clang-tools-extra/clang-change-namespace/tool/ClangChangeNamespace.cpp

   1 //===-- ClangChangeNamespace.cpp - Standalone change namespace ------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 // This tool can be used to change the surrounding namespaces of class/function
   9 // definitions.
  10 //
  11 // Example: test.cc
  12 //    namespace na {
  13 //    class X {};
  14 //    namespace nb {
  15 //    class Y { X x; };
  16 //    } // namespace nb
  17 //    } // namespace na
  18 // To move the definition of class Y from namespace "na::nb" to "x::y", run:
  19 //    clang-change-namespace --old_namespace "na::nb" \
  20 //      --new_namespace "x::y" --file_pattern "test.cc" test.cc --
  21 // Output:
  22 //    namespace na {
  23 //    class X {};
  24 //    } // namespace na
  25 //    namespace x {
  26 //    namespace y {
  27 //    class Y { na::X x; };
  28 //    } // namespace y
  29 //    } // namespace x
  30
  31 #include "ChangeNamespace.h"
  32 #include "clang/ASTMatchers/ASTMatchFinder.h"
  33 #include "clang/Frontend/FrontendActions.h"
  34 #include "clang/Frontend/TextDiagnosticPrinter.h"
  35 #include "clang/Rewrite/Core/Rewriter.h"
  36 #include "clang/Tooling/CommonOptionsParser.h"
  37 #include "clang/Tooling/Refactoring.h"
  38 #include "clang/Tooling/Tooling.h"
  39 #include "llvm/Support/CommandLine.h"
  40 #include "llvm/Support/Signals.h"
  41 #include "llvm/Support/YAMLTraits.h"
  42
  43 using namespace clang;
  44 using namespace llvm;
  45
  46 namespace {
  47
  48 cl::OptionCategory ChangeNamespaceCategory("Change namespace.");
  49
  50 cl::opt<std::string> OldNamespace("old_namespace", cl::Required,
  51                                   cl::desc("Old namespace."),
  52                                   cl::cat(ChangeNamespaceCategory));
  53
  54 cl::opt<std::string> NewNamespace("new_namespace", cl::Required,
  55                                   cl::desc("New namespace."),
  56                                   cl::cat(ChangeNamespaceCategory));
  57
  58 cl::opt<std::string> FilePattern(
  59     "file_pattern", cl::Required,
  60     cl::desc("Only rename namespaces in files that match the given pattern."),
  61     cl::cat(ChangeNamespaceCategory));
  62
  63 cl::opt<bool> Inplace("i", cl::desc("Inplace edit <file>s, if specified."),
  64                       cl::cat(ChangeNamespaceCategory));
  65
  66 cl::opt<bool>
  67     DumpYAML("dump_result",
  68          cl::desc("Dump new file contents in YAML, if specified."),
  69          cl::cat(ChangeNamespaceCategory));
  70
  71 cl::opt<std::string> Style("style",
  72                            cl::desc("The style name used for reformatting."),
  73                            cl::init("LLVM"), cl::cat(ChangeNamespaceCategory));
  74
  75 cl::opt<std::string> AllowedFile(
  76     "allowed_file",
  77     cl::desc("A file containing regexes of symbol names that are not expected "
  78              "to be updated when changing namespaces around them."),
  79     cl::init(""), cl::cat(ChangeNamespaceCategory));
  80
  81 llvm::ErrorOr<std::vector<std::string>> GetAllowedSymbolPatterns() {
  82   std::vector<std::string> Patterns;
  83   if (AllowedFile.empty())
  84     return Patterns;
  85
  86   llvm::SmallVector<StringRef, 8> Lines;
  87   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
  88       llvm::MemoryBuffer::getFile(AllowedFile);
  89   if (!File)
  90     return File.getError();
  91   llvm::StringRef Content = File.get()->getBuffer();
  92   Content.split(Lines, '\n', /*MaxSplit=*/-1, /*KeepEmpty=*/false);
  93   for (auto Line : Lines)
