tools/clang/rewrite_scoped_array/RewriteScopedArray.cpp

   1 // Copyright (c) 2013 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 implements a Clang tool to rewrite all instances of scoped_array<T> to
   6 // scoped_ptr<T[]>. The former is being deprecated in favor of the latter, to
   7 // allow for an eventual transition from scoped_ptr to unique_ptr.
   8
   9 #include "clang/AST/ASTContext.h"
  10 #include "clang/ASTMatchers/ASTMatchers.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12 #include "clang/Basic/SourceManager.h"
  13 #include "clang/Frontend/FrontendActions.h"
  14 #include "clang/Lex/Lexer.h"
  15 #include "clang/Tooling/CommonOptionsParser.h"
  16 #include "clang/Tooling/Refactoring.h"
  17 #include "clang/Tooling/Tooling.h"
  18 #include "llvm/Support/CommandLine.h"
  19
  20 using clang::ast_matchers::MatchFinder;
  21 using clang::ast_matchers::hasDeclaration;
  22 using clang::ast_matchers::hasName;
  23 using clang::ast_matchers::id;
  24 using clang::ast_matchers::loc;
  25 using clang::ast_matchers::qualType;
  26 using clang::ast_matchers::recordDecl;
  27 using clang::tooling::CommonOptionsParser;
  28 using clang::tooling::Replacement;
  29 using clang::tooling::Replacements;
  30 using llvm::StringRef;
  31
  32 namespace {
  33
  34 class RewriterCallback : public MatchFinder::MatchCallback {
  35  public:
  36   RewriterCallback(Replacements* replacements) : replacements_(replacements) {}
  37   virtual void run(const MatchFinder::MatchResult& result) LLVM_OVERRIDE;
  38
  39  private:
  40   Replacements* const replacements_;
  41 };
  42
  43 void RewriterCallback::run(const MatchFinder::MatchResult& result) {
  44   const clang::TypeLoc type_location =
  45       *result.Nodes.getNodeAs<clang::TypeLoc>("loc");
  46   clang::CharSourceRange range = clang::CharSourceRange::getTokenRange(
  47       result.SourceManager->getSpellingLoc(type_location.getLocStart()),
  48       result.SourceManager->getSpellingLoc(type_location.getLocEnd()));
  49   // TODO(dcheng): Log an error?
  50   if (!range.isValid())
  51     return;
  52   std::string replacement_text = clang::Lexer::getSourceText(
  53       range, *result.SourceManager, result.Context->getLangOpts());
  54   // TODO(dcheng): Log errors?
  55   if (!StringRef(replacement_text).startswith("scoped_array<") ||
  56       !StringRef(replacement_text).endswith(">"))
  57     return;
  58   replacement_text.replace(strlen("scoped_"), strlen("array"), "ptr");
  59   replacement_text.insert(replacement_text.size() - 1, "[]");
  60   replacements_->insert(
  61       Replacement(*result.SourceManager, range, replacement_text));
  62 }
  63
  64 }  // namespace
  65
  66 static llvm::cl::extrahelp common_help(CommonOptionsParser::HelpMessage);
  67
  68 int main(int argc, const char* argv[]) {
  69   CommonOptionsParser options(argc, argv);
  70   clang::tooling::ClangTool tool(options.getCompilations(),
  71                                  options.getSourcePathList());
  72
  73   Replacements replacements;
  74   RewriterCallback callback(&replacements);
  75   MatchFinder match_finder;
  76   match_finder.addMatcher(
  77       id("loc",
  78          loc(qualType(hasDeclaration(recordDecl(hasName("::scoped_array")))))),
  79       &callback);
  80
  81   int result =
  82       tool.run(clang::tooling::newFrontendActionFactory(&match_finder));
  83   if (result != 0)
  84     return result;
  85
  86   // Serialization format is documented in tools/clang/scripts/run_tool.py
  87   llvm::outs() << "==== BEGIN EDITS ====\n";
  88   for (Replacements::const_iterator it = replacements.begin();
  89        it != replacements.end(); ++it) {
  90     llvm::outs() << "r:" << it->getFilePath() << ":" << it->getOffset() << ":"
  91                  << it->getLength() << ":" << it->getReplacementText() << "\n";
  92   }
  93   llvm::outs() << "==== END EDITS ====\n";
  94
  95   return 0;
  96 }