Introducing Use-Auto transform for cpp11-migrate

The new Use-Auto transform replaces the type specifier for variable
declarations with the special C++11 'auto' type specifier. For now, the
replacement is done only for variables that are iterators of any of the
std containers and only if the type used is one of those explicitly
allowed by the standard (i.e. not an implementation-specific type).

Reviewers: gribozavr, silvas, klimek
llvm-svn: 176266

1 files changed, 58 insertions, 0 deletions

diff --git a/clang-tools-extra/cpp11-migrate/UseAuto/UseAuto.cpp b/clang-tools-extra/cpp11-migrate/UseAuto/UseAuto.cpp
new file mode 100644
index 00000000000..00723cab218
--- /dev/null
+++ b/clang-tools-extra/cpp11-migrate/UseAuto/UseAuto.cpp
@@ -0,0 +1,58 @@
+//===-- UseAuto/UseAuto.cpp - Use auto type specifier ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file provides the implementation of the UseAutoTransform class.
+///
+//===----------------------------------------------------------------------===//
+
+#include "UseAuto.h"
+#include "UseAutoActions.h"
+#include "UseAutoMatchers.h"
+
+using clang::ast_matchers::MatchFinder;
+using namespace clang;
+using namespace clang::tooling;
+
+int UseAutoTransform::apply(const FileContentsByPath &InputStates,
+                            RiskLevel MaxRisk,
+                            const clang::tooling::CompilationDatabase &Database,
+                            const std::vector<std::string> &SourcePaths,
+                            FileContentsByPath &ResultStates) {
+  RefactoringTool UseAutoTool(Database, SourcePaths);
+
+  for (FileContentsByPath::const_iterator I = InputStates.begin(),
+                                          E = InputStates.end();
+       I != E; ++I)
+    UseAutoTool.mapVirtualFile(I->first, I->second);
+
+  unsigned AcceptedChanges = 0;
+
+  MatchFinder Finder;
+  UseAutoFixer Fixer(UseAutoTool.getReplacements(), AcceptedChanges, MaxRisk);
+
+  Finder.addMatcher(makeIteratorMatcher(), &Fixer);
+
+  if (int Result = UseAutoTool.run(newFrontendActionFactory(&Finder))) {
+    llvm::errs() << "Error encountered during translation.\n";
+    return Result;
+  }
+
+  RewriterContainer Rewrite(UseAutoTool.getFiles(), InputStates);
+
+  // FIXME: Do something if some replacements didn't get applied?
+  UseAutoTool.applyAllReplacements(Rewrite.getRewriter());
+
+  collectResults(Rewrite.getRewriter(), InputStates, ResultStates);
+
+  if (AcceptedChanges > 0)
+    setChangesMade();
+
+  return 0;
+}