migrator: ensure we update unresolved member access correctly to global names. rdar://41658300

Author: nkcsgexi

include/swift/IDE/APIDigesterData.h

@@ -276,7 +276,7 @@ struct TypeMemberDiffItem: public APIDiffItem {
     selfIndex(selfIndex), removedIndex(removedIndex), oldTypeName(oldTypeName),
     oldPrintedName(oldPrintedName), OldNameViewer(oldPrintedName),
     NewNameViewer(newPrintedName),
-    NewTypeDot(newTypeName.empty() ? "" : (llvm::Twine(newTypeName) + ".").str()),
+    NewTypeDot(isNewNameGlobal() ? "" : (llvm::Twine(newTypeName) + ".").str()),
     Subkind(getSubKind()) {}
   static StringRef head();
   static void describe(llvm::raw_ostream &os);
@@ -291,6 +291,7 @@ struct TypeMemberDiffItem: public APIDiffItem {
   APIDiffItemKind getKind() const override {
     return APIDiffItemKind::ADK_TypeMemberDiffItem;
   }
+  bool isNewNameGlobal() const { return newTypeName.empty(); }
 private:
   TypeMemberDiffItemSubKind getSubKind() const;
 };

lib/Migrator/APIDiffMigratorPass.cpp

@@ -343,8 +343,13 @@ struct APIDiffMigratorPass : public ASTMigratorPass, public SourceEntityWalker {
       if (MD->Subkind == TypeMemberDiffItemSubKind::SimpleReplacement) {
         bool NeedNoTypeName = isDotMember &&
           MD->oldPrintedName == MD->newPrintedName;
-        Text = (llvm::Twine(NeedNoTypeName ? "." : MD->getNewTypeAndDot()) +
-          MD->getNewName().base()).str();
+        if (NeedNoTypeName) {
+          Text = (llvm::Twine(MD->isNewNameGlobal() ? "" : ".") +
+            MD->getNewName().base()).str();
+        } else {
+          Text = (llvm::Twine(MD->getNewTypeAndDot()) +
+            MD->getNewName().base()).str();
+        }
         return true;
       }
     }
@@ -540,9 +545,15 @@ struct APIDiffMigratorPass : public ASTMigratorPass, public SourceEntityWalker {
           if (Item->Subkind == TypeMemberDiffItemSubKind::QualifiedReplacement) {
             bool NeedNoTypeName = isDotMember(ToReplace) &&
               Item->oldPrintedName == Item->newPrintedName;
-            Editor.replace(ToReplace,
-              (llvm::Twine(NeedNoTypeName ? "." : Item->getNewTypeAndDot()) +
-               Item->getNewName().base()).str());
+            if (NeedNoTypeName) {
+              Editor.replace(ToReplace,
+                (llvm::Twine(Item->isNewNameGlobal() ? "" : ".") +
+                Item->getNewName().base()).str());
+            } else {
+              Editor.replace(ToReplace,
+                (llvm::Twine(Item->getNewTypeAndDot()) +
+                  Item->getNewName().base()).str());
+            }
             return true;
           }
         }

test/Migrator/Inputs/qualified.json

@@ -55,4 +55,12 @@
     "NewPrintedName": "orderedMemberSame",
     "NewTypeName": "NewFooComparisonResult.Nested"
   },
+  {
+    "DiffItemKind": "TypeMemberDiffItem",
+    "Usr": "c:@E@FooComparisonResult@FooOrderedMovedToGlobal",
+    "OldPrintedName": "orderedMovedToGlobal",
+    "OldTypeName": "FooComparisonResult",
+    "NewPrintedName": "orderedMovedToGlobal",
+    "NewTypeName": ""
+  },
 ]

test/Migrator/mock-sdk/Bar.framework/Headers/Bar.h

@@ -55,6 +55,7 @@ typedef NS_ENUM(long, FooComparisonResult) {
   FooOrderedSame,
   FooOrderedDescending,
   FooOrderedMemberSame,
+  FooOrderedMovedToGlobal,
 };
 
 @interface BarBase

test/Migrator/qualified-replacement.swift

@@ -19,6 +19,8 @@ func foo() {
   bar(.orderedMemberSame)
   bar(FooComparisonResult.orderedSame)
   bar(FooComparisonResult.orderedMemberSame)
+  bar(FooComparisonResult.orderedMovedToGlobal)
+  bar(.orderedMovedToGlobal)
 }
 
 func foo(_: ToplevelType) {}

test/Migrator/qualified-replacement.swift.expected

@@ -19,6 +19,8 @@ func foo() {
   bar(.orderedMemberSame)
   bar(NewFooComparisonResult.NewFooOrderedSame)
   bar(NewFooComparisonResult.Nested.orderedMemberSame)
+  bar(orderedMovedToGlobal)
+  bar(orderedMovedToGlobal)
 }
 
 func foo(_: ToplevelWrapper.internalType) {}