  94     Patterns.push_back(std::string(Line.trim()));
  95   return Patterns;
  96 }
  97
  98 } // anonymous namespace
  99
 100 int main(int argc, const char **argv) {
 101   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
 102   auto ExpectedParser =
 103       tooling::CommonOptionsParser::create(argc, argv, ChangeNamespaceCategory);
 104   if (!ExpectedParser) {
 105     llvm::errs() << ExpectedParser.takeError();
 106     return 1;
 107   }
 108   tooling::CommonOptionsParser &OptionsParser = ExpectedParser.get();
 109   const auto &Files = OptionsParser.getSourcePathList();
 110   tooling::RefactoringTool Tool(OptionsParser.getCompilations(), Files);
 111   llvm::ErrorOr<std::vector<std::string>> AllowedPatterns =
 112       GetAllowedSymbolPatterns();
 113   if (!AllowedPatterns) {
 114     llvm::errs() << "Failed to open allow file " << AllowedFile << ". "
 115                  << AllowedPatterns.getError().message() << "\n";
 116     return 1;
 117   }
 118   change_namespace::ChangeNamespaceTool NamespaceTool(
 119       OldNamespace, NewNamespace, FilePattern, *AllowedPatterns,
 120       &Tool.getReplacements(), Style);
 121   ast_matchers::MatchFinder Finder;
 122   NamespaceTool.registerMatchers(&Finder);
 123   std::unique_ptr<tooling::FrontendActionFactory> Factory =
 124       tooling::newFrontendActionFactory(&Finder);
 125
 126   if (int Result = Tool.run(Factory.get()))
 127     return Result;
 128   LangOptions DefaultLangOptions;
 129   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
 130   clang::TextDiagnosticPrinter DiagnosticPrinter(errs(), &*DiagOpts);
 131   DiagnosticsEngine Diagnostics(
 132       IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()), &*DiagOpts,
 133       &DiagnosticPrinter, false);
 134   auto &FileMgr = Tool.getFiles();
 135   SourceManager Sources(Diagnostics, FileMgr);
 136   Rewriter Rewrite(Sources, DefaultLangOptions);
 137
 138   if (!formatAndApplyAllReplacements(Tool.getReplacements(), Rewrite, Style)) {
 139     llvm::errs() << "Failed applying all replacements.\n";
 140     return 1;
 141   }
 142   if (Inplace)
 143     return Rewrite.overwriteChangedFiles();
 144
 145   std::set<llvm::StringRef> ChangedFiles;
 146   for (const auto &it : Tool.getReplacements())
 147     ChangedFiles.insert(it.first);
 148
 149   if (DumpYAML) {
 150     auto WriteToYAML = [&](llvm::raw_ostream &OS) {
 151       OS << "[\n";
 152       for (auto I = ChangedFiles.begin(), E = ChangedFiles.end(); I != E; ++I) {
 153         OS << "  {\n";
 154         OS << "    \"FilePath\": \"" << *I << "\",\n";
 155         auto Entry = llvm::cantFail(FileMgr.getFileRef(*I));
 156         auto ID = Sources.getOrCreateFileID(Entry, SrcMgr::C_User);
 157         std::string Content;
 158         llvm::raw_string_ostream ContentStream(Content);
 159         Rewrite.getEditBuffer(ID).write(ContentStream);
 160         OS << "    \"SourceText\": \""
 161            << llvm::yaml::escape(ContentStream.str()) << "\"\n";
 162         OS << "  }";
 163         if (I != std::prev(E))
 164           OS << ",\n";
 165       }
 166       OS << "\n]\n";
 167     };
 168     WriteToYAML(llvm::outs());
 169     return 0;
 170   }
 171
 172   for (const auto &File : ChangedFiles) {
 173     auto Entry = llvm::cantFail(FileMgr.getFileRef(File));
 174
 175     auto ID = Sources.getOrCreateFileID(Entry, SrcMgr::C_User);
 176     outs() << "============== " << File << " ==============\n";
 177     Rewrite.getEditBuffer(ID).write(llvm::outs());
 178     outs() << "\n============================================\n";
 179   }
 180
 181   return 0;
 182 }