Proper treatment of return types

compiler/testData/diagnostics/tests/j+k/types/returnCollection.kt

@@ -0,0 +1,13 @@
+// FILE: k.kt
+
+trait K {
+    fun foo(): List<String>
+}
+
+// FILE: J.java
+
+import java.util.*;
+
+interface J extends K {
+    List<String> foo();
+}

compiler/testData/diagnostics/tests/j+k/types/returnCollection.txt

@@ -0,0 +1,17 @@
+package
+
+public/*package*/ /*synthesized*/ fun J(/*0*/ function: () -> kotlin.(Mutable)List<kotlin.String!>!): J
+
+public/*package*/ trait J : K {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract override /*1*/ fun foo(): kotlin.List<kotlin.String>
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal trait K {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    internal abstract fun foo(): kotlin.List<kotlin.String>
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/j+k/types/shapeMismatchInCovariantPosition.kt

@@ -0,0 +1,19 @@
+// FILE: k.kt
+
+trait G<T>
+trait SubG : G<String>
+
+trait K {
+    fun foo(): G<String>
+    fun bar(): G<String>?
+}
+
+// FILE: J.java
+
+import java.util.*;
+
+interface J extends K {
+    SubG foo();
+    SubG bar();
+    SubG baz();
+}

compiler/testData/diagnostics/tests/j+k/types/shapeMismatchInCovariantPosition.txt

@@ -0,0 +1,30 @@
+package
+
+internal trait G</*0*/ 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
+}
+
+public/*package*/ trait J : K {
+    public abstract override /*1*/ fun bar(): SubG?
+    public abstract fun baz(): SubG!
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract override /*1*/ fun foo(): SubG
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal trait K {
+    internal abstract fun bar(): G<kotlin.String>?
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    internal abstract fun foo(): G<kotlin.String>
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal trait SubG : G<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
+}

compiler/testData/diagnostics/tests/j+k/types/shapeMismatchInCovariantPositionGeneric.kt

@@ -0,0 +1,19 @@
+// FILE: k.kt
+
+trait G<T>
+trait SubG<A, B> : G<String>
+
+trait K<KT> {
+    fun foo(): G<KT>
+    fun bar(): G<KT>?
+}
+
+// FILE: J.java
+
+import java.util.*;
+
+interface J extends K<String> {
+    SubG<String, G<String>> foo();
+    SubG<String, G<String>> bar();
+    SubG<String, G<String>> baz();
+}

compiler/testData/diagnostics/tests/j+k/types/shapeMismatchInCovariantPositionGeneric.txt

@@ -0,0 +1,30 @@
+package
+
+internal trait G</*0*/ 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
+}
+
+public/*package*/ trait J : K<kotlin.String!> {
+    public abstract override /*1*/ fun bar(): SubG<kotlin.String!, G<kotlin.String!>!>?
+    public abstract fun baz(): SubG<kotlin.String!, G<kotlin.String!>!>!
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract override /*1*/ fun foo(): SubG<kotlin.String!, G<kotlin.String!>!>
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal trait K</*0*/ KT> {
+    internal abstract fun bar(): G<KT>?
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    internal abstract fun foo(): G<KT>
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal trait SubG</*0*/ A, /*1*/ B> : G<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
+}