KJS: allow to use KClass::isInstance; implement isInstance in KClassImpl

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/AbstractReflectionApiCallChecker.kt

@@ -29,6 +29,8 @@ import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.storage.getValue
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
+private val ANY_MEMBER_NAMES = setOf("equals", "hashCode", "toString")
+
 /**
  * Checks that there are no usages of reflection API which will fail at runtime.
  */
@@ -41,8 +43,6 @@ abstract class AbstractReflectionApiCallChecker(private val module: ModuleDescri
         setOf(reflectionTypes.kProperty0, reflectionTypes.kProperty1, reflectionTypes.kProperty2)
     }
 
-    private val ANY_MEMBER_NAMES = setOf("equals", "hashCode", "toString")
-
     final override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
         if (isWholeReflectionApiAvailable) return
 

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/diagnostics/JsReflectionAPICallChecker.kt

@@ -28,6 +28,8 @@ import org.jetbrains.kotlin.resolve.calls.checkers.CallCheckerContext
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.storage.getValue
 
+private val ALLOWED_KCLASS_MEMBERS = setOf("simpleName", "isInstance")
+
 class JsReflectionAPICallChecker(private val module: ModuleDescriptor, storageManager: StorageManager) : AbstractReflectionApiCallChecker(module, storageManager) {
     override val isWholeReflectionApiAvailable: Boolean
         get() = false
@@ -40,5 +42,5 @@ class JsReflectionAPICallChecker(private val module: ModuleDescriptor, storageMa
 
     override fun isAllowedReflectionApi(descriptor: CallableDescriptor, containingClass: ClassDescriptor): Boolean =
             super.isAllowedReflectionApi(descriptor, containingClass) ||
-            DescriptorUtils.isSubclass(containingClass, kClass) && descriptor.name.asString() == "simpleName"
+            DescriptorUtils.isSubclass(containingClass, kClass) && descriptor.name.asString() in ALLOWED_KCLASS_MEMBERS
 }

js/js.libraries/src/reflect/KClassImpl.kt

@@ -71,7 +71,7 @@ internal class KClassImpl<T : Any>(
     }
 
     override fun isInstance(value: Any?): Boolean {
-        TODO()
+        return js("Kotlin").isType(value, jClass)
     }
 
     override fun toString(): String {

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/BoxJsTestGenerated.java

@@ -6259,6 +6259,12 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("kClassIsInstance.kt")
+        public void testKClassIsInstance() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/reflection/kClassIsInstance.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("kClassOnReifiedType.kt")
         public void testKClassOnReifiedType() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/reflection/kClassOnReifiedType.kt");

js/js.translator/testData/box/reflection/kClassIsInstance.kt

@@ -0,0 +1,22 @@
+package foo
+
+import kotlin.reflect.KClass
+
+fun <A : Any, B : A> check(k: KClass<A>, instance: B, nonInstance: Any) {
+    assertTrue(k.isInstance(instance))
+    assertFalse(k.isInstance(nonInstance))
+    assertFalse(k.isInstance(null))
+}
+
+fun box(): String {
+    check(A::class, A(), O)
+    check(A::class, B(), O)
+    check(O::class, O, object {})
+    check(I::class, object : I {}, object {})
+    check(E::class, E.X, A())
+    check(E::class, E.Y, B())
+    check(E::class, E.Z, O)
+    check(E.Y::class, E.Y, E.X)
+
+    return "OK"
+}

js/js.translator/testData/box/reflection/kClassSimpleName.kt

@@ -12,6 +12,7 @@ fun testWithInstance() {
     assertEquals("A", A()::class.simpleName)
     assertEquals("B", B()::class.simpleName)
     assertEquals("O", (O)::class.simpleName)
+    assertEquals("Q", R()::class.simpleName)
     assertEquals("E", E.X::class.simpleName)
     assertEquals("Y", E.Y::class.simpleName)
 // TODO uncomment after KT-13338 is fixed
@@ -26,6 +27,7 @@ fun testWithClassReference() {
     assertEquals("B", B::class.simpleName)
     assertEquals("O", O::class.simpleName)
     assertEquals("I", I::class.simpleName)
+    assertEquals("Q", R::class.simpleName)
     assertEquals("E", E::class.simpleName)
     assertEquals("undefined", foo.undefined::class.simpleName)
     assertEquals("Nested", Outer.Nested::class.simpleName)

js/js.translator/testData/box/reflection/kClassToAndFromJsClass.kt

@@ -19,6 +19,7 @@ fun box(): String {
     check(B::class, jsClassbyName("B"))
     check(O::class, jsClassbyName("O").constructor)
     check(I::class, jsClassbyName("I"))
+    check(R::class, jsClassbyName("Q"))
     check(E::class, jsClassbyName("E"))
     check(E.X::class, jsClassbyName("E").X.constructor)
     check(E.Y::class, jsClassbyName("E").Y.constructor)