v8/test/mjsunit/es6/regexp-flags.js
littledan b22b258874 ES2015 web compat workaround: RegExp.prototype.flags => ""
It turns out that some old polyfill library uses
RegExp.prototype.flags as a way of feature testing. It's not clear
how widespread this is. For now, as a minimal workaround, we can
return undefined from getters like RegExp.prototype.global when
the receiver is RegExp.prototype. This patch implements that strategy
but omits a UseCounter to make backports easier.

R=adamk
CC=yangguo@chromium.org
BUG=chromium:581577
LOG=Y
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1640803003

Cr-Commit-Position: refs/heads/master@{#34201}
2016-02-23 01:49:03 +00:00

67 lines
2.0 KiB
JavaScript

// Copyright 2015 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: --harmony-regexps --harmony-unicode-regexps
var r1 = /abc/gi;
assertEquals("abc", r1.source);
assertTrue(r1.global);
assertTrue(r1.ignoreCase);
assertFalse(r1.multiline);
assertFalse(r1.sticky);
assertFalse(r1.unicode);
// Internal slot of prototype is not read.
var r2 = { __proto__: r1 };
assertThrows(function() { r2.source; }, TypeError);
assertThrows(function() { r2.global; }, TypeError);
assertThrows(function() { r2.ignoreCase; }, TypeError);
assertThrows(function() { r2.multiline; }, TypeError);
assertThrows(function() { r2.sticky; }, TypeError);
assertThrows(function() { r2.unicode; }, TypeError);
var r3 = /I/;
var string = "iIiIi";
var expected = "iXiIi";
assertFalse(r3.global);
assertFalse(r3.ignoreCase);
assertEquals("", r3.flags);
assertEquals(expected, string.replace(r3, "X"));
var get_count = 0;
Object.defineProperty(r3, "global", {
get: function() { get_count++; return true; }
});
Object.defineProperty(r3, "ignoreCase", {
get: function() { get_count++; return true; }
});
assertTrue(r3.global);
assertEquals(1, get_count);
assertTrue(r3.ignoreCase);
assertEquals(2, get_count);
// Overridden flag getters affects the flags getter.
assertEquals("gi", r3.flags);
assertEquals(4, get_count);
// Overridden flag getters do not affect the internal flags.
assertEquals(expected, string.replace(r3, "X"));
assertEquals(4, get_count);
function testName(name) {
// TODO(littledan): For web compatibility, we don't throw an exception,
// but ES2015 expects an exception to be thrown from this getter.
assertEquals(undefined, RegExp.prototype[name]);
assertEquals(
"get " + name,
Object.getOwnPropertyDescriptor(RegExp.prototype, name).get.name);
}
testName("global");
testName("ignoreCase");
testName("multiline");
testName("source");
testName("sticky");
testName("unicode");