Merge pull request #4239 from jrose-apple/swift-3-PrintAsObjC-existential-metatypes-are-metatypes-too

[PrintAsObjC] Handle forward-declarations for 'Class <SomeProto>'.

Author: tkremenek

lib/PrintAsObjC/PrintAsObjC.cpp

@@ -1560,7 +1560,7 @@ class ReferencedTypeFinder : private TypeVisitor<ReferencedTypeFinder> {
     Callback(*this, nominal->getDecl());
   }
 
-  void visitMetatypeType(MetatypeType *metatype) {
+  void visitAnyMetatypeType(AnyMetatypeType *metatype) {
     visit(metatype->getInstanceType());
   }
 

test/PrintAsObjC/classes.swift

@@ -328,6 +328,18 @@ class MyObject : NSObject {}
 // CHECK-NEXT: @end
 @objc protocol MyProtocol : NSObjectProtocol {}
 
+// CHECK-LABEL: @protocol MyProtocolMetaOnly;
+// CHECK-LABEL: @interface MyProtocolMetaCheck
+// CHECK-NEXT: - (void)test:(Class <MyProtocolMetaOnly> _Nullable)x;
+// CHECK-NEXT: init
+// CHECK-NEXT: @end
+@objc class MyProtocolMetaCheck {
+  func test(_ x: MyProtocolMetaOnly.Type?) {}
+}
+// CHECK-LABEL: @protocol MyProtocolMetaOnly
+// CHECK-NEXT: @end
+@objc protocol MyProtocolMetaOnly {}
+
 // CHECK-LABEL: @interface Nested
 // CHECK-NEXT: init
 // CHECK-NEXT: @end

test/PrintAsObjC/extensions.swift

@@ -12,6 +12,7 @@
 
 import Foundation
 import AppKit
+import objc_generics
 
 // CHECK-NOT: AppKit
 
@@ -83,6 +84,13 @@ extension CGColor {
   func anyOldMethod() {}
 }
 
+// CHECK-LABEL: @interface GenericClass (SWIFT_EXTENSION(extensions))
+// CHECK-NEXT: - (void)bar;
+// CHECK-NEXT: @end
+extension GenericClass {
+  func bar() {}
+}
+
 // NEGATIVE-NOT: NotObjC
 class NotObjC {}
 extension NotObjC {}