Add option to list symbols in Object.getOwnPropertyNames() (#3507)

Also a little refactoring of Object.getOwnPropertyNames()

JerryScript-DCO-1.0-Signed-off-by: Peter Marki marpeter@inf.u-szeged.hu

tests/jerry/es2015/object-assign.js

@@ -156,3 +156,12 @@ try {
 } catch (e) {
   assert (e instanceof TypeError)
 }
+
+var asd = Symbol ("asd");
+var foo = Symbol ("foo");
+var bar = Symbol ("bar");
+var obj = {1: 5, "a": 6, [foo]: 7, [asd]: 8, [bar]: 9};
+var result = Object.assign ({}, obj);
+assert (result[foo] == 7);
+assert (result[asd] == 8);
+assert (result[bar] == 9);

tests/jerry/es2015/object-get-own-property-names.js

@@ -0,0 +1,23 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Check that Object.getOwnPropertyNames does NOT include Symbols by default.
+var asd = Symbol ("asd");
+var foo = Symbol ("foo");
+var bar = Symbol ("bar");
+var result = Object.getOwnPropertyNames ({1: 5, "a": 6, [foo]: 7, [asd]: 8, [bar]: 9});
+assert (!Object.hasOwnProperty (result, foo));
+assert (!Object.hasOwnProperty (result, asd));
+assert (!Object.hasOwnProperty (result, bar));