[GR-28227] Backport: Java null should behave like null during Object creation.

PullRequest: js/1820

Author: iamstolis

graal-js/src/com.oracle.truffle.js.test/js/interop/javaNull.js

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2020, 2020, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * Licensed under the Universal Permissive License v 1.0 as shown at http://oss.oracle.com/licenses/upl.
+ */
+
+load('../assert.js');
+
+var javaNull = java.lang.System.getProperty("iDontExist");
+
+assertSame(Object.prototype, Object.getPrototypeOf(Object(javaNull)));
+assertSame(Object.prototype, Object.getPrototypeOf(new Object(javaNull)));
+assertSame(null, Object.getPrototypeOf(Object.create(javaNull)));
+
+true;

graal-js/src/com.oracle.truffle.js.test/src/com/oracle/truffle/js/test/interop/ForeignBoxedObjectTest.java

@@ -57,7 +57,9 @@ public class ForeignBoxedObjectTest {
     public void testForeignNull() {
         try (Context context = JSTest.newContextBuilder().build()) {
             context.getBindings("js").putMember("obj", new ForeignNull());
-            assertTrue(context.eval(ID, "try { Object(obj); false; } catch (e) { e instanceof TypeError }").asBoolean());
+            assertTrue(context.eval(ID, "Object.getPrototypeOf(Object(obj)) === Object.prototype").asBoolean());
+            assertTrue(context.eval(ID, "Object.getPrototypeOf(new Object(obj)) === Object.prototype").asBoolean());
+            assertTrue(context.eval(ID, "Object.getPrototypeOf(Object.create(obj)) === null").asBoolean());
             assertTrue(context.eval(ID, "try { obj.foo; false; } catch (e) { e instanceof TypeError }").asBoolean());
             assertTrue(context.eval(ID, "try { obj.foo(); false; } catch (e) { e instanceof TypeError }").asBoolean());
         }

graal-js/src/com.oracle.truffle.js/src/com/oracle/truffle/js/builtins/ConstructorBuiltins.java

@@ -1393,6 +1393,7 @@ protected DynamicObject getIntrinsicDefaultProto(JSRealm realm) {
 
     }
 
+    @ImportStatic({JSConfig.class})
     public abstract static class ConstructObjectNode extends ConstructWithNewTargetNode {
         public ConstructObjectNode(JSContext context, JSBuiltin builtin, boolean isNewTargetCase) {
             super(context, builtin, isNewTargetCase);
@@ -1403,6 +1404,10 @@ protected static boolean arg0NullOrUndefined(Object[] args) {
             return (arg0 == Undefined.instance) || (arg0 == Null.instance);
         }
 
+        protected static Object firstArgument(Object[] arguments) {
+            return (arguments.length == 0) ? Undefined.instance : arguments[0];
+        }
+
         @Specialization(guards = {"isNewTargetCase"})
         protected DynamicObject constructObjectNewTarget(DynamicObject newTarget, @SuppressWarnings("unused") Object[] arguments) {
             return newObject(newTarget);
@@ -1413,10 +1418,17 @@ protected DynamicObject constructObject0(DynamicObject newTarget, @SuppressWarni
             return newObject(newTarget);
         }
 
-        @Specialization(guards = {"!isNewTargetCase", "arguments.length > 0", "!arg0NullOrUndefined(arguments)"})
+        @Specialization(guards = {"!isNewTargetCase", "arguments.length > 0", "!arg0NullOrUndefined(arguments)"}, limit = "InteropLibraryLimit")
         protected Object constructObjectJSObject(@SuppressWarnings("unused") DynamicObject newTarget, Object[] arguments,
-                        @Cached("createToObject(getContext())") JSToObjectNode toObjectNode) {
-            return toObjectNode.execute(arguments[0]);
+                        @Cached("createToObject(getContext())") JSToObjectNode toObjectNode,
+                        @CachedLibrary("firstArgument(arguments)") InteropLibrary interop,
+                        @Cached("createBinaryProfile()") ConditionProfile isNull) {
+            Object arg0 = arguments[0];
+            if (isNull.profile(interop.isNull(arg0))) {
+                return newObject(Null.instance);
+            } else {
+                return toObjectNode.execute(arg0);
+            }
         }
 
         @Specialization(guards = {"arguments.length > 0", "arg0NullOrUndefined(arguments)"})

graal-js/src/com.oracle.truffle.js/src/com/oracle/truffle/js/builtins/ObjectFunctionBuiltins.java

@@ -581,6 +581,7 @@ protected DynamicObject intlDefineProperties(DynamicObject obj, DynamicObject de
         }
     }
 
+    @ImportStatic({JSConfig.class})
     public abstract static class ObjectCreateNode extends ObjectDefineOperation {
         public ObjectCreateNode(JSContext context, JSBuiltin builtin) {
             super(context, builtin);
@@ -596,12 +597,16 @@ protected DynamicObject createPrototypeNull(Object prototype, Object properties)
             return objectDefineProperties(ret, properties);
         }
 
-        @TruffleBoundary
-        @SuppressWarnings("unused")
-        @Specialization(guards = {"!isJSNull(prototype)", "!isJSObject(prototype)"})
-        protected DynamicObject createInvalidPrototype(Object prototype, Object properties) {
+        @Specialization(guards = {"!isJSNull(prototype)", "!isJSObject(prototype)"}, limit = "InteropLibraryLimit")
+        protected DynamicObject createForeignNullOrInvalidPrototype(Object prototype, Object properties,
+                        @CachedLibrary("prototype") InteropLibrary interop,
+                        @Cached("createBinaryProfile()") ConditionProfile isNull) {
             assert prototype != null;
-            throw Errors.createTypeErrorInvalidPrototype(prototype);
+            if (isNull.profile(prototype != Undefined.instance && interop.isNull(prototype))) {
+                return createPrototypeNull(Null.instance, properties);
+            } else {
+                throw Errors.createTypeErrorInvalidPrototype(prototype);
+            }
         }
 
         @Specialization(guards = {"isJSObject(prototype)", "isJSObject(properties)"})