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

78 lines
2.7 KiB
C++

//===--- ExplicitMakePairCheck.cpp - clang-tidy -----------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "ExplicitMakePairCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/ASTMatchers/ASTMatchers.h"
using namespace clang::ast_matchers;
namespace clang {
namespace {
AST_MATCHER(DeclRefExpr, hasExplicitTemplateArgs) {
return Node.hasExplicitTemplateArgs();
}
} // namespace
namespace tidy {
namespace google {
namespace build {
void ExplicitMakePairCheck::registerMatchers(
ast_matchers::MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus)
return;
// Look for std::make_pair with explicit template args. Ignore calls in
// templates.
Finder->addMatcher(
callExpr(unless(isInTemplateInstantiation()),
callee(expr(ignoringParenImpCasts(
declRefExpr(hasExplicitTemplateArgs(),
to(functionDecl(hasName("::std::make_pair"))))
.bind("declref")))))
.bind("call"),
this);
}
void ExplicitMakePairCheck::check(const MatchFinder::MatchResult &Result) {
const auto *Call = Result.Nodes.getNodeAs<CallExpr>("call");
const auto *DeclRef = Result.Nodes.getNodeAs<DeclRefExpr>("declref");
// Sanity check: The use might have overriden ::std::make_pair.
if (Call->getNumArgs() != 2)
return;
const Expr *Arg0 = Call->getArg(0)->IgnoreParenImpCasts();
const Expr *Arg1 = Call->getArg(1)->IgnoreParenImpCasts();
// If types don't match, we suggest replacing with std::pair and explicit
// template arguments. Otherwise just remove the template arguments from
// make_pair.
if (Arg0->getType() != Call->getArg(0)->getType() ||
Arg1->getType() != Call->getArg(1)->getType()) {
diag(Call->getBeginLoc(), "for C++11-compatibility, use pair directly")
<< FixItHint::CreateReplacement(
SourceRange(DeclRef->getBeginLoc(), DeclRef->getLAngleLoc()),
"std::pair<");
} else {
diag(Call->getBeginLoc(),
"for C++11-compatibility, omit template arguments from make_pair")
<< FixItHint::CreateRemoval(
SourceRange(DeclRef->getLAngleLoc(), DeclRef->getRAngleLoc()));
}
}
} // namespace build
} // namespace google
} // namespace tidy
} // namespace clang