Partially fix semantics of Array.push()

test/mjsunit/array-push4.js

Index: test/mjsunit/array-push4.js
diff --git a/test/mjsunit/array-push4.js b/test/mjsunit/array-push4.js
new file mode 100644
index 0000000000000000000000000000000000000000..678873fb3afce974cfdfbc9986d62cf97273d33f
--- /dev/null
+++ b/test/mjsunit/array-push4.js
@@ -0,0 +1,60 @@
+// 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.
+
+// Flags: --allow-natives-syntax
+
+var v = 0;
+var my_array_proto = {};
+my_array_proto.__proto__ = [].__proto__;
+Object.defineProperty(my_array_proto, "0", {
+get: function() { return "get " + v; },
+set: function(value) { v += value; }
+});
+
+
+// Test that element accessors are called in standard push cases.
+array = [];
+array.__proto__ = my_array_proto;
+
+array[0] = 10;
+assertEquals(0, array.length);
+assertEquals(10, v);
+assertEquals("get 10", array[0]);
+
+Array.prototype.push.call(array, 100);
+assertEquals(1, array.length);
+assertEquals(110, v);
+assertEquals("get 110", array[0]);
+
+array = [];
+array.__proto__ = my_array_proto;
+
+assertEquals(0, array.length);
+array.push(110);
+assertEquals(1, array.length);
+assertEquals(220, v);
+assertEquals("get 220", array[0]);
+
+// Test that elements setters/getters on prototype chain are property detected
+// and don't lead to overzealous optimization.
+v = 0;
+function push_wrapper_1(array, value) {
+  array.push(value);
+}
+array = [];
+array.__proto__ = my_array_proto;
+push_wrapper_1(array, 100);
+assertEquals(1, array.length);
+assertEquals(100, v);
+push_wrapper_1(array, 100);
+assertEquals(2, array.length);
+assertEquals(100, v);
+assertEquals("get 100", array[0]);
+%OptimizeFunctionOnNextCall(push_wrapper_1);
+array = [];
+array.__proto__ = my_array_proto;
+push_wrapper_1(array, 100);
+assertEquals(1, array.length);
+assertEquals(200, v);
+assertEquals("get 200", array[0]);