llvm-project/clang/lib/Format/TokenAnnotator.h

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//===--- TokenAnnotator.h - Format C++ code ---------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file implements a token annotator, i.e. creates
/// \c AnnotatedTokens out of \c FormatTokens with required extra information.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
#define LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
#include "UnwrappedLineParser.h"
#include "clang/Format/Format.h"
#include <string>
namespace clang {
class SourceManager;
namespace format {
enum LineType {
LT_Invalid,
LT_ImportStatement,
LT_ObjCDecl, // An @interface, @implementation, or @protocol line.
LT_ObjCMethodDecl,
LT_ObjCProperty, // An @property line.
LT_Other,
LT_PreprocessorDirective,
LT_VirtualFunctionDecl
};
class AnnotatedLine {
public:
AnnotatedLine(const UnwrappedLine &Line)
: First(Line.Tokens.front().Tok), Level(Line.Level),
InPPDirective(Line.InPPDirective),
MustBeDeclaration(Line.MustBeDeclaration), MightBeFunctionDecl(false),
IsMultiVariableDeclStmt(false), Affected(false),
LeadingEmptyLinesAffected(false), ChildrenAffected(false) {
assert(!Line.Tokens.empty());
// Calculate Next and Previous for all tokens. Note that we must overwrite
// Next and Previous for every token, as previous formatting runs might have
// left them in a different state.
First->Previous = nullptr;
FormatToken *Current = First;
for (std::list<UnwrappedLineNode>::const_iterator I = ++Line.Tokens.begin(),
E = Line.Tokens.end();
I != E; ++I) {
const UnwrappedLineNode &Node = *I;
Current->Next = I->Tok;
I->Tok->Previous = Current;
Current = Current->Next;
Current->Children.clear();
for (const auto &Child : Node.Children) {
Children.push_back(new AnnotatedLine(Child));
Current->Children.push_back(Children.back());
}
}
Last = Current;
Last->Next = nullptr;
}
~AnnotatedLine() {
for (unsigned i = 0, e = Children.size(); i != e; ++i) {
delete Children[i];
}
FormatToken *Current = First;
while (Current) {
Current->Children.clear();
Current->Role.reset();
Current = Current->Next;
}
}
/// \c true if this line starts with the given tokens in order, ignoring
/// comments.
template <typename... Ts> bool startsWith(Ts... Tokens) const {
return startsWithInternal(First, Tokens...);
}
/// \c true if this line ends with the given tokens in reversed order,
/// ignoring comments.
/// For example, given tokens [T1, T2, T3, ...], the function returns true if
/// this line is like "... T3 T2 T1".
template <typename... Ts> bool endsWith(Ts... Tokens) const {
return endsWithInternal(Last, Tokens...);
}
/// \c true if this line looks like a function definition instead of a
/// function declaration. Asserts MightBeFunctionDecl.
bool mightBeFunctionDefinition() const {
assert(MightBeFunctionDecl);
// FIXME: Line.Last points to other characters than tok::semi
// and tok::lbrace.
return !Last->isOneOf(tok::semi, tok::comment);
}
FormatToken *First;
FormatToken *Last;
SmallVector<AnnotatedLine *, 0> Children;
LineType Type;
unsigned Level;
bool InPPDirective;
bool MustBeDeclaration;
bool MightBeFunctionDecl;
bool IsMultiVariableDeclStmt;
/// \c True if this line should be formatted, i.e. intersects directly or
/// indirectly with one of the input ranges.
bool Affected;
/// \c True if the leading empty lines of this line intersect with one of the
/// input ranges.
bool LeadingEmptyLinesAffected;
/// \c True if a one of this line's children intersects with an input range.
bool ChildrenAffected;
private:
// Disallow copying.
AnnotatedLine(const AnnotatedLine &) = delete;
void operator=(const AnnotatedLine &) = delete;
template <typename A, typename... Ts>
bool startsWithInternal(const FormatToken *Tok, A K1) const {
// Even though we skip comments in the outer `startWithInternal` function,
// this loop is still necessary if it is invoked by the public interface
// `startsWith`.
while (Tok && Tok->is(tok::comment))
Tok = Tok->Next;
return Tok && Tok->is(K1);
}
template <typename A, typename... Ts>
bool startsWithInternal(const FormatToken *Tok, A K1, Ts... Tokens) const {
// Skip comments before calling `startsWithInternal(Tok, K1)` so that the
// second call to `startsWithInternal` takes the correct `Tok->Next`, which
// should be the next token of the token checked in the first call.
while (Tok && Tok->is(tok::comment))
Tok = Tok->Next;
return Tok && startsWithInternal(Tok, K1) &&
startsWithInternal(Tok->Next, Tokens...);
}
template <typename A, typename... Ts>
bool endsWithInternal(const FormatToken *Tok, A K1) const {
// See the comments above in `startsWithInternal(Tok, K1)`.
while (Tok && Tok->is(tok::comment))
Tok = Tok->Previous;
return Tok && Tok->is(K1);
}
template <typename A, typename... Ts>
bool endsWithInternal(const FormatToken *Tok, A K1, Ts... Tokens) const {
// See the comments above in `startsWithInternal(Tok, K1, Tokens)`.
while (Tok && Tok->is(tok::comment))
Tok = Tok->Previous;
return Tok && endsWithInternal(Tok, K1) &&
endsWithInternal(Tok->Previous, Tokens...);
}
};
/// \brief Determines extra information about the tokens comprising an
/// \c UnwrappedLine.
class TokenAnnotator {
public:
TokenAnnotator(const FormatStyle &Style, const AdditionalKeywords &Keywords)
: Style(Style), Keywords(Keywords) {}
/// \brief Adapts the indent levels of comment lines to the indent of the
/// subsequent line.
// FIXME: Can/should this be done in the UnwrappedLineParser?
void setCommentLineLevels(SmallVectorImpl<AnnotatedLine *> &Lines);
void annotate(AnnotatedLine &Line);
void calculateFormattingInformation(AnnotatedLine &Line);
private:
/// \brief Calculate the penalty for splitting before \c Tok.
unsigned splitPenalty(const AnnotatedLine &Line, const FormatToken &Tok,
bool InFunctionDecl);
bool spaceRequiredBetween(const AnnotatedLine &Line, const FormatToken &Left,
const FormatToken &Right);
bool spaceRequiredBefore(const AnnotatedLine &Line, const FormatToken &Tok);
bool mustBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
bool canBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
bool mustBreakForReturnType(const AnnotatedLine &Line) const;
void printDebugInfo(const AnnotatedLine &Line);
void calculateUnbreakableTailLengths(AnnotatedLine &Line);
const FormatStyle &Style;
const AdditionalKeywords &Keywords;
};
} // end namespace format
} // end namespace clang
#endif