Throw the right exceptions from setting elements in Array.prototype.concat

test/mjsunit/regress/regress-595319.js

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://bugs.chromium.org/p/chromium/issues/detail?id=595319
+// Ensure exceptions are checked for by Array.prototype.concat from adding
+// an element, and that elements are added to array subclasses appropraitely

[adamk, 2016/03/17 19:22:21]

Typo: s/appropraitely/appropriately/

[Dan Ehrenberg, 2016/03/17 20:26:33]

Done

+
+// If adding a property does throw, the exception is propagated
+class MyException extends Error { }
+class MyArray extends Array {
+  constructor(...args) {
+    super(...args);
+    return new Proxy(this, {
+      defineProperty() { throw new MyException(); }
+    });
+  }
+}
+assertThrows(() => new MyArray().concat([1]), MyException);
+
+// Ensure elements are added to the instance, rather than calling [[Set]].
+Object.prototype.__defineGetter__(0, function(){});
+class MyArray2 extends Array { };
+Array.prototype.constructor = MyArray2;
+assertArrayEquals([0.5], [].concat(0.5));