From: Benjamin Kramer Date: Wed, 16 Jul 2014 10:00:14 +0000 (+0000) Subject: [clang-tidy] Add a checker that warns on const string & members. X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b1039759fb2d513f843030a16458d8420566abb6;p=platform%2Fupstream%2Fllvm.git [clang-tidy] Add a checker that warns on const string & members. Summary: Those are considered unsafe and should be replaced with simple pointers or full copies. It recognizes both std::string and ::string. Reviewers: alexfh, djasper Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D4522 llvm-svn: 213133 --- diff --git a/clang-tools-extra/clang-tidy/google/CMakeLists.txt b/clang-tools-extra/clang-tidy/google/CMakeLists.txt index 333ffff..0f62db9 100644 --- a/clang-tools-extra/clang-tidy/google/CMakeLists.txt +++ b/clang-tools-extra/clang-tidy/google/CMakeLists.txt @@ -7,6 +7,7 @@ add_clang_library(clangTidyGoogleModule GoogleTidyModule.cpp NamedParameterCheck.cpp OverloadedUnaryAndCheck.cpp + StringReferenceMemberCheck.cpp LINK_LIBS clangAST diff --git a/clang-tools-extra/clang-tidy/google/GoogleTidyModule.cpp b/clang-tools-extra/clang-tidy/google/GoogleTidyModule.cpp index 36e11d4..43eacfc3 100644 --- a/clang-tools-extra/clang-tidy/google/GoogleTidyModule.cpp +++ b/clang-tools-extra/clang-tidy/google/GoogleTidyModule.cpp @@ -15,6 +15,7 @@ #include "ExplicitMakePairCheck.h" #include "NamedParameterCheck.h" #include "OverloadedUnaryAndCheck.h" +#include "StringReferenceMemberCheck.h" using namespace clang::ast_matchers; @@ -34,6 +35,9 @@ public: "google-runtime-operator", new ClangTidyCheckFactory()); CheckFactories.addCheckFactory( + "google-runtime-member-string-references", + new ClangTidyCheckFactory()); + CheckFactories.addCheckFactory( "google-readability-casting", new ClangTidyCheckFactory()); CheckFactories.addCheckFactory( diff --git a/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.cpp b/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.cpp new file mode 100644 index 0000000..f7b5559 --- /dev/null +++ b/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.cpp @@ -0,0 +1,48 @@ +//===--- StringReferenceMemberCheck.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 "StringReferenceMemberCheck.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" +#include "clang/ASTMatchers/ASTMatchers.h" +#include "clang/AST/ASTContext.h" + +using namespace clang::ast_matchers; + +namespace clang { +namespace tidy { +namespace runtime { + +void StringReferenceMemberCheck::registerMatchers( + ast_matchers::MatchFinder *Finder) { + // Look for const references to std::string or ::string. + auto String = anyOf(recordDecl(hasName("::std::basic_string")), + recordDecl(hasName("::string"))); + auto ConstString = qualType(isConstQualified(), hasDeclaration(String)); + + // Ignore members in template instantiations. + auto InTemplateInstantiation = hasAncestor( + decl(anyOf(recordDecl(ast_matchers::isTemplateInstantiation()), + functionDecl(ast_matchers::isTemplateInstantiation())))); + + Finder->addMatcher(fieldDecl(hasType(references(ConstString)), + unless(InTemplateInstantiation)).bind("member"), + this); +} + +void +StringReferenceMemberCheck::check(const MatchFinder::MatchResult &Result) { + const auto *Member = Result.Nodes.getNodeAs("member"); + diag(Member->getLocStart(), "const string& members are dangerous. It is much " + "better to use alternatives, such as pointers or " + "simple constants."); +} + +} // namespace runtime +} // namespace tidy +} // namespace clang diff --git a/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.h b/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.h new file mode 100644 index 0000000..4b4bff6 --- /dev/null +++ b/clang-tools-extra/clang-tidy/google/StringReferenceMemberCheck.h @@ -0,0 +1,50 @@ +//===--- StringReferenceMemberCheck.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_GOOGLE_STRING_REF_MEMBER_CHECK_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_STRING_REF_MEMBER_CHECK_H + +#include "../ClangTidy.h" + +namespace clang { +namespace tidy { +namespace runtime { + +/// \brief Finds members of type 'const string&'. +/// +/// const string reference members are generally considered unsafe as they can +/// be created from a temporary quite easily. +/// +/// \code +/// struct S { +/// S(const string &Str) : Str(Str) {} +/// const string &Str; +/// }; +/// S instance("string"); +/// \endcode +/// +/// In the constructor call a string temporary is created from const char * and +/// destroyed immediately after the call. This leaves around a dangling +/// reference. +/// +/// This check emit warnings for both std::string and ::string const reference +/// members. +/// +/// Corresponding cpplint.py check name: 'runtime/member_string_reference'. +class StringReferenceMemberCheck : public ClangTidyCheck { +public: + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; + +} // namespace runtime +} // namespace tidy +} // namespace clang + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_STRING_REF_MEMBER_CHECK_H diff --git a/clang-tools-extra/test/clang-tidy/google-member-string-references.cpp b/clang-tools-extra/test/clang-tidy/google-member-string-references.cpp new file mode 100644 index 0000000..1536bad --- /dev/null +++ b/clang-tools-extra/test/clang-tidy/google-member-string-references.cpp @@ -0,0 +1,49 @@ +// RUN: clang-tidy %s -checks='-*,google-runtime-member-string-references' -- | FileCheck %s -implicit-check-not="{{warning|error}}:" + +namespace std { +template + class basic_string {}; + +typedef basic_string string; +} + +class string {}; + + +struct A { + const std::string &s; +// CHECK: :[[@LINE-1]]:3: warning: const string& members are dangerous. It is much better to use alternatives, such as pointers or simple constants. +}; + +struct B { + std::string &s; +}; + +struct C { + const std::string s; +}; + +template +struct D { + D(); + const T &s; + const std::string &s2; +// CHECK: :[[@LINE-1]]:3: warning: const string& members are dangerous. It is much better to use alternatives, such as pointers or simple constants. +}; + +D d; + +struct AA { + const string &s; +// CHECK: :[[@LINE-1]]:3: warning: const string& members are dangerous. It is much better to use alternatives, such as pointers or simple constants. +}; + +struct BB { + string &s; +}; + +struct CC { + const string s; +}; + +D dd;