gistfile1.txt

class ReplacementsTest : public MatchFinder::MatchCallback {
    using reps_t = std::map<std::string, Replacements>;
public:
    ReplacementsTest(reps_t *reps) : Replace(reps)  {}
    virtual void run(const MatchFinder::MatchResult &Result) {
        clang::ASTContext *Context = Result.Context;
        const clang::FunctionDecl *FS = Result.Nodes.getNodeAs<clang::FunctionDecl>("funcdecl");
        if (!FS || !Context->getSourceManager().isWrittenInMainFile(FS->getLocStart()))
            return;
        else{
            clang::SourceRange sr = FS->getSourceRange();
            std::string s = std::string("//test123\n");
            auto *sm = &Context->getSourceManager();
            auto fpath =  sm->getFilename(FS->getLocation()).str();
            Replacement Rep(*(Result.SourceManager), sr.getBegin(), 0, s);
            auto res = Replace->insert(std::pair<std::string, Replacements>(fpath, Replacements(Rep)));
            if (res.second == false) {
              llvm::errs() << "map error\n";
            }
        }
    }
private:
    reps_t *Replace;
};

int main(int argc, const char **argv) {
    CommonOptionsParser OptionsParser(argc, argv, MyToolCategory);
    ClangTool Tool(OptionsParser.getCompilations(),
                   OptionsParser.getSourcePathList());
    // how the following line should look like?
    // as RefactoringTool was in place, i was doing:               
    ReplacementsTest rtest(&Tool.getReplacements());
    MatchFinder Finder;

    StatementMatcher LoopMatcher = forStmt().bind("forLoop");
    DeclarationMatcher FuncMatcher = functionDecl(isDefinition()).bind("funcdecl");
    Finder.addMatcher(FuncMatcher, &rtest);
    if(int result =  Tool.run(newFrontendActionFactory(&Finder).get())){
      return result;
    }
}