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// Copyright (C) 2017 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-assertion
description: Do not backtrack into a lookbehind.
info: |
The production Assertion :: (?<=Disjunction) evaluates as follows:
1. Evaluate Disjunction with -1 as its direction argument to obtain a Matcher m.
2. Return an internal Matcher closure that takes two arguments, a State x and a Continuation
c, and performs the following steps:
a. Let d be a Continuation that always returns its State argument as a successful MatchResult.
b. Call m(x, d) and let r be its result.
c. If r is failure, return failure.
d. Let y be r's State.
e. Let cap be y's captures List.
f. Let xe be x's endIndex.
g. Let z be the State (xe, cap).
h. Call c(z) and return its result.
features: [regexp-lookbehind]
---*/
// The lookbehind captures "abc" so that \1 does not match. We do not backtrack
// to capture only "bc" in the lookbehind.
assert.sameValue("abcdbc".match(/(?<=([abc]+)).\1/), null);
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