Implement IsConstructor() abstract operation

test/mjsunit/harmony/array-of.js

 // Copyright 2014 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.
 
 // Based on Mozilla Array.of() tests at http://dxr.mozilla.org/mozilla-central/source/js/src/jit-test/tests/collections
 
 // Flags: --harmony-arrays
 
 
 
@@ skipping 141 matching lines @@
 
 var desc = Object.getOwnPropertyDescriptor(Array, "of");
 
 assertEquals(desc.configurable, true);
 assertEquals(desc.enumerable, false);
 assertEquals(desc.writable, true);
 assertEquals(Array.of.length, 0);
 assertThrows(function() { new Array.of() }, TypeError);  // not a constructor
 
 // When the this-value passed in is not a constructor, the result is an array.
-[undefined, null, false, "cow"].forEach(function(val) {
-    assertEquals(Array.isArray(Array.of(val)), true);
+[
+  undefined,
+  null,
+  false,
+  "cow",
+  NaN,
+  67,
+  Infinity,
+  -Infinity,
+  Math.cos, // builtin functions with no [[Construct]] slot
+  Math.cos.bind(Math) // bound builtin functions with no [[Construct]] slot
+].forEach(function(val) {
+    assertEquals(Array.isArray(Array.of.call(val, val)), true);
 });
+
+
+(function testBoundConstructor() {
+  var boundFn = (function() {}).bind(null);
+  var instance = Array.of.call(boundFn, 1, 2, 3);
+  assertEquals(instance.length, 3);
+  assertEquals(instance instanceof boundFn, true);
+  assertEquals(Array.isArray(instance), false);
+})();