Fix bug 344: always keep attributes of existing properties.

test/mjsunit/bugs/bug-334.js

-// Copyright 2008 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// Flags: --allow-natives-syntax
-
-// Test for http://code.google.com/p/v8/issues/detail?id=334
-
-var READ_ONLY   = 1;
-var DONT_ENUM   = 2;
-var DONT_DELETE = 4;
-
-function func1(){}
-function func2(){}
-
-var object = {__proto__:{}};
-%SetProperty(object, "foo", func1, DONT_ENUM | DONT_DELETE);
-%SetProperty(object, "bar", func1, DONT_ENUM | READ_ONLY);
-%SetProperty(object, "baz", func1, DONT_DELETE | READ_ONLY);
-%SetProperty(object.__proto__, "bif", func1, DONT_ENUM | DONT_DELETE | READ_ONLY);
-object.bif = func2;
-
-function enumerable(obj) {
-  var res = [];
-  for (var i in obj) {
-    res.push(i);
-  }
-  res.sort();
-  return res;
-}
-
-// Sanity check: expected initial state.
-assertArrayEquals(["baz", "bif"], enumerable(object), "enum0");
-assertFalse(delete object.foo, "delete foo");
-assertFalse(delete object.baz, "delete baz");
-assertEquals(func1, object.foo, "read foo");
-assertEquals(func1, object.bar, "read bar");
-assertEquals(func1, object.baz, "read baz");
-assertEquals(func2, object.bif, "read bif");
-
-// Can't assign to READ_ONLY.
-object.bar = "NO WAY";
-assertEquals(func1, object.bar, "read bar 2");
-assertArrayEquals(["baz", "bif"], enumerable(object), "enum1");
-
-// Assignment to non-readonly. Assignment shouldn't change attributes!
-object.foo = func2;
-assertArrayEquals(["baz", "bif"], enumerable(object), "enum2");
-assertFalse(delete object.foo, "delete foo 2");
-
-// Delete should erase attributes if value set again.
-assertTrue(delete object.bar, "delete bar");
-assertFalse("bar" in object, "has bar");
-object.bar = func2;
-assertTrue("bar" in object, "has bar 2");
-assertEquals(func2, object.bar, "read bar 3");
-
-assertArrayEquals(["bar", "baz", "bif"], enumerable(object), "enum3");
-
-// Unshadowing a prototype property exposes its attributes.
-assertTrue(delete object.bif, "delete bif");
-assertArrayEquals(["bar", "baz"], enumerable(object), "enum4");
-assertEquals(func1, object.bif, "read bif 2");
-// Can't delete prototype property.
-assertTrue(delete object.bif, "delete bif 2");
-assertArrayEquals(["bar", "baz"], enumerable(object), "enum5");
-assertEquals(func1, object.bif, "read bif3");