--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/clang-tools-extra/clang-apply-replacements/tool/ClangApplyReplacementsMain.cpp	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,164 @@
+//===-- ClangApplyReplacementsMain.cpp - Main file for the tool -----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file provides the main function for the
+/// clang-apply-replacements tool.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang-apply-replacements/Tooling/ApplyReplacements.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Basic/Version.h"
+#include "clang/Format/Format.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/Support/CommandLine.h"
+
+using namespace llvm;
+using namespace clang;
+using namespace clang::replace;
+
+static cl::opt<std::string> Directory(cl::Positional, cl::Required,
+                                      cl::desc("<Search Root Directory>"));
+
+static cl::OptionCategory ReplacementCategory("Replacement Options");
+static cl::OptionCategory FormattingCategory("Formatting Options");
+
+const cl::OptionCategory *VisibleCategories[] = {&ReplacementCategory,
+                                                 &FormattingCategory};
+
+static cl::opt<bool> RemoveTUReplacementFiles(
+    "remove-change-desc-files",
+    cl::desc("Remove the change description files regardless of successful\n"
+             "merging/replacing."),
+    cl::init(false), cl::cat(ReplacementCategory));
+
+static cl::opt<bool> DoFormat(
+    "format",
+    cl::desc("Enable formatting of code changed by applying replacements.\n"
+             "Use -style to choose formatting style.\n"),
+    cl::cat(FormattingCategory));
+
+// FIXME: Consider making the default behaviour for finding a style
+// configuration file to start the search anew for every file being changed to
+// handle situations where the style is different for different parts of a
+// project.
+
+static cl::opt<std::string> FormatStyleConfig(
+    "style-config",
+    cl::desc("Path to a directory containing a .clang-format file\n"
+             "describing a formatting style to use for formatting\n"
+             "code when -style=file.\n"),
+    cl::init(""), cl::cat(FormattingCategory));
+
+static cl::opt<std::string>
+    FormatStyleOpt("style", cl::desc(format::StyleOptionHelpDescription),
+                   cl::init("LLVM"), cl::cat(FormattingCategory));
+
+namespace {
+// Helper object to remove the TUReplacement and TUDiagnostic (triggered by
+// "remove-change-desc-files" command line option) when exiting current scope.
+class ScopedFileRemover {
+public:
+  ScopedFileRemover(const TUReplacementFiles &Files,
+                    clang::DiagnosticsEngine &Diagnostics)
+      : TURFiles(Files), Diag(Diagnostics) {}
+
+  ~ScopedFileRemover() { deleteReplacementFiles(TURFiles, Diag); }
+
+private:
+  const TUReplacementFiles &TURFiles;
+  clang::DiagnosticsEngine &Diag;
+};
+} // namespace
+
+static void printVersion(raw_ostream &OS) {
+  OS << "clang-apply-replacements version " CLANG_VERSION_STRING << "\n";
+}
+
+int main(int argc, char **argv) {
+  cl::HideUnrelatedOptions(makeArrayRef(VisibleCategories));
+
+  cl::SetVersionPrinter(printVersion);
+  cl::ParseCommandLineOptions(argc, argv);
+
+  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts(new DiagnosticOptions());
+  DiagnosticsEngine Diagnostics(
+      IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()), DiagOpts.get());
+
+  // Determine a formatting style from options.
+  auto FormatStyleOrError = format::getStyle(FormatStyleOpt, FormatStyleConfig,
+                                             format::DefaultFallbackStyle);
+  if (!FormatStyleOrError) {
+    llvm::errs() << llvm::toString(FormatStyleOrError.takeError()) << "\n";
+    return 1;
+  }
+  format::FormatStyle FormatStyle = std::move(*FormatStyleOrError);
+
+  TUReplacements TURs;
+  TUReplacementFiles TUFiles;
+
+  std::error_code ErrorCode =
+      collectReplacementsFromDirectory(Directory, TURs, TUFiles, Diagnostics);
+
+  TUDiagnostics TUDs;
+  TUFiles.clear();
+  ErrorCode =
+      collectReplacementsFromDirectory(Directory, TUDs, TUFiles, Diagnostics);
+
+  if (ErrorCode) {
+    errs() << "Trouble iterating over directory '" << Directory
+           << "': " << ErrorCode.message() << "\n";
+    return 1;
+  }
+
+  // Remove the TUReplacementFiles (triggered by "remove-change-desc-files"
+  // command line option) when exiting main().
+  std::unique_ptr<ScopedFileRemover> Remover;
+  if (RemoveTUReplacementFiles)
+    Remover.reset(new ScopedFileRemover(TUFiles, Diagnostics));
+
+  FileManager Files((FileSystemOptions()));
+  SourceManager SM(Diagnostics, Files);
+
+  FileToChangesMap Changes;
+  if (!mergeAndDeduplicate(TURs, TUDs, Changes, SM))
+    return 1;
+
+  tooling::ApplyChangesSpec Spec;
+  Spec.Cleanup = true;
+  Spec.Style = FormatStyle;
+  Spec.Format = DoFormat ? tooling::ApplyChangesSpec::kAll
+                         : tooling::ApplyChangesSpec::kNone;
+
+  for (const auto &FileChange : Changes) {
+    const FileEntry *Entry = FileChange.first;
+    StringRef FileName = Entry->getName();
+    llvm::Expected<std::string> NewFileData =
+        applyChanges(FileName, FileChange.second, Spec, Diagnostics);
+    if (!NewFileData) {
+      errs() << llvm::toString(NewFileData.takeError()) << "\n";
+      continue;
+    }
+
+    // Write new file to disk
+    std::error_code EC;
+    llvm::raw_fd_ostream FileStream(FileName, EC, llvm::sys::fs::OF_None);
+    if (EC) {
+      llvm::errs() << "Could not open " << FileName << " for writing\n";
+      continue;
+    }
+    FileStream << *NewFileData;
+  }
+
+  return 0;
+}