Merge pull request #4197 from nkcsgexi/migrator-fixit

[FixCode] Blacklist the fixit for enum case renames for migrator

Author: tkremenek

lib/FrontendTool/FrontendTool.cpp

@@ -613,6 +613,10 @@ class JSONFixitWriter : public DiagnosticConsumer {
     // invalidating some inits with type errors.
     if (Info.ID == diag::init_not_instance_member.ID)
       return false;
+    // Renaming enum cases interacts poorly with the swift migrator by
+    // reverting changes made by the mgirator.
+    if (Info.ID == diag::could_not_find_enum_case.ID)
+      return false;
 
     if (Kind == DiagnosticKind::Error)
       return true;

test/FixCode/fixits-apply.swift

@@ -221,3 +221,8 @@ protocol Prot2 {
 }
 class Cls1 : Prot1 {}
 func testwhere<T: Prot2 where T.Ty == Cls1>(_: T) {}
+
+enum E {
+  case abc
+}
+func testEnumRename() { _ = E.Abc }

test/FixCode/fixits-apply.swift.result

@@ -224,3 +224,8 @@ protocol Prot2 {
 }
 class Cls1 : Prot1 {}
 func testwhere<T: Prot2>(_: T) where T.Ty == Cls1 {}
+
+enum E {
+  case abc
+}
+func testEnumRename() { _ = E.Abc }