Added tests on class delegation

backend.native/tests/build.gradle

@@ -556,6 +556,26 @@ task bridges_test16(type: RunKonanTest) {
     source = "codegen/bridges/test16.kt"
 }
 
+task classDelegation_method(type: RunKonanTest) {
+    goldValue = "OKOK\n"
+    source = "codegen/classDelegation/method.kt"
+}
+
+task classDelegation_property(type: RunKonanTest) {
+    goldValue = "4242\n"
+    source = "codegen/classDelegation/property.kt"
+}
+
+task classDelegation_generic(type: RunKonanTest) {
+    goldValue = "OK\n"
+    source = "codegen/classDelegation/generic.kt"
+}
+
+task classDelegation_withBridge(type: RunKonanTest) {
+    goldValue = "OK\n"
+    source = "codegen/classDelegation/withBridge.kt"
+}
+
 task array0(type: RunKonanTest) {
     goldValue = "5\n6\n7\n8\n9\n10\n11\n12\n13\n"
     source = "runtime/collections/array0.kt"

backend.native/tests/codegen/classDelegation/generic.kt

@@ -0,0 +1,21 @@
+open class Content() {
+    override fun toString() = "OK"
+}
+
+interface Box<E> {
+    fun get(): E
+}
+
+interface ContentBox<T : Content> : Box<T>
+
+object Impl : ContentBox<Content> {
+    override fun get(): Content = Content()
+}
+
+class ContentBoxDelegate<T : Content>() : ContentBox<T> by (Impl as ContentBox<T>)
+
+fun box() = ContentBoxDelegate<Content>().get().toString()
+
+fun main(args: Array<String>) {
+    println(box())
+}

backend.native/tests/codegen/classDelegation/method.kt

@@ -0,0 +1,19 @@
+interface A<T> {
+    fun foo(): T
+}
+
+class B : A<String> {
+    override fun foo() = "OK"
+}
+
+class C(a: A<String>) : A<String> by a
+
+fun box(): String {
+    val c = C(B())
+    val a: A<String> = c
+    return c.foo() + a.foo()
+}
+
+fun main(args: Array<String>) {
+    println(box())
+}

backend.native/tests/codegen/classDelegation/property.kt

@@ -0,0 +1,19 @@
+interface A {
+    val x: Int
+}
+
+class C: A {
+    override val x: Int = 42
+}
+
+class Q(a: A): A by a
+
+fun box(): String {
+    val q = Q(C())
+    val a: A = q
+    return q.x.toString() + a.x.toString()
+}
+
+fun main(args: Array<String>) {
+    println(box())
+}

backend.native/tests/codegen/classDelegation/withBridge.kt

@@ -0,0 +1,28 @@
+interface A<T> {
+    fun foo(t: T): String
+}
+
+interface B {
+    fun foo(t: Int) = "B"
+}
+
+class Z : B
+
+class Z1 : A<Int>, B by Z()
+
+fun box(): String {
+    val z1 = Z1()
+    val z1a: A<Int> = z1
+    val z1b: B = z1
+
+    return when {
+        z1.foo( 0)  != "B" -> "Fail #1"
+        z1a.foo( 0) != "B" -> "Fail #2"
+        z1b.foo( 0) != "B" -> "Fail #3"
+        else -> "OK"
+    }
+}
+
+fun main(args: Array<String>) {
+    println(box())
+}