clang-tools 6.0.0

FasterStringFindCheck.cpp
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1 //===--- FasterStringFindCheck.cpp - clang-tidy----------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "FasterStringFindCheck.h"
11 #include "../utils/OptionsUtils.h"
12 #include "clang/AST/ASTContext.h"
13 #include "clang/ASTMatchers/ASTMatchFinder.h"
14 #include "llvm/ADT/Optional.h"
15 #include "llvm/Support/raw_ostream.h"
16
17 using namespace clang::ast_matchers;
18
19 namespace clang {
20 namespace tidy {
21 namespace performance {
22
23 namespace {
24
25 llvm::Optional<std::string> MakeCharacterLiteral(const StringLiteral *Literal) {
26 std::string Result;
27 {
28 llvm::raw_string_ostream OS(Result);
29 Literal->outputString(OS);
30 }
31 // Now replace the " with '.
32 auto pos = Result.find_first_of('"');
33 if (pos == Result.npos)
34 return llvm::None;
35 Result[pos] = '\'';
36 pos = Result.find_last_of('"');
37 if (pos == Result.npos)
38 return llvm::None;
39 Result[pos] = '\'';
40 return Result;
41 }
42
43 AST_MATCHER_FUNCTION(ast_matchers::internal::Matcher<Expr>,
44 hasSubstitutedType) {
45 return hasType(qualType(anyOf(substTemplateTypeParmType(),
46 hasDescendant(substTemplateTypeParmType()))));
47 }
48
49 } // namespace
50
51 FasterStringFindCheck::FasterStringFindCheck(StringRef Name,
52 ClangTidyContext *Context)
53 : ClangTidyCheck(Name, Context),
54 StringLikeClasses(utils::options::parseStringList(
55 Options.get("StringLikeClasses", "std::basic_string"))) {}
56
57 void FasterStringFindCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
58 Options.store(Opts, "StringLikeClasses",
59 utils::options::serializeStringList(StringLikeClasses));
60 }
61
62 void FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
63 if (!getLangOpts().CPlusPlus)
64 return;
65
66 const auto SingleChar =
67 expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));
68 const auto StringFindFunctions =
69 hasAnyName("find", "rfind", "find_first_of", "find_first_not_of",
70 "find_last_of", "find_last_not_of");
71
72 Finder->addMatcher(
73 cxxMemberCallExpr(
74 callee(functionDecl(StringFindFunctions).bind("func")),
75 anyOf(argumentCountIs(1), argumentCountIs(2)),
76 hasArgument(0, SingleChar),
77 on(expr(
78 hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
79 recordDecl(hasAnyName(SmallVector<StringRef, 4>(
80 StringLikeClasses.begin(), StringLikeClasses.end()))))))),
81 unless(hasSubstitutedType())))),
82 this);
83 }
84
85 void FasterStringFindCheck::check(const MatchFinder::MatchResult &Result) {
86 const auto *Literal = Result.Nodes.getNodeAs<StringLiteral>("literal");
87 const auto *FindFunc = Result.Nodes.getNodeAs<FunctionDecl>("func");
88
89 auto Replacement = MakeCharacterLiteral(Literal);
90 if (!Replacement)
91 return;
92
93 diag(Literal->getLocStart(), "%0 called with a string literal consisting of "
94 "a single character; consider using the more "
95 "effective overload accepting a character")
96 << FindFunc << FixItHint::CreateReplacement(
97 CharSourceRange::getTokenRange(Literal->getLocStart(),
98 Literal->getLocEnd()),
99 *Replacement);
100 }
101
102 } // namespace performance
103 } // namespace tidy
104 } // namespace clang
clang::ast_matchers
Definition: ClangTidyDiagnosticConsumer.h:27
clang::tidy::performance::FasterStringFindCheck::storeOptions
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...
Definition: FasterStringFindCheck.cpp:57
clang::tidy::OptionsView::store
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.
Definition: ClangTidy.cpp:449
clang::tidy::utils::options::serializeStringList
std::string serializeStringList(ArrayRef< std::string > Strings)
Serialize a sequence of names that can be parsed by parseStringList.
Definition: OptionsUtils.cpp:31
Name
StringHandle Name
Definition: PreprocessorTracker.cpp:525
clang::tidy::ClangTidyCheck::getLangOpts
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:187
clang::tidy::performance::FasterStringFindCheck::check
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
Definition: FasterStringFindCheck.cpp:85
clang::tidy::ClangTidyCheck
Base class for all clang-tidy checks.
Definition: ClangTidy.h:127
FasterStringFindCheck.h
clang::tidy::utils::options::parseStringList
std::vector< std::string > parseStringList(StringRef Option)
Parse a semicolon separated list of strings.
Definition: OptionsUtils.cpp:19
clang::tidy::matchers::AST_MATCHER_FUNCTION
AST_MATCHER_FUNCTION(ast_matchers::TypeMatcher, isReferenceToConst)
Definition: Matchers.h:46
clang::tidy::ClangTidyCheck::Options
OptionsView Options
Definition: ClangTidy.h:183
clang::tidy::ClangTidyOptions::OptionMap
std::map< std::string, std::string > OptionMap
Definition: ClangTidyOptions.h:99
clang::tidy::performance::FasterStringFindCheck::registerMatchers
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
Definition: FasterStringFindCheck.cpp:62
clang
Definition: AndroidTidyModule.cpp:28
clang::tidy::ClangTidyContext
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
Definition: ClangTidyDiagnosticConsumer.h:104
clang::tidy::ClangTidyCheck::diag
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check&#39;s name.
Definition: ClangTidy.cpp:416