Reflection: add KClass.isInstance, KClass.cast, KClass.safeCast

#KT-11284 Fixed

compiler/testData/codegen/box/reflection/isInstance/isInstanceCastAndSafeCast.kt

@@ -0,0 +1,58 @@
+// WITH_REFLECT
+
+import kotlin.reflect.KClass
+import kotlin.reflect.cast
+import kotlin.reflect.safeCast
+import kotlin.test.*
+
+fun testInstance(value: Any?, klass: KClass<*>) {
+    assertTrue(klass.isInstance(value))
+    assertEquals(value, klass.safeCast(value))
+    assertEquals(value, klass.cast(value))
+}
+
+fun testNotInstance(value: Any?, klass: KClass<*>) {
+    assertFalse(klass.isInstance(value))
+    assertNull(klass.safeCast(value))
+    try {
+        klass.cast(value)
+        fail("Value should not be an instance of $klass: $value")
+    }
+    catch (e: Exception) { /* OK */ }
+}
+
+fun box(): String {
+    testInstance(Any(), Any::class)
+    testInstance("", String::class)
+    testInstance("", Any::class)
+    testNotInstance(Any(), String::class)
+    testNotInstance(null, Any::class)
+    testNotInstance(null, String::class)
+
+    testInstance(arrayOf(""), Array<String>::class)
+    testInstance(arrayOf(""), Array<Any>::class)
+    testNotInstance(arrayOf(Any()), Array<String>::class)
+
+    testInstance(listOf(""), List::class)
+    testInstance(listOf(""), Collection::class)
+    // TODO: support MutableList::class (KT-11754)
+    // testNotInstance(listOf(""), MutableList::class)
+
+    testInstance(42, Int::class)
+    testInstance(42, Int::class.javaPrimitiveType!!.kotlin)
+    testInstance(42, Int::class.javaObjectType!!.kotlin)
+
+    testNotInstance(3.14, Int::class)
+
+    // Function types
+
+    testInstance(fun() {}, Function0::class)
+    testNotInstance(fun() {}, Function1::class)
+    testNotInstance(fun() {}, Function2::class)
+
+    testNotInstance(::testInstance, Function0::class)
+    testNotInstance(::testInstance, Function1::class)
+    testInstance(::testInstance, Function2::class)
+
+    return "OK"
+}

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -12235,6 +12235,21 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             }
         }
 
+        @TestMetadata("compiler/testData/codegen/box/reflection/isInstance")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class IsInstance extends AbstractBlackBoxCodegenTest {
+            public void testAllFilesPresentInIsInstance() throws Exception {
+                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/reflection/isInstance"), Pattern.compile("^(.+)\\.kt$"), true);
+            }
+
+            @TestMetadata("isInstanceCastAndSafeCast.kt")
+            public void testIsInstanceCastAndSafeCast() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/box/reflection/isInstance/isInstanceCastAndSafeCast.kt");
+                doTest(fileName);
+            }
+        }
+
         @TestMetadata("compiler/testData/codegen/box/reflection/kClassInAnnotation")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)