Remove code duplication and cut dependency from clangRewrite on clangAst.

[klimek]

Seems reasonable, but I'd like somebody who is more knowledgable about ARCMT to sign off on this.

Just to make sure: you did test this with CLANG_ENABLE_ARCMT enabled?

[djasper]

Yes, tested with CLANG_ENABLE_ARCMT.

[akyrtzi]

LGTM.

include/clang/Rewrite/Core/Rewriter.h

bool ReplaceText(SourceRange range, StringRef NewStr) {
     return ReplaceText(range.getBegin(), getRangeSize(range), NewStr);
   }
 
   /// ReplaceText - This method replaces a range of characters in the input
   /// buffer with a new string.  This is effectively a combined "remove/insert"
   /// operation.
   bool ReplaceText(SourceRange range, SourceRange replacementRange);
 
-  /// ReplaceStmt - This replaces a Stmt/Expr with another, using the pretty
-  /// printer to generate the replacement code.  This returns true if the input
-  /// could not be rewritten, or false if successful.
-  bool ReplaceStmt(Stmt *From, Stmt *To);
-
   /// \brief Increase indentation for the lines between the given source range.
   /// To determine what the indentation should be, 'parentIndent' is used
   /// that should be at a source location with an indentation one degree
   /// lower than the given range.
   bool IncreaseIndentation(CharSourceRange range, SourceLocation parentIndent);
   bool IncreaseIndentation(SourceRange range, SourceLocation parentIndent) {
     return IncreaseIndentation(CharSourceRange::getTokenRange(range),
                                parentIndent);

lib/Frontend/Rewrite/RewriteModernObjC.cpp

RewriteModernObjC(std::string inFile, raw_ostream *OS,
                 DiagnosticsEngine &D, const LangOptions &LOpts,
                 bool silenceMacroWarn, bool LineInfo);
     
     ~RewriteModernObjC() {}
 
     void HandleTranslationUnit(ASTContext &C) override;
 
     void ReplaceStmt(Stmt *Old, Stmt *New) {
-      Stmt *ReplacingStmt = ReplacedNodes[Old];
-
-      if (ReplacingStmt)
-        return; // We can't rewrite the same node twice.
-
-      if (DisableReplaceStmt)
-        return;
-
-      // If replacement succeeded or warning disabled return with no warning.
-      if (!Rewrite.ReplaceStmt(Old, New)) {
-        ReplacedNodes[Old] = New;
-        return;
-      }
-      if (SilenceRewriteMacroWarning)
-        return;
-      Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
-                   << Old->getSourceRange();
+      ReplaceStmtWithRange(Old, New, Old->getSourceRange());
     }
 
     void ReplaceStmtWithRange(Stmt *Old, Stmt *New, SourceRange SrcRange) {
       assert(Old != nullptr && New != nullptr && "Expected non-null Stmt's");
+
+      Stmt *ReplacingStmt = ReplacedNodes[Old];
+      if (ReplacingStmt)
+        return; // We can't rewrite the same node twice.
+
       if (DisableReplaceStmt)
         return;
 
       // Measure the old text.
       int Size = Rewrite.getRangeSize(SrcRange);
       if (Size == -1) {
         Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
                      << Old->getSourceRange();

lib/Frontend/Rewrite/RewriteObjC.cpp

RewriteObjC(std::string inFile, raw_ostream *OS,
                 DiagnosticsEngine &D, const LangOptions &LOpts,
                 bool silenceMacroWarn);
 
     ~RewriteObjC() {}
 
     void HandleTranslationUnit(ASTContext &C) override;
 
     void ReplaceStmt(Stmt *Old, Stmt *New) {
-      Stmt *ReplacingStmt = ReplacedNodes[Old];
-
-      if (ReplacingStmt)
-        return; // We can't rewrite the same node twice.
-
-      if (DisableReplaceStmt)
-        return;
-
-      // If replacement succeeded or warning disabled return with no warning.
-      if (!Rewrite.ReplaceStmt(Old, New)) {
-        ReplacedNodes[Old] = New;
-        return;
-      }
-      if (SilenceRewriteMacroWarning)
-        return;
-      Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
-                   << Old->getSourceRange();
+      ReplaceStmtWithRange(Old, New, Old->getSourceRange());
     }
 
     void ReplaceStmtWithRange(Stmt *Old, Stmt *New, SourceRange SrcRange) {
       assert(Old != nullptr && New != nullptr && "Expected non-null Stmt's");
+
+      Stmt *ReplacingStmt = ReplacedNodes[Old];
+      if (ReplacingStmt)
+        return; // We can't rewrite the same node twice.
+
       if (DisableReplaceStmt)
         return;
 
       // Measure the old text.
       int Size = Rewrite.getRangeSize(SrcRange);
       if (Size == -1) {
         Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
                      << Old->getSourceRange();

lib/Rewrite/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   Support
   )
 
 add_clang_library(clangRewrite
   DeltaTree.cpp
   HTMLRewrite.cpp
   RewriteRope.cpp
   Rewriter.cpp
   TokenRewriter.cpp
 
   LINK_LIBS
-  clangAST
   clangBasic
   clangLex
   )

lib/Rewrite/Rewriter.cpp

bool Rewriter::ReplaceText(SourceRange range, SourceRange replacementRange) {
   unsigned newLength = getRangeSize(replacementRange);
   FileID FID;
   unsigned newOffs = getLocationOffsetAndFileID(replacementRange.getBegin(),
                                                 FID);
   StringRef MB = SourceMgr->getBufferData(FID);
   return ReplaceText(start, origLength, MB.substr(newOffs, newLength));
 }
 
-/// ReplaceStmt - This replaces a Stmt/Expr with another, using the pretty
-/// printer to generate the replacement code.  This returns true if the input
-/// could not be rewritten, or false if successful.
-bool Rewriter::ReplaceStmt(Stmt *From, Stmt *To) {
-  assert(From != nullptr && To != nullptr && "Expected non-null Stmt's");
-
-  // Measaure the old text.
-  int Size = getRangeSize(From->getSourceRange());
-  if (Size == -1)
-    return true;
-
-  // Get the new text.
-  std::string SStr;
-  llvm::raw_string_ostream S(SStr);
-  To->printPretty(S, nullptr, PrintingPolicy(*LangOpts));
-  const std::string &Str = S.str();
-
-  ReplaceText(From->getLocStart(), Size, Str);
-  return false;
-}
-
 std::string Rewriter::ConvertToString(Stmt *From) {
   assert(From != nullptr && "Expected non-null Stmt");
   std::string SStr;
   llvm::raw_string_ostream S(SStr);
   From->printPretty(S, nullptr, PrintingPolicy(*LangOpts));
   return S.str();
 }