[clang-tidy] Add an option to export suggested fixes into a file.

Allows gathering fixes and applying them with clang-apply-fixes.

Differential Revision: http://reviews.llvm.org/D5176

llvm-svn: 217139
diff --git a/clang-tools-extra/test/clang-tidy/fix.cpp b/clang-tools-extra/test/clang-tidy/fix.cpp
index f82ed0b..80b215d 100644
--- a/clang-tools-extra/test/clang-tidy/fix.cpp
+++ b/clang-tools-extra/test/clang-tidy/fix.cpp
@@ -1,14 +1,17 @@
 // RUN: grep -Ev "// *[A-Z-]+:" %s > %t.cpp
-// RUN: clang-tidy %t.cpp -checks='-*,google-explicit-constructor,llvm-namespace-comment' -fix -- > %t.msg 2>&1
+// RUN: clang-tidy %t.cpp -checks='-*,google-explicit-constructor,llvm-namespace-comment' -fix -export-fixes=%t.yaml -- > %t.msg 2>&1
 // RUN: FileCheck -input-file=%t.cpp %s
 // RUN: FileCheck -input-file=%t.msg -check-prefix=CHECK-MESSAGES %s
+// RUN: FileCheck -input-file=%t.yaml -check-prefix=CHECK-YAML %s
 
 namespace i {
 }
 // CHECK: } // namespace i
 // CHECK-MESSAGES: note: FIX-IT applied suggested code changes
+// CHECK-YAML: ReplacementText: ' // namespace i'
 
 class A { A(int i); };
 // CHECK: class A { explicit A(int i); };
 // CHECK-MESSAGES: note: FIX-IT applied suggested code changes
 // CHECK-MESSAGES: clang-tidy applied 2 of 2 suggested fixes.
+// CHECK-YAML: ReplacementText: 'explicit '