FE: add test for KT-53197

compiler/testData/diagnostics/tests/override/InternalPotentialOverride.fir.kt

@@ -0,0 +1,21 @@
+// MODULE: m1
+// FILE: A.kt
+
+open class A {
+    internal open fun foo() : Int = 1
+}
+
+open class AG<T> {
+    internal open fun bar(arg: T) = arg
+}
+
+// MODULE: m2(m1)
+// FILE: B.kt
+
+class B : A() {
+    fun <!VIRTUAL_MEMBER_HIDDEN!>foo<!>() : String = ""
+}
+
+class BG : AG<String>() {
+    fun bar(arg: Int) = arg
+}

compiler/testData/diagnostics/tests/override/InternalPotentialOverride.kt

@@ -0,0 +1,21 @@
+// MODULE: m1
+// FILE: A.kt
+
+open class A {
+    internal open fun foo() : Int = 1
+}
+
+open class AG<T> {
+    internal open fun bar(arg: T) = arg
+}
+
+// MODULE: m2(m1)
+// FILE: B.kt
+
+class B : A() {
+    fun foo() : String = ""
+}
+
+class BG : AG<String>() {
+    fun bar(arg: Int) = arg
+}

compiler/testData/diagnostics/tests/override/InternalPotentialOverride.txt

@@ -0,0 +1,39 @@
+// -- Module: <m1> --
+package
+
+public open class A {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    internal open fun foo(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class AG</*0*/ T> {
+    public constructor AG</*0*/ T>()
+    internal open fun bar(/*0*/ arg: T): T
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+// -- Module: <m2> --
+package
+
+public final class B : A {
+    public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final fun foo(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class BG : AG<kotlin.String> {
+    public constructor BG()
+    public final fun bar(/*0*/ arg: kotlin.Int): kotlin.Int
+    invisible_fake open override /*1*/ /*fake_override*/ fun bar(/*0*/ arg: kotlin.String): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+