Add test for https://github.com/JetBrains/kotlin-native/issues/3992

backend.native/tests/objcexport/expectedLazy.h

@@ -348,6 +348,39 @@ __attribute__((swift_name("TestIncompatiblePropertyTypeWarning.ClassOverridingIn
 @property (readonly) KtTestIncompatiblePropertyTypeWarningGeneric<NSString *> *p __attribute__((swift_name("p")));
 @end;
 
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("TestGH3992")))
+@interface KtTestGH3992 : KtBase
+- (instancetype)init __attribute__((swift_name("init()"))) __attribute__((objc_designated_initializer));
++ (instancetype)new __attribute__((availability(swift, unavailable, message="use object initializers instead")));
+@end;
+
+__attribute__((swift_name("TestGH3992.C")))
+@interface KtTestGH3992C : KtBase
+- (instancetype)initWithA:(KtTestGH3992A *)a __attribute__((swift_name("init(a:)"))) __attribute__((objc_designated_initializer));
+@property (readonly) KtTestGH3992A *a __attribute__((swift_name("a")));
+@end;
+
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("TestGH3992.D")))
+@interface KtTestGH3992D : KtTestGH3992C
+- (instancetype)initWithA:(KtTestGH3992B *)a __attribute__((swift_name("init(a:)"))) __attribute__((objc_designated_initializer));
+@property (readonly) KtTestGH3992B *a __attribute__((swift_name("a")));
+@end;
+
+__attribute__((swift_name("TestGH3992.A")))
+@interface KtTestGH3992A : KtBase
+- (instancetype)init __attribute__((swift_name("init()"))) __attribute__((objc_designated_initializer));
++ (instancetype)new __attribute__((availability(swift, unavailable, message="use object initializers instead")));
+@end;
+
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("TestGH3992.B")))
+@interface KtTestGH3992B : KtTestGH3992A
+- (instancetype)init __attribute__((swift_name("init()"))) __attribute__((objc_designated_initializer));
++ (instancetype)new __attribute__((availability(swift, unavailable, message="use object initializers instead")));
+@end;
+
 __attribute__((objc_subclassing_restricted))
 __attribute__((swift_name("Kt35940Kt")))
 @interface KtKt35940Kt : KtBase

backend.native/tests/objcexport/headerWarnings.kt

@@ -16,3 +16,14 @@ class TestIncompatiblePropertyTypeWarning {
 
     class ClassOverridingInterfaceWithGenericProperty(override val p: Generic<String>) : InterfaceWithGenericProperty<String>
 }
+
+// https://github.com/JetBrains/kotlin-native/issues/3992
+class TestGH3992 {
+    abstract class C(open val a: A)
+
+    class D(override val a: B) : C(a)
+
+    abstract class A
+
+    class B : A()
+}

backend.native/tests/objcexport/headerWarnings.swift

@@ -22,10 +22,21 @@ private func testIncompatiblePropertyType() throws {
     try assertEquals(actual: pi.value as! String, expected: "cba")
 }
 
+private func testGH3992() throws {
+    let d = TestGH3992.D(a: TestGH3992.B())
+    let c: TestGH3992.C = d
+
+    let b: TestGH3992.B = d.a
+    let a: TestGH3992.A = b
+
+    try assertTrue(a is TestGH3992.B)
+}
+
 class HeaderWarningsTests : SimpleTestProvider {
     override init() {
         super.init()
 
         test("TestIncompatiblePropertyType", testIncompatiblePropertyType)
+        test("TestGH3992", testGH3992)
     }
 }