1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 //
5 // This file containts a clang tool to update base::Bind() callers:
6 // * Remove unneeded scoped_refptr<>::get() on method binding.
7
8 #include <assert.h>
9 #include <algorithm>
10 #include <memory>
11 #include <string>
12
13 #include "clang/AST/ASTContext.h"
14 #include "clang/ASTMatchers/ASTMatchers.h"
15 #include "clang/ASTMatchers/ASTMatchersMacros.h"
16 #include "clang/ASTMatchers/ASTMatchFinder.h"
17 #include "clang/Basic/SourceManager.h"
18 #include "clang/Frontend/FrontendActions.h"
19 #include "clang/Lex/Lexer.h"
20 #include "clang/Tooling/CommonOptionsParser.h"
21 #include "clang/Tooling/Refactoring.h"
22 #include "clang/Tooling/Tooling.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/TargetSelect.h"
25
26 using namespace clang::ast_matchers;
27 using clang::tooling::CommonOptionsParser;
28 using Replacements = std::vector<clang::tooling::Replacement>;
29
30 namespace {
31
32 // Remove unneeded scoped_refptr<>::get on a receivers of method bind.
33 // Example:
34 // // Before
35 // scoped_refptr<Foo> foo;
36 // base::Bind(&Foo::Bar, foo.get());
37 //
38 // // After
39 // scoped_refptr<Foo> foo;
40 // base::Bind(&Foo::Bar, foo);
41 //
42 class ScopedRefptrGetRewriter : public MatchFinder::MatchCallback {
43 public:
ScopedRefptrGetRewriter(Replacements * replacements)44 explicit ScopedRefptrGetRewriter(Replacements* replacements)
45 : replacements_(replacements) {}
46
GetMatcher()47 StatementMatcher GetMatcher() {
48 auto is_bind_call = callee(namedDecl(hasName("::base::Bind")));
49 auto is_method_bind = hasArgument(0, hasType(memberPointerType()));
50 auto is_raw_pointer_receiver = hasArgument(1, hasType(pointerType()));
51 auto is_scoped_refptr_get_call =
52 cxxMemberCallExpr(thisPointerType(namedDecl(hasName("scoped_refptr"))),
53 callee(namedDecl(hasName("get"))));
54 return callExpr(is_bind_call, is_method_bind, is_raw_pointer_receiver,
55 hasArgument(1, is_scoped_refptr_get_call),
56 hasArgument(1, stmt().bind("target")));
57 }
58
run(const MatchFinder::MatchResult & result)59 void run(const MatchFinder::MatchResult& result) override {
60 auto* target = result.Nodes.getNodeAs<clang::CXXMemberCallExpr>("target");
61 auto* member = llvm::cast<clang::MemberExpr>(target->getCallee());
62 assert(target && member && "Unexpected match! No Expr captured!");
63 auto range = clang::CharSourceRange::getTokenRange(
64 result.SourceManager->getSpellingLoc(member->getOperatorLoc()),
65 result.SourceManager->getSpellingLoc(target->getLocEnd()));
66
67 replacements_->emplace_back(*result.SourceManager, range, "");
68 }
69
70 private:
71 Replacements* replacements_;
72 };
73
74 llvm::cl::extrahelp common_help(CommonOptionsParser::HelpMessage);
75
76 } // namespace.
77
main(int argc,const char * argv[])78 int main(int argc, const char* argv[]) {
79 llvm::InitializeNativeTarget();
80 llvm::InitializeNativeTargetAsmParser();
81 llvm::cl::OptionCategory category(
82 "Remove raw pointer on the receiver of Bind() target");
83 CommonOptionsParser options(argc, argv, category);
84 clang::tooling::ClangTool tool(options.getCompilations(),
85 options.getSourcePathList());
86
87 MatchFinder match_finder;
88 std::vector<clang::tooling::Replacement> replacements;
89
90
91 ScopedRefptrGetRewriter scoped_refptr_rewriter(&replacements);
92 match_finder.addMatcher(scoped_refptr_rewriter.GetMatcher(),
93 &scoped_refptr_rewriter);
94
95 std::unique_ptr<clang::tooling::FrontendActionFactory> factory =
96 clang::tooling::newFrontendActionFactory(&match_finder);
97 int result = tool.run(factory.get());
98 if (result != 0)
99 return result;
100
101 // Serialization format is documented in tools/clang/scripts/run_tool.py
102 llvm::outs() << "==== BEGIN EDITS ====\n";
103 for (const auto& r : replacements) {
104 std::string replacement_text = r.getReplacementText().str();
105 std::replace(replacement_text.begin(), replacement_text.end(), '\n', '\0');
106 llvm::outs() << "r:::" << r.getFilePath() << ":::" << r.getOffset()
107 << ":::" << r.getLength() << ":::" << replacement_text << "\n";
108 }
109 llvm::outs() << "==== END EDITS ====\n";
110
111 return 0;
112 }
113