v8/test/mjsunit/regexp-string-methods.js
littledan 92a571e546 Add ES2015 RegExp full subclassing semantics behind a flag
This patch implements ES2015 RegExp subclassing semantics, namely the
hardest part where RegExp.prototype.exec and certain flag getters can
be overridden in order to provide different behavior. This change is
hidden behind a new flag, --harmony-regexp-exec. The flag guards the
behavior by installing entirely different implementations of the
methods which follow the new semantics.

Preliminary performance tests show a 3-4x regression in the Octane
RegExp benchmark. The new code doesn't call out into several fast
paths that the old code supported, so this is expected.

The patch is tested mostly by test262, where most RegExp tests are fixed,
with the exception of deliberate spec violations for web compatibility,
and for the 'sticky' flag, which is not dynamically read by this patch
in all cases but rather statically compiled into the RegExp. The latter
will require a follow-on patch to implement. A small additional set of
tests verifies one particular case, mostly to check whether the flag
mechanism works.

R=adamk,yangguo@chromium.org
LOG=Y
BUG=v8:4602

Review URL: https://codereview.chromium.org/1596483005

Cr-Commit-Position: refs/heads/master@{#35068}
2016-03-24 22:27:21 +00:00

54 lines
2.5 KiB
JavaScript

// Copyright 2009 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: --no-harmony-regexp-exec
// Regexp shouldn't use String.prototype.slice()
var s = new String("foo");
assertEquals("f", s.slice(0,1));
String.prototype.slice = function() { return "x"; };
assertEquals("x", s.slice(0,1));
assertEquals(["g"], /g/.exec("gg"));
// Regexp shouldn't use String.prototype.charAt()
var f1 = new RegExp("f", "i");
assertEquals(["F"], f1.exec("F"));
assertEquals("f", "foo".charAt(0));
String.prototype.charAt = function(idx) { return 'g'; };
assertEquals("g", "foo".charAt(0));
var f2 = new RegExp("[g]", "i");
assertEquals(["G"], f2.exec("G"));
assertTrue(f2.ignoreCase);
// On the other hand test is defined in a semi-coherent way as a call to exec.
// 15.10.6.3
// We match other browsers in using the original value of RegExp.prototype.exec.
// I.e., RegExp.prototype.test shouldn't use the current value of
// RegExp.prototype.exec.
RegExp.prototype.exec = function(string) { return 'x'; };
assertFalse(/f/.test('x'));