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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-regular-expressions-patterns
es6id: B.1.4
description: Quantifiable assertions `?!` ("not followed by")
info: |
Term[U] ::
[~U] QuantifiableAssertion Quantifier
QuantifiableAssertion::
( ?= Disjunction )
( ?! Disjunction )
The production Term::QuantifiableAssertionQuantifier evaluates the same as
the production Term::AtomQuantifier but with QuantifiableAssertion
substituted for Atom.
The production Assertion::QuantifiableAssertion evaluates by evaluating
QuantifiableAssertion to obtain a Matcher and returning that Matcher.
Assertion (21.2.2.6) evaluation rules for the Assertion::(?=Disjunction)
and Assertion::(?!Disjunction) productions are also used for the
QuantifiableAssertion productions, but with QuantifiableAssertion
substituted for Assertion.
---*/
var match;
match = /[a-e](?!Z)*/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'a', 'quantifier: *');
match = /[a-e](?!Z)+/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: +');
match = /[a-e](?!Z)?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'a', 'quantifier: ?');
match = /[a-e](?!Z){2}/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: { DecimalDigits }');
match = /[a-e](?!Z){2,}/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: { DecimalDigits , }');
match = /[a-e](?!Z){2,3}/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(
match[0], 'e', 'quantifier: { DecimalDigits , DecimalDigits }'
);
match = /[a-e](?!Z)*?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'a', 'quantifier: * ?');
match = /[a-e](?!Z)+?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: + ?');
match = /[a-e](?!Z)??/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'a', 'quantifier: ? ?');
match = /[a-e](?!Z){2}?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: { DecimalDigits } ?');
match = /[a-e](?!Z){2,}?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(match[0], 'e', 'quantifier: { DecimalDigits , } ?');
match = /[a-e](?!Z){2,3}?/.exec('aZZZZ bZZZ cZZ dZ e');
assert.sameValue(
match[0], 'e', 'quantifier: { DecimalDigits , DecimalDigits } ?'
);
reportCompare(0, 0);