Add new code migrator support for migrating existing Objective-C code to use

the new Objective-C NSArray/NSDictionary/NSNumber literal syntax.

This introduces a new library, libEdit, which provides a new way to support
migration of code that improves on the original ARC migrator.  We now believe
that most of its functionality can be refactored into the existing libraries,
and thus this new library may shortly disappear.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152141 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 43 insertions, 26 deletions

diff --git a/lib/Rewrite/FixItRewriter.cpp b/lib/Rewrite/FixItRewriter.cpp
index caa7d06ac2..3863adb4f1 100644
--- a/lib/Rewrite/FixItRewriter.cpp
+++ b/lib/Rewrite/FixItRewriter.cpp
@@ -14,6 +14,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Rewrite/FixItRewriter.h"
+#include "clang/Edit/Commit.h"
+#include "clang/Edit/EditsReceiver.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/SourceLocation.h"
 #include "clang/Basic/SourceManager.h"
@@ -29,6 +31,7 @@ FixItRewriter::FixItRewriter(DiagnosticsEngine &Diags, SourceManager &SourceMgr,
                              const LangOptions &LangOpts,
                              FixItOptions *FixItOpts)
   : Diags(Diags),
+    Editor(SourceMgr, LangOpts),
     Rewrite(SourceMgr, LangOpts),
     FixItOpts(FixItOpts),
     NumFailures(0),
@@ -51,6 +54,24 @@ bool FixItRewriter::WriteFixedFile(FileID ID, raw_ostream &OS) {
   return false;
 }
 
+namespace {
+
+class RewritesReceiver : public edit::EditsReceiver {
+  Rewriter &Rewrite;
+
+public:
+  RewritesReceiver(Rewriter &Rewrite) : Rewrite(Rewrite) { }
+
+  virtual void insert(SourceLocation loc, StringRef text) {
+    Rewrite.InsertText(loc, text);
+  }
+  virtual void replace(CharSourceRange range, StringRef text) {
+    Rewrite.ReplaceText(range.getBegin(), Rewrite.getRangeSize(range), text);
+  }
+};
+
+}
+
 bool FixItRewriter::WriteFixedFiles(
             std::vector<std::pair<std::string, std::string> > *RewrittenFiles) {
   if (NumFailures > 0 && !FixItOpts->FixWhatYouCan) {
@@ -58,6 +79,9 @@ bool FixItRewriter::WriteFixedFiles(
     return true;
   }
 
+  RewritesReceiver Rec(Rewrite);
+  Editor.applyRewrites(Rec);
+
   for (iterator I = buffer_begin(), E = buffer_end(); I != E; ++I) {
     const FileEntry *Entry = Rewrite.getSourceMgr().getFileEntryForID(I->first);
     int fd;
@@ -116,16 +140,28 @@ void FixItRewriter::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
 
   // Make sure that we can perform all of the modifications we
   // in this diagnostic.
-  bool CanRewrite = Info.getNumFixItHints() > 0;
+  edit::Commit commit(Editor);
   for (unsigned Idx = 0, Last = Info.getNumFixItHints();
        Idx < Last; ++Idx) {
     const FixItHint &Hint = Info.getFixItHint(Idx);
-    if (Hint.RemoveRange.isValid() &&
-        Rewrite.getRangeSize(Hint.RemoveRange) == -1) {
-      CanRewrite = false;
-      break;
+
+    if (Hint.CodeToInsert.empty()) {
+      if (Hint.InsertFromRange.isValid())
+        commit.insertFromRange(Hint.RemoveRange.getBegin(),
+                           Hint.InsertFromRange, /*afterToken=*/false,
+                           Hint.BeforePreviousInsertions);
+      else
+        commit.remove(Hint.RemoveRange);
+    } else {
+      if (Hint.RemoveRange.isTokenRange() ||
+          Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
+        commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
+      else
+        commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
+                    /*afterToken=*/false, Hint.BeforePreviousInsertions);
     }
   }
+  bool CanRewrite = Info.getNumFixItHints() > 0 && commit.isCommitable();
 
   if (!CanRewrite) {
     if (Info.getNumFixItHints() > 0)
@@ -138,27 +174,8 @@ void FixItRewriter::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
     }
     return;
   }
-
-  bool Failed = false;
-  for (unsigned Idx = 0, Last = Info.getNumFixItHints();
-       Idx < Last; ++Idx) {
-    const FixItHint &Hint = Info.getFixItHint(Idx);
-
-    if (Hint.CodeToInsert.empty()) {
-      // We're removing code.
-      if (Rewrite.RemoveText(Hint.RemoveRange))
-        Failed = true;
-      continue;
-    }
-
-    // We're replacing code.
-    if (Rewrite.ReplaceText(Hint.RemoveRange.getBegin(),
-                            Rewrite.getRangeSize(Hint.RemoveRange),
-                            Hint.CodeToInsert))
-      Failed = true;
-  }
-
-  if (Failed) {
+  
+  if (!Editor.commit(commit)) {
     ++NumFailures;
     Diag(Info.getLocation(), diag::note_fixit_failed);
     return;