llvm-project/clang-tools-extra/clang-tidy/google/ExplicitConstructorCheck.cpp

86 lines
3.1 KiB
C++

//===--- ExplicitConstructorCheck.cpp - clang-tidy ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "ExplicitConstructorCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/ASTMatchers/ASTMatchers.h"
#include "clang/Lex/Lexer.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
void ExplicitConstructorCheck::registerMatchers(MatchFinder *Finder) {
Finder->addMatcher(constructorDecl().bind("ctor"), this);
}
// Looks for the token matching the predicate and returns the range of the found
// token including trailing whitespace.
SourceRange FindToken(const SourceManager &Sources, LangOptions LangOpts,
SourceLocation StartLoc, SourceLocation EndLoc,
bool (*Pred)(const Token &)) {
if (StartLoc.isMacroID() || EndLoc.isMacroID())
return SourceRange();
FileID File = Sources.getFileID(Sources.getSpellingLoc(StartLoc));
StringRef Buf = Sources.getBufferData(File);
const char *StartChar = Sources.getCharacterData(StartLoc);
Lexer Lex(StartLoc, LangOpts, StartChar, StartChar, Buf.end());
Lex.SetCommentRetentionState(true);
Token Tok;
do {
Lex.LexFromRawLexer(Tok);
if (Pred(Tok)) {
Token NextTok;
Lex.LexFromRawLexer(NextTok);
return SourceRange(Tok.getLocation(), NextTok.getLocation());
}
} while (Tok.isNot(tok::eof) && Tok.getLocation() < EndLoc);
return SourceRange();
}
void ExplicitConstructorCheck::check(const MatchFinder::MatchResult &Result) {
const CXXConstructorDecl *Ctor =
Result.Nodes.getNodeAs<CXXConstructorDecl>("ctor");
// Do not be confused: isExplicit means 'explicit' keyword is present,
// isImplicit means that it's a compiler-generated constructor.
if (Ctor->isOutOfLine() || Ctor->isImplicit() || Ctor->isDeleted())
return;
if (Ctor->isExplicit() && Ctor->isCopyOrMoveConstructor()) {
auto isKWExplicit = [](const Token &Tok) {
return Tok.is(tok::raw_identifier) &&
Tok.getRawIdentifier() == "explicit";
};
SourceRange ExplicitTokenRange =
FindToken(*Result.SourceManager, Result.Context->getLangOpts(),
Ctor->getOuterLocStart(), Ctor->getLocEnd(), isKWExplicit);
DiagnosticBuilder Diag =
diag(Ctor->getLocation(), "%0 constructor declared explicit.")
<< (Ctor->isMoveConstructor() ? "Move" : "Copy");
if (ExplicitTokenRange.isValid()) {
Diag << FixItHint::CreateRemoval(
CharSourceRange::getCharRange(ExplicitTokenRange));
}
}
if (Ctor->isExplicit() || Ctor->isCopyOrMoveConstructor() ||
Ctor->getNumParams() == 0 || Ctor->getMinRequiredArguments() > 1)
return;
SourceLocation Loc = Ctor->getLocation();
diag(Loc, "Single-argument constructors must be explicit")
<< FixItHint::CreateInsertion(Loc, "explicit ");
}
} // namespace tidy
} // namespace clang