Author: alexfh Date: Thu Feb 25 17:57:23 2016 New Revision: 261939 URL: http://llvm.org/viewvc/llvm-project?rev=261939&view=rev Log: Add a new check, readability-redundant-string-init, that checks unnecessary string initializations.
Reviewers: hokein, alexfh Subscribers: cfe-commits Patch by Shuai Wang! Differential Revision: http://reviews.llvm.org/D17586 Added: clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.cpp clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.h clang-tools-extra/trunk/docs/clang-tidy/checks/readability-redundant-string-init.rst clang-tools-extra/trunk/test/clang-tidy/readability-redundant-string-init.cpp Modified: clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.cpp clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.h clang-tools-extra/trunk/clang-tidy/readability/CMakeLists.txt clang-tools-extra/trunk/clang-tidy/readability/ReadabilityTidyModule.cpp clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Modified: clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.cpp?rev=261939&r1=261938&r2=261939&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.cpp (original) +++ clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.cpp Thu Feb 25 17:57:23 2016 @@ -338,10 +338,9 @@ void ClangTidyDiagnosticConsumer::Handle Errors.push_back(ClangTidyError(CheckName, Level, IsWarningAsError)); } - // FIXME: Provide correct LangOptions for each file. - LangOptions LangOpts; ClangTidyDiagnosticRenderer Converter( - LangOpts, &Context.DiagEngine->getDiagnosticOptions(), Errors.back()); + Context.getLangOpts(), &Context.DiagEngine->getDiagnosticOptions(), + Errors.back()); SmallString<100> Message; Info.FormatDiagnostic(Message); SourceManager *Sources = nullptr; Modified: clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.h URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.h?rev=261939&r1=261938&r2=261939&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.h (original) +++ clang-tools-extra/trunk/clang-tidy/ClangTidyDiagnosticConsumer.h Thu Feb 25 17:57:23 2016 @@ -151,7 +151,7 @@ public: void setASTContext(ASTContext *Context); /// \brief Gets the language options from the AST context. - LangOptions getLangOpts() const { return LangOpts; } + const LangOptions &getLangOpts() const { return LangOpts; } /// \brief Returns the name of the clang-tidy check which produced this /// diagnostic ID. Modified: clang-tools-extra/trunk/clang-tidy/readability/CMakeLists.txt URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/readability/CMakeLists.txt?rev=261939&r1=261938&r2=261939&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/readability/CMakeLists.txt (original) +++ clang-tools-extra/trunk/clang-tidy/readability/CMakeLists.txt Thu Feb 25 17:57:23 2016 @@ -14,6 +14,7 @@ add_clang_library(clangTidyReadabilityMo RedundantControlFlowCheck.cpp RedundantStringCStrCheck.cpp RedundantSmartptrGetCheck.cpp + RedundantStringInitCheck.cpp SimplifyBooleanExprCheck.cpp UniqueptrDeleteReleaseCheck.cpp Modified: clang-tools-extra/trunk/clang-tidy/readability/ReadabilityTidyModule.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/readability/ReadabilityTidyModule.cpp?rev=261939&r1=261938&r2=261939&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/readability/ReadabilityTidyModule.cpp (original) +++ clang-tools-extra/trunk/clang-tidy/readability/ReadabilityTidyModule.cpp Thu Feb 25 17:57:23 2016 @@ -21,6 +21,7 @@ #include "RedundantControlFlowCheck.h" #include "RedundantSmartptrGetCheck.h" #include "RedundantStringCStrCheck.h" +#include "RedundantStringInitCheck.h" #include "SimplifyBooleanExprCheck.h" #include "UniqueptrDeleteReleaseCheck.h" @@ -53,6 +54,8 @@ public: "readability-redundant-smartptr-get"); CheckFactories.registerCheck<RedundantStringCStrCheck>( "readability-redundant-string-cstr"); + CheckFactories.registerCheck<RedundantStringInitCheck>( + "readability-redundant-string-init"); CheckFactories.registerCheck<SimplifyBooleanExprCheck>( "readability-simplify-boolean-expr"); CheckFactories.registerCheck<UniqueptrDeleteReleaseCheck>( Added: clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.cpp?rev=261939&view=auto ============================================================================== --- clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.cpp (added) +++ clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.cpp Thu Feb 25 17:57:23 2016 @@ -0,0 +1,62 @@ +//===- RedundantStringInitCheck.cpp - clang-tidy ----------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "RedundantStringInitCheck.h" +#include "clang/ASTMatchers/ASTMatchers.h" + +using namespace clang::ast_matchers; + +namespace clang { +namespace tidy { +namespace readability { + +namespace { + +AST_MATCHER(StringLiteral, lengthIsZero) { return Node.getLength() == 0; } + +} // namespace + +void RedundantStringInitCheck::registerMatchers(MatchFinder *Finder) { + if (!getLangOpts().CPlusPlus) + return; + + const auto StringCtorExpr = cxxConstructExpr( + hasDeclaration(cxxMethodDecl(hasName("basic_string"))), + argumentCountIs(2), + hasArgument(0, ignoringParenImpCasts(stringLiteral(lengthIsZero()))), + hasArgument(1, cxxDefaultArgExpr())); + + // string foo = ""; + // OR + // string bar(""); + Finder->addMatcher( + namedDecl(varDecl(hasType(cxxRecordDecl(hasName("basic_string"))), + hasInitializer( + expr(anyOf(StringCtorExpr, + exprWithCleanups(has(expr(anyOf( + StringCtorExpr, + cxxConstructExpr(hasArgument( + 0, cxxBindTemporaryExpr(has( + StringCtorExpr)))))))))) + .bind("expr")))) + .bind("decl"), + this); +} + +void RedundantStringInitCheck::check(const MatchFinder::MatchResult &Result) { + const auto *CtorExpr = Result.Nodes.getNodeAs<Expr>("expr"); + const auto *Decl = Result.Nodes.getNodeAs<NamedDecl>("decl"); + diag(CtorExpr->getExprLoc(), "redundant string initialization") + << FixItHint::CreateReplacement(CtorExpr->getSourceRange(), + Decl->getName()); +} + +} // namespace readability +} // namespace tidy +} // namespace clang Added: clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.h URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.h?rev=261939&view=auto ============================================================================== --- clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.h (added) +++ clang-tools-extra/trunk/clang-tidy/readability/RedundantStringInitCheck.h Thu Feb 25 17:57:23 2016 @@ -0,0 +1,32 @@ +//===- RedundantStringInitCheck.h - clang-tidy ------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_REDUNDANT_STRING_INIT_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_REDUNDANT_STRING_INIT_H + +#include "../ClangTidy.h" + +namespace clang { +namespace tidy { +namespace readability { + +/// Finds unnecessary string initializations. +class RedundantStringInitCheck : public ClangTidyCheck { +public: + RedundantStringInitCheck(StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context) {} + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; + +} // namespace readability +} // namespace tidy +} // namespace clang + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_REDUNDANT_STRING_INIT_H Modified: clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst?rev=261939&r1=261938&r2=261939&view=diff ============================================================================== --- clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst (original) +++ clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Thu Feb 25 17:57:23 2016 @@ -99,5 +99,6 @@ Clang-Tidy Checks readability-redundant-control-flow readability-redundant-smartptr-get readability-redundant-string-cstr + readability-redundant-string-init readability-simplify-boolean-expr readability-uniqueptr-delete-release Added: clang-tools-extra/trunk/docs/clang-tidy/checks/readability-redundant-string-init.rst URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/readability-redundant-string-init.rst?rev=261939&view=auto ============================================================================== --- clang-tools-extra/trunk/docs/clang-tidy/checks/readability-redundant-string-init.rst (added) +++ clang-tools-extra/trunk/docs/clang-tidy/checks/readability-redundant-string-init.rst Thu Feb 25 17:57:23 2016 @@ -0,0 +1,16 @@ +.. title:: clang-tidy - readability-redundant-string-init + +readability-redundant-string-init +================================= + + +Finds unnecessary string initializations. + +Examples: + +.. code:: c++ + + // Initializing string with empty string literal is unnecessary. + std::string a = ""; + std::string b(""); + Added: clang-tools-extra/trunk/test/clang-tidy/readability-redundant-string-init.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/readability-redundant-string-init.cpp?rev=261939&view=auto ============================================================================== --- clang-tools-extra/trunk/test/clang-tidy/readability-redundant-string-init.cpp (added) +++ clang-tools-extra/trunk/test/clang-tidy/readability-redundant-string-init.cpp Thu Feb 25 17:57:23 2016 @@ -0,0 +1,86 @@ +// RUN: %check_clang_tidy %s readability-redundant-string-init %t + +namespace std { +template <typename T> +class allocator {}; +template <typename T> +class char_traits {}; +template <typename C, typename T = std::char_traits<C>, typename A = std::allocator<C>> +struct basic_string { + basic_string(); + basic_string(const basic_string&); + basic_string(const C *, const A &a = A()); + ~basic_string(); +}; +typedef basic_string<char> string; +typedef basic_string<wchar_t> wstring; +} + +void f() { + std::string a = ""; + // CHECK-MESSAGES: [[@LINE-1]]:15: warning: redundant string initialization [readability-redundant-string-init] + // CHECK-FIXES: std::string a; + std::string b(""); + // CHECK-MESSAGES: [[@LINE-1]]:15: warning: redundant string initialization + // CHECK-FIXES: std::string b; + std::string c = R"()"; + // CHECK-MESSAGES: [[@LINE-1]]:15: warning: redundant string initialization + // CHECK-FIXES: std::string c; + std::string d(R"()"); + // CHECK-MESSAGES: [[@LINE-1]]:15: warning: redundant string initialization + // CHECK-FIXES: std::string d; + + std::string u = "u"; + std::string w("w"); + std::string x = R"(x)"; + std::string y(R"(y)"); + std::string z; +} + +void g() { + std::wstring a = L""; + // CHECK-MESSAGES: [[@LINE-1]]:16: warning: redundant string initialization + // CHECK-FIXES: std::wstring a; + std::wstring b(L""); + // CHECK-MESSAGES: [[@LINE-1]]:16: warning: redundant string initialization + // CHECK-FIXES: std::wstring b; + std::wstring c = LR"()"; + // CHECK-MESSAGES: [[@LINE-1]]:16: warning: redundant string initialization + // CHECK-FIXES: std::wstring c; + std::wstring d(LR"()"); + // CHECK-MESSAGES: [[@LINE-1]]:16: warning: redundant string initialization + // CHECK-FIXES: std::wstring d; + + std::wstring u = L"u"; + std::wstring w(L"w"); + std::wstring x = LR"(x)"; + std::wstring y(LR"(y)"); + std::wstring z; +} + +template <typename T> +void templ() { + std::string s = ""; + // CHECK-MESSAGES: [[@LINE-1]]:15: warning: redundant string initialization + // CHECK-FIXES: std::string s; +} + +#define M(x) x +#define N { std::string s = ""; } +// CHECK-FIXES: #define N { std::string s = ""; } + +void h() { + templ<int>(); + templ<double>(); + + M({ std::string s = ""; }) + // CHECK-MESSAGES: [[@LINE-1]]:19: warning: redundant string initialization + // CHECK-FIXES: M({ std::string s; }) + + N + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: redundant string initialization + // CHECK-FIXES: N + N + // CHECK-MESSAGES: [[@LINE-1]]:3: warning: redundant string initialization + // CHECK-FIXES: N +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
