnwrappedLineParser::addUnwrappedLine() {
if (Line->Tokens.empty())
return;
DEBUG({
if (CurrentLines == &Lines)
printDebugInfo(*Line);
});
CurrentLines->push_back(*Line);
Line->Tokens.clear();
if (CurrentLines == &Lines && !PreprocessorDirectives.empty()) {
for (SmallVectorImpl<UnwrappedLine>::iterator
I = PreprocessorDirectives.begin(),
E = PreprocessorDirectives.end();
I != E; ++I) {
CurrentLines->push_back(*I);
}
PreprocessorDirectives.clear();
}
}
bool UnwrappedLineParser::eof() const { return FormatTok->Tok.is(tok::eof); }
void UnwrappedLineParser::flushComments(bool NewlineBeforeNext) {
bool JustComments = Line->Tokens.empty();
for (SmallVectorImpl<FormatToken *>::const_iterator
I = CommentsBeforeNextToken.begin(),
E = CommentsBeforeNextToken.end();
I != E; ++I) {
if ((*I)->NewlinesBefore && JustComments) {
addUnwrappedLine();
}
pushToken(*I);
}
if (NewlineBeforeNext && JustComments) {
addUnwrappedLine();
}
CommentsBeforeNextToken.clear();
}
void UnwrappedLineParser::nextToken() {
if (eof())
return;
flushComments(FormatTok->NewlinesBefore > 0);
pushToken(FormatTok);
readToken();
}
void UnwrappedLineParser::readToken() {
bool CommentsInCurrentLine = true;
do {
FormatTok = Tokens->getNextToken();
while (!Line->InPPDirective && FormatTok->Tok.is(tok::hash) &&
(FormatTok->HasUnescapedNewline || FormatTok->IsFirst)) {
// If there is an unfinished unwrapped line, we flush the preprocessor
// directives only after that unwrapped line was finished later.
bool SwitchToPreprocessorLines =
!Line->Tokens.empty() && CurrentLines == &Lines;
ScopedLineState BlockState(*this, SwitchToPreprocessorLines);
// Comments stored before the preprocessor directive need to be output
// before the preprocessor directive, at the same level as the
// preprocessor directive, as we consider them to apply to the directive.
flushComments(FormatTok->NewlinesBefore > 0);
parsePPDirective();
}
if (!PPStack.empty() && (PPStack.back() == PP_Unreachable) &&
!Line->InPPDirective) {
continue;
}
if (!FormatTok->Tok.is(tok::comment))
return;
if (FormatTok->NewlinesBefore > 0 || FormatTok->IsFirst) {
CommentsInCurrentLine = false;
}
if (CommentsInCurrentLine) {
pushToken(FormatTok);
} else {
CommentsBeforeNextToken.push_back(FormatTok);
}
} while (!eof());
}
void UnwrappedLineParser::pushToken(FormatToken *Tok) {
Line->Tokens.push_back(UnwrappedLineNode(Tok));
if (MustBreakBeforeNextToken) {
Line->Tokens.back().Tok->MustBreakBefore = true;
MustBreakBeforeNextToken = false;
}
}
} // end namespace format
} // end namespace clang