Add regression test to close #43135

Author: AnthonyLatsis

test/stdlib/Inputs/Mirror/Mirror.h

@@ -27,4 +27,7 @@
 @interface FooMoreDerivedObjCClass : FooDerivedObjCClass
 @end
 
+@interface StringConvertibleInDebugAndOtherwise_ObjC : NSObject
+@end
+
 #endif

test/stdlib/Inputs/Mirror/Mirror.mm

@@ -31,3 +31,14 @@ @implementation FooDerivedObjCClass : FooObjCClass
 @implementation FooMoreDerivedObjCClass : FooDerivedObjCClass
 @end
 
+@implementation StringConvertibleInDebugAndOtherwise_ObjC : NSObject
+
+-(NSString *) description {
+  return @"description";
+}
+
+-(NSString *) debugDescription {
+  return @"debugDescription";
+}
+
+@end

test/stdlib/RuntimeObjC.swift

@@ -740,14 +740,17 @@ Reflection.test("Name of metatype of artificial subclass") {
   expectEqual(String(reflecting: type(of: obj)), "a.TestArtificialSubclass")
 }
 
-@objc class StringConvertibleInDebugAndOtherwise : NSObject {
+@objc class StringConvertibleInDebugAndOtherwise_Native : NSObject {
   override var description: String { return "description" }
   override var debugDescription: String { return "debugDescription" }
 }
 
 Reflection.test("NSObject is properly CustomDebugStringConvertible") {
-  let object = StringConvertibleInDebugAndOtherwise()
-  expectEqual(String(reflecting: object), object.debugDescription)
+  let objectNative = StringConvertibleInDebugAndOtherwise_Native()
+  let objectObjC = StringConvertibleInDebugAndOtherwise_ObjC()
+
+  expectEqual(String(reflecting: objectNative), objectNative.debugDescription)
+  expectEqual(String(reflecting: objectObjC), objectObjC.debugDescription)
 }
 
 Reflection.test("NSRange QuickLook") {