Make tooling::applyAllReplacements return llvm::Expected<string> instead of empty string to indicate potential error.

Summary:
return llvm::Expected<> to carry error status and error information.
This is the first step towards introducing "Error" into tooling::Replacements.

Reviewers: djasper, klimek

Subscribers: ioeric, klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D21601

llvm-svn: 275062

1 files changed, 6 insertions, 2 deletions

diff --git a/clang/lib/Tooling/Refactoring.cpp b/clang/lib/Tooling/Refactoring.cpp
index 51f0635c..28d535a 100644
--- a/clang/lib/Tooling/Refactoring.cpp
+++ b/clang/lib/Tooling/Refactoring.cpp
@@ -79,9 +79,13 @@ bool formatAndApplyAllReplacements(const Replacements &Replaces,
     StringRef Code = SM.getBufferData(ID);
 
     format::FormatStyle CurStyle = format::getStyle(Style, FilePath, "LLVM");
-    Replacements NewReplacements =
+    auto NewReplacements =
         format::formatReplacements(Code, CurReplaces, CurStyle);
-    Result = applyAllReplacements(NewReplacements, Rewrite) && Result;
+    if (!NewReplacements) {
+      llvm::errs() << llvm::toString(NewReplacements.takeError()) << "\n";
+      return false;
+    }
+    Result = applyAllReplacements(*NewReplacements, Rewrite) && Result;
   }
   return Result;
 }