clang-tools 19.0.0git
FasterStringFindCheck.cpp
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1//===--- FasterStringFindCheck.cpp - clang-tidy----------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
10#include "../utils/OptionsUtils.h"
11#include "clang/AST/ASTContext.h"
12#include "clang/ASTMatchers/ASTMatchFinder.h"
13#include "llvm/Support/raw_ostream.h"
14#include <optional>
15
16using namespace clang::ast_matchers;
17
19
20namespace {
21
22std::optional<std::string> makeCharacterLiteral(const StringLiteral *Literal) {
23 std::string Result;
24 {
25 llvm::raw_string_ostream OS(Result);
26 Literal->outputString(OS);
27 }
28 // Now replace the " with '.
29 auto OpenPos = Result.find_first_of('"');
30 if (OpenPos == std::string::npos)
31 return std::nullopt;
32 Result[OpenPos] = '\'';
33
34 auto ClosePos = Result.find_last_of('"');
35 if (ClosePos == std::string::npos)
36 return std::nullopt;
37 Result[ClosePos] = '\'';
38
39 // "'" is OK, but ''' is not, so add a backslash
40 if ((ClosePos - OpenPos) == 2 && Result[OpenPos + 1] == '\'')
41 Result.replace(OpenPos + 1, 1, "\\'");
42
43 return Result;
44}
45
46AST_MATCHER_FUNCTION(ast_matchers::internal::Matcher<Expr>,
47 hasSubstitutedType) {
48 return hasType(qualType(anyOf(substTemplateTypeParmType(),
49 hasDescendant(substTemplateTypeParmType()))));
50}
51
52} // namespace
53
55 ClangTidyContext *Context)
56 : ClangTidyCheck(Name, Context),
57 StringLikeClasses(utils::options::parseStringList(
58 Options.get("StringLikeClasses",
59 "::std::basic_string;::std::basic_string_view"))) {}
60
62 Options.store(Opts, "StringLikeClasses",
63 utils::options::serializeStringList(StringLikeClasses));
64}
65
66void FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
67 const auto SingleChar =
68 expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));
69 const auto StringFindFunctions =
70 hasAnyName("find", "rfind", "find_first_of", "find_first_not_of",
71 "find_last_of", "find_last_not_of");
72
73 Finder->addMatcher(
74 cxxMemberCallExpr(
75 callee(functionDecl(StringFindFunctions).bind("func")),
76 anyOf(argumentCountIs(1), argumentCountIs(2)),
77 hasArgument(0, SingleChar),
78 on(expr(hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
79 recordDecl(hasAnyName(StringLikeClasses)))))),
80 unless(hasSubstitutedType())))),
81 this);
82}
83
84void FasterStringFindCheck::check(const MatchFinder::MatchResult &Result) {
85 const auto *Literal = Result.Nodes.getNodeAs<StringLiteral>("literal");
86 const auto *FindFunc = Result.Nodes.getNodeAs<FunctionDecl>("func");
87
88 auto Replacement = makeCharacterLiteral(Literal);
89 if (!Replacement)
90 return;
91
92 diag(Literal->getBeginLoc(), "%0 called with a string literal consisting of "
93 "a single character; consider using the more "
94 "effective overload accepting a character")
95 << FindFunc
96 << FixItHint::CreateReplacement(
97 CharSourceRange::getTokenRange(Literal->getBeginLoc(),
98 Literal->getEndLoc()),
99 *Replacement);
100}
101
102} // namespace clang::tidy::performance
llvm::SmallString< 256U > Name
llvm::raw_string_ostream OS
Definition: TraceTests.cpp:160
void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName, StringRef Value) const
Stores an option with the check-local name LocalName with string value Value to Options.
Base class for all clang-tidy checks.
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check's name.
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
FasterStringFindCheck(StringRef Name, ClangTidyContext *Context)
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...
AST_MATCHER_FUNCTION(ast_matchers::internal::Matcher< FunctionDecl >, DurationConversionFunction)
std::string serializeStringList(ArrayRef< StringRef > Strings)
Serialize a sequence of names that can be parsed by parseStringList.
llvm::StringMap< ClangTidyValue > OptionMap