llvm-project/clang-tools-extra/clang-tidy/readability/ContainerContainsCheck.cpp

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5.9 KiB
C++

//===--- ContainerContainsCheck.cpp - clang-tidy --------------------------===//
//
// 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 "ContainerContainsCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace readability {
void ContainerContainsCheck::registerMatchers(MatchFinder *Finder) {
const auto SupportedContainers = hasType(
hasUnqualifiedDesugaredType(recordType(hasDeclaration(cxxRecordDecl(
hasAnyName("::std::set", "::std::unordered_set", "::std::map",
"::std::unordered_map", "::std::multiset",
"::std::unordered_multiset", "::std::multimap",
"::std::unordered_multimap"))))));
const auto CountCall =
cxxMemberCallExpr(on(SupportedContainers),
callee(cxxMethodDecl(hasName("count"))),
argumentCountIs(1))
.bind("call");
const auto FindCall =
cxxMemberCallExpr(on(SupportedContainers),
callee(cxxMethodDecl(hasName("find"))),
argumentCountIs(1))
.bind("call");
const auto EndCall = cxxMemberCallExpr(on(SupportedContainers),
callee(cxxMethodDecl(hasName("end"))),
argumentCountIs(0));
const auto Literal0 = integerLiteral(equals(0));
const auto Literal1 = integerLiteral(equals(1));
auto AddSimpleMatcher = [&](auto Matcher) {
Finder->addMatcher(
traverse(TK_IgnoreUnlessSpelledInSource, std::move(Matcher)), this);
};
// Find membership tests which use `count()`.
Finder->addMatcher(implicitCastExpr(hasImplicitDestinationType(booleanType()),
hasSourceExpression(CountCall))
.bind("positiveComparison"),
this);
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName("!="), hasRHS(Literal0))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal0), hasOperatorName("!="), hasRHS(CountCall))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName(">"), hasRHS(Literal0))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal0), hasOperatorName("<"), hasRHS(CountCall))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName(">="), hasRHS(Literal1))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal1), hasOperatorName("<="), hasRHS(CountCall))
.bind("positiveComparison"));
// Find inverted membership tests which use `count()`.
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName("=="), hasRHS(Literal0))
.bind("negativeComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal0), hasOperatorName("=="), hasRHS(CountCall))
.bind("negativeComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName("<="), hasRHS(Literal0))
.bind("negativeComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal0), hasOperatorName(">="), hasRHS(CountCall))
.bind("negativeComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(CountCall), hasOperatorName("<"), hasRHS(Literal1))
.bind("negativeComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(Literal1), hasOperatorName(">"), hasRHS(CountCall))
.bind("negativeComparison"));
// Find membership tests based on `find() == end()`.
AddSimpleMatcher(
binaryOperator(hasLHS(FindCall), hasOperatorName("!="), hasRHS(EndCall))
.bind("positiveComparison"));
AddSimpleMatcher(
binaryOperator(hasLHS(FindCall), hasOperatorName("=="), hasRHS(EndCall))
.bind("negativeComparison"));
}
void ContainerContainsCheck::check(const MatchFinder::MatchResult &Result) {
// Extract the information about the match
const auto *Call = Result.Nodes.getNodeAs<CXXMemberCallExpr>("call");
const auto *PositiveComparison =
Result.Nodes.getNodeAs<Expr>("positiveComparison");
const auto *NegativeComparison =
Result.Nodes.getNodeAs<Expr>("negativeComparison");
assert(
!PositiveComparison ||
!NegativeComparison &&
"only one of PositiveComparison or NegativeComparison should be set");
bool Negated = NegativeComparison != nullptr;
const auto *Comparison = Negated ? NegativeComparison : PositiveComparison;
// Diagnose the issue.
auto Diag =
diag(Call->getExprLoc(), "use 'contains' to check for membership");
// Don't fix it if it's in a macro invocation. Leave fixing it to the user.
SourceLocation FuncCallLoc = Comparison->getEndLoc();
if (!FuncCallLoc.isValid() || FuncCallLoc.isMacroID())
return;
// Create the fix it.
const auto *Member = cast<MemberExpr>(Call->getCallee());
Diag << FixItHint::CreateReplacement(
Member->getMemberNameInfo().getSourceRange(), "contains");
SourceLocation ComparisonBegin = Comparison->getSourceRange().getBegin();
SourceLocation ComparisonEnd = Comparison->getSourceRange().getEnd();
SourceLocation CallBegin = Call->getSourceRange().getBegin();
SourceLocation CallEnd = Call->getSourceRange().getEnd();
Diag << FixItHint::CreateReplacement(
CharSourceRange::getCharRange(ComparisonBegin, CallBegin),
Negated ? "!" : "");
Diag << FixItHint::CreateRemoval(CharSourceRange::getCharRange(
CallEnd.getLocWithOffset(1), ComparisonEnd.getLocWithOffset(1)));
}
} // namespace readability
} // namespace tidy
} // namespace clang