Add support for computed property names in object literals

test/mjsunit/object-literal-computed-names.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.
+
+// Test computed properties syntax.
+
+// Flags: --harmony-symbols
+
+function assertObjectEquals(expected, actual) {
+    var expected_props = Object.getOwnPropertyNames(expected);
+    var actual_props = Object.getOwnPropertyNames(actual);
+    expected_props += Object.getOwnPropertySymbols(expected);
+    actual_props += Object.getOwnPropertySymbols(actual);
+
+    assertEquals(expected_props.length, actual_props.length);
+    for (var i = 0; i < expected_props.length; i++) {
+        var prop = expected_props[i];
+        assertEquals(prop, actual_props[i]);
+        assertEquals(expected[prop], actual[prop]);
+    }
+}
+
+function preparse(str, strict) {
+    // Trigger the preparser by fooling it into thinking that the
+    // function is really big.
+    var buffer = '/* ' + (' ' * 4096) + '*/';

[arv (Not doing code reviews), 2014/06/11 19:28:29]

(' ' * 4096)

This doesn't do what you think it does.

Do this instead,

Array(4096 + 1).join(' ')

or --harmony_strings and ' '.repeat(4096)

+    var body = (strict ? '"use strict"; ' : '') + 'return ' + buffer + str;
+    return Function(body)();
+}
+
+function parse(str, strict) {
+    var indirect_eval = eval;
+    var body = (strict ? '"use strict"; ' : '') + '(' + str + ')';
+    return indirect_eval(body);
+}
+
+function test(expected, str) {
+    assertObjectEquals(expected, parse(str, true));
+    assertObjectEquals(expected, parse(str, false));
+    assertObjectEquals(expected, preparse(str, true));
+    assertObjectEquals(expected, preparse(str, false));
+}
+
+var sym = Symbol();
+var expected_with_sym = {};
+expected_with_sym[sym] = 'ohai';
+

[arv (Not doing code reviews), 2014/06/11 19:28:29]

Can you also add a test that ensures that a computed property name that computes
to "__proto__" does not set the [[Prototype]]?

var a = 42;
var b = {['__proto__']: a};
assertEquals(Object.getPrototypeOf(b), Object.prototype);
assertEquals(b.__proto__, a);
assertTrue(b.hasOwnProperty('__proto__'));

https://people.mozilla.org/~jorendorff/es6-draft.html#sec-__proto__-property-...

+test({foo: 42},          "{['foo']: 42}");
+test({foo: 10},          "{['foo']: 42, foo: 10}");
+test({foo: 42},          "{foo: 10, ['foo']: 42}");
+test({foo: 42, bar: 35}, "{foo: 10, ['foo']: 42, bar: 35}");
+test({foo: 42, bar: 35}, "{foo: 10, bar: 35, ['foo']: 42}");
+test({bar: 35, foo: 42}, "{bar: 35, foo: 10, ['foo']: 42}");
+test({bar: 35, foo: 10}, "{bar: 35, ['foo']: 42, foo: 10}");
+test({bar: 35, foo: 10}, "{['bar']: 35, ['foo']: 42, foo: 10}");
+test({bar: 35, foo: 42}, "{['bar']: 35, foo: 10, ['foo']: 42}");
+test({foo: 42},          "{foo: 10, [1 ? 'foo' : 'bar']: 42}");
+test({foo: 10, bar: 42}, "{foo: 10, [0 ? 'foo' : 'bar']: 42}");
+test(expected_with_sym,  "{[sym]: 'ohai'}");
+test(expected_with_sym,  "{[1 ? sym : 'foo']: 'ohai'}");
+test({foo: 'ohai'},      "{[0 ? sym : 'foo']: 'ohai'}");