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

#KT-11284 Fixed
2016-07-12 18:48:37 +03:00
parent 3702f4a7a7
commit ada81923dc
7 changed files with 136 additions and 3 deletions
@@ -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"
+}