llvm-project/clang-tools-extra/clang-tidy/performance/FasterStringFindCheck.cpp

106 lines
3.5 KiB
C++

//===--- FasterStringFindCheck.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 "FasterStringFindCheck.h"
#include "../utils/OptionsUtils.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "llvm/ADT/Optional.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace performance {
namespace {
llvm::Optional<std::string> MakeCharacterLiteral(const StringLiteral *Literal) {
std::string Result;
{
llvm::raw_string_ostream OS(Result);
Literal->outputString(OS);
}
// Now replace the " with '.
auto pos = Result.find_first_of('"');
if (pos == Result.npos)
return llvm::None;
Result[pos] = '\'';
pos = Result.find_last_of('"');
if (pos == Result.npos)
return llvm::None;
Result[pos] = '\'';
return Result;
}
AST_MATCHER_FUNCTION(ast_matchers::internal::Matcher<Expr>,
hasSubstitutedType) {
return hasType(qualType(anyOf(substTemplateTypeParmType(),
hasDescendant(substTemplateTypeParmType()))));
}
} // namespace
FasterStringFindCheck::FasterStringFindCheck(StringRef Name,
ClangTidyContext *Context)
: ClangTidyCheck(Name, Context),
StringLikeClasses(utils::options::parseStringList(
Options.get("StringLikeClasses", "std::basic_string"))) {}
void FasterStringFindCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
Options.store(Opts, "StringLikeClasses",
utils::options::serializeStringList(StringLikeClasses));
}
void FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus)
return;
const auto SingleChar =
expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));
const auto StringFindFunctions =
hasAnyName("find", "rfind", "find_first_of", "find_first_not_of",
"find_last_of", "find_last_not_of");
Finder->addMatcher(
cxxMemberCallExpr(
callee(functionDecl(StringFindFunctions).bind("func")),
anyOf(argumentCountIs(1), argumentCountIs(2)),
hasArgument(0, SingleChar),
on(expr(
hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
recordDecl(hasAnyName(SmallVector<StringRef, 4>(
StringLikeClasses.begin(), StringLikeClasses.end()))))))),
unless(hasSubstitutedType())))),
this);
}
void FasterStringFindCheck::check(const MatchFinder::MatchResult &Result) {
const auto *Literal = Result.Nodes.getNodeAs<StringLiteral>("literal");
const auto *FindFunc = Result.Nodes.getNodeAs<FunctionDecl>("func");
auto Replacement = MakeCharacterLiteral(Literal);
if (!Replacement)
return;
diag(Literal->getBeginLoc(), "%0 called with a string literal consisting of "
"a single character; consider using the more "
"effective overload accepting a character")
<< FindFunc
<< FixItHint::CreateReplacement(
CharSourceRange::getTokenRange(Literal->getBeginLoc(),
Literal->getEndLoc()),
*Replacement);
}
} // namespace performance
} // namespace tidy
} // namespace clang