15 #include "clang/Lex/Lexer.h"
19 using namespace ast_matchers;
24 StringRef getText(
const ast_matchers::MatchFinder::MatchResult &
Result,
26 return Lexer::getSourceText(
27 CharSourceRange::getTokenRange(Node.getSourceRange()),
28 *Result.SourceManager, Result.Context->getLangOpts());
34 bool needParensAfterUnaryOperator(
const Expr &ExprNode) {
35 if (isa<clang::BinaryOperator>(&ExprNode) ||
36 isa<clang::ConditionalOperator>(&ExprNode)) {
39 if (
const auto *Op = dyn_cast<CXXOperatorCallExpr>(&ExprNode)) {
40 return Op->getNumArgs() == 2 && Op->getOperator() != OO_PlusPlus &&
41 Op->getOperator() != OO_MinusMinus && Op->getOperator() != OO_Call &&
42 Op->getOperator() != OO_Subscript;
50 formatDereference(
const ast_matchers::MatchFinder::MatchResult &Result,
51 const Expr &ExprNode) {
52 if (
const auto *Op = dyn_cast<clang::UnaryOperator>(&ExprNode)) {
53 if (Op->getOpcode() == UO_AddrOf) {
55 return getText(Result, *Op->getSubExpr()->IgnoreParens());
58 StringRef Text = getText(Result, ExprNode);
62 if (needParensAfterUnaryOperator(ExprNode)) {
63 return (llvm::Twine(
"*(") + Text +
")").str();
65 return (llvm::Twine(
"*") + Text).str();
68 const char StringConstructor[] =
69 "::std::basic_string<char, std::char_traits<char>, std::allocator<char> >"
72 const char StringCStrMethod[] =
73 "::std::basic_string<char, std::char_traits<char>, std::allocator<char> >"
79 namespace readability {
81 void RedundantStringCStrCheck::registerMatchers(
82 ast_matchers::MatchFinder *
Finder) {
85 if (!getLangOpts().CPlusPlus)
90 hasDeclaration(cxxMethodDecl(hasName(StringConstructor))),
96 hasArgument(0, cxxMemberCallExpr(
97 callee(memberExpr().bind(
"member")),
98 callee(cxxMethodDecl(hasName(StringCStrMethod))),
99 on(expr().bind(
"arg")))
103 hasArgument(1, cxxDefaultArgExpr())),
112 cxxMethodDecl(anyOf(hasName(
"::llvm::StringRef::StringRef"),
113 hasName(
"::llvm::Twine::Twine")))),
120 hasArgument(0, cxxMemberCallExpr(
121 callee(memberExpr().bind(
"member")),
122 callee(cxxMethodDecl(hasName(StringCStrMethod))),
123 on(expr().bind(
"arg")))
128 void RedundantStringCStrCheck::check(
const MatchFinder::MatchResult &Result) {
129 const auto *Call = Result.Nodes.getStmtAs<CallExpr>(
"call");
130 const auto *Arg = Result.Nodes.getStmtAs<Expr>(
"arg");
131 bool Arrow = Result.Nodes.getStmtAs<MemberExpr>(
"member")->isArrow();
134 std::string ArgText =
135 Arrow ? formatDereference(Result, *Arg) : getText(Result, *Arg).str();
139 diag(Call->getLocStart(),
"redundant call to `c_str()`")
140 << FixItHint::CreateReplacement(Call->getSourceRange(), ArgText);
std::unique_ptr< ast_matchers::MatchFinder > Finder