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// Copyright 2016 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.
var log = [];
var fake =
{
get source() {
log.push("p");
return {
toString: function() {
log.push("ps");
return "pattern";
}
};
},
get flags() {
log.push("f");
return {
toString: function() {
log.push("fs");
return "flags";
}
};
}
}
function testThrows(x) {
try {
RegExp.prototype.toString.call(x);
} catch (e) {
assertTrue(/incompatible receiver/.test(e.message));
return;
}
assertUnreachable();
}
testThrows(1);
testThrows(null);
Number.prototype.source = "a";
Number.prototype.flags = "b";
testThrows(1);
assertEquals("/pattern/flags", RegExp.prototype.toString.call(fake));
assertEquals(["p", "ps", "f", "fs"], log);
// Monkey-patching is also possible on RegExp instances
let weird = /foo/;
Object.defineProperty(weird, 'flags', {value: 'bar'});
Object.defineProperty(weird, 'source', {value: 'baz'});
assertEquals('/baz/bar', weird.toString());
assertEquals('/(?:)/', RegExp.prototype.toString());
assertEquals('(?:)', RegExp.prototype.source);
assertEquals('', RegExp.prototype.flags);
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