From 7c28a2e7323876b1556e1d800b3001087b50df11 Mon Sep 17 00:00:00 2001
From: Alexander Udalov <Alexander.Udalov@jetbrains.com>
Date: Tue, 25 Aug 2015 12:40:56 +0300
Subject: [PATCH] Support KClass.defaultType

---
 .../reflection/classes/defaultType.kt         | 25 +++++++++++++++++++
 ...lackBoxWithStdlibCodegenTestGenerated.java |  6 +++++
 .../src/kotlin/reflect/KClassExtensions.kt    |  9 +++++++
 3 files changed, 40 insertions(+)
 create mode 100644 compiler/testData/codegen/boxWithStdlib/reflection/classes/defaultType.kt

diff --git a/compiler/testData/codegen/boxWithStdlib/reflection/classes/defaultType.kt b/compiler/testData/codegen/boxWithStdlib/reflection/classes/defaultType.kt
new file mode 100644
index 00000000000..e99f3463744
--- /dev/null
+++ b/compiler/testData/codegen/boxWithStdlib/reflection/classes/defaultType.kt
@@ -0,0 +1,25 @@
+import kotlin.reflect.defaultType
+import kotlin.reflect.jvm.javaType
+import kotlin.test.assertEquals
+import kotlin.test.assertNotEquals
+
+class Simple
+class Generic<K, V> {
+    fun thiz() = this
+}
+
+fun simple() = Simple()
+fun genericIntString() = Generic<Int, String>()
+
+fun box(): String {
+    assertEquals(javaClass<Simple>(), Simple::class.defaultType.javaType)
+    assertEquals(::simple.returnType, Simple::class.defaultType)
+
+    assertEquals(javaClass<Generic<*, *>>(), Generic::class.defaultType.javaType)
+    assertEquals(Generic<*, *>::thiz.returnType, Generic::class.defaultType)
+
+    // Generic<Int, String> != Generic<K, V>
+    assertNotEquals(::genericIntString.returnType, Generic::class.defaultType)
+
+    return "OK"
+}
diff --git a/compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java b/compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java
index a88db02fb82..010ffa0c704 100644
--- a/compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java
+++ b/compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithStdlibCodegenTestGenerated.java
@@ -3012,6 +3012,12 @@ public class BlackBoxWithStdlibCodegenTestGenerated extends AbstractBlackBoxCode
                 doTestWithStdlib(fileName);
             }
 
+            @TestMetadata("defaultType.kt")
+            public void testDefaultType() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/reflection/classes/defaultType.kt");
+                doTestWithStdlib(fileName);
+            }
+
             @TestMetadata("jvmName.kt")
             public void testJvmName() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/boxWithStdlib/reflection/classes/jvmName.kt");
diff --git a/core/reflection.jvm/src/kotlin/reflect/KClassExtensions.kt b/core/reflection.jvm/src/kotlin/reflect/KClassExtensions.kt
index f84643f8ec9..a4a2ec24650 100644
--- a/core/reflection.jvm/src/kotlin/reflect/KClassExtensions.kt
+++ b/core/reflection.jvm/src/kotlin/reflect/KClassExtensions.kt
@@ -19,6 +19,7 @@ package kotlin.reflect
 import org.jetbrains.kotlin.descriptors.ConstructorDescriptor
 import kotlin.reflect.jvm.internal.KClassImpl
 import kotlin.reflect.jvm.internal.KFunctionImpl
+import kotlin.reflect.jvm.internal.KTypeImpl
 
 /**
  * Returns the primary constructor of this class, or `null` if this class has no primary constructor.
@@ -30,6 +31,14 @@ public val <T : Any> KClass<T>.primaryConstructor: KFunction<T>?
         ((it as KFunctionImpl).descriptor as ConstructorDescriptor).isPrimary
     }
 
+/**
+ * Returns a type corresponding to the given class with type parameters of that class substituted as the corresponding arguments.
+ * For example, for class `MyMap<K, V>` [defaultType] would return the type `MyMap<K, V>`.
+ */
+public val KClass<*>.defaultType: KType
+    get() = KTypeImpl((this as KClassImpl<*>).descriptor.defaultType) { jClass }
+
+
 /**
  * Returns static functions declared in this class.
  */