Implement Array.prototype's copyWithin method (#3269)

The algorithm is based on ECMA-262 v6, 22.1.3.3

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

tests/jerry/es2015/array-prototype-copywithin.js

@@ -0,0 +1,81 @@
+// 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.
+
+var obj = {};
+
+// Checking behavior with normal inputs
+var array = ["foo", 1, "bar", obj, 2, "baz"];
+assert(array.copyWithin(2,0,6).toString() === "foo,1,foo,1,bar,[object Object]");
+assert(array.copyWithin(0,1,3).toString() === "1,foo,foo,1,bar,[object Object]");
+assert(array.copyWithin(3,0,4).toString() === "1,foo,foo,1,foo,foo");
+
+// Checking behavior with default inputs
+var array = ["foo", 1, "bar", obj, 2, "baz"];
+assert(array.copyWithin().toString() === "foo,1,bar,[object Object],2,baz");
+assert(array.copyWithin(2).toString() === "foo,1,foo,1,bar,[object Object]");
+assert(array.copyWithin(1,4).toString() === "foo,bar,[object Object],1,bar,[object Object]");
+
+// Checking behavior when argument is negative or bigger then length
+var array = ["foo", 1, "bar", obj, 2, "baz"];
+assert(array.copyWithin(12,3,-3).toString() === "foo,1,bar,[object Object],2,baz");
+assert(array.copyWithin(-2,-4,3).toString() === "foo,1,bar,[object Object],bar,baz");
+assert(array.copyWithin(1,-5,30).toString() === "foo,1,bar,[object Object],bar,baz");
+
+// Checking behavior with undefined, NaN, +/- Infinity
+var array = ["foo", 1, "bar", obj, 2, "baz"];
+assert(array.copyWithin(undefined).toString() === "foo,1,bar,[object Object],2,baz");
+assert(array.copyWithin(2, NaN).toString()=== "foo,1,foo,1,bar,[object Object]");
+assert(array.copyWithin(2,undefined,5).toString() === "foo,1,foo,1,foo,1");
+
+var array = ["foo", 1, "bar", obj, 2, "baz"];
+assert(array.copyWithin(Infinity,2,NaN).toString() === "foo,1,bar,[object Object],2,baz");
+assert(array.copyWithin(Infinity,-Infinity,4).toString()=== "foo,1,bar,[object Object],2,baz");
+assert(array.copyWithin(NaN,0,3).toString() === "foo,1,bar,[object Object],2,baz");
+
+// Checking behavior when no length property defined
+var obj = { copyWithin : Array.prototype.copyWithin };
+
+obj.copyWithin();
+assert(obj.length === undefined);
+
+// Checking behavior when unable to get length
+var obj = { copyWithin : Array.prototype.copyWithin };
+Object.defineProperty(obj, 'length', { 'get' : function () {throw new ReferenceError ("foo"); } });
+
+try {
+  obj.copyWithin(1);
+  assert(false)
+} catch (e) {
+  assert(e.message === "foo");
+  assert(e instanceof ReferenceError);
+}
+
+// Checking behavior when unable to get element
+var obj = { copyWithin : Array.prototype.copyWithin, length : 5 };
+Object.defineProperty(obj, '2', { 'get' : function () {throw new ReferenceError ("foo"); } });
+
+try {
+  obj.copyWithin(2);
+  assert(false);
+} catch (e) {
+  assert(e.message === "foo");
+  assert(e instanceof ReferenceError);
+}
+
+// Checking behavior when a property is not defined
+var obj = { '0' : 2, '2' : "foo", length : 3, copyWithin : Array.prototype.copyWithin };
+
+obj.copyWithin(1);
+assert(obj[0] === 2);
+assert(obj[1] === 2);