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// deno-fmt-ignore-file// deno-lint-ignore-file
// Copyright Joyent and Node contributors. All rights reserved. MIT license.// Taken from Node 18.12.0// This file is automatically generated by "node/_tools/setup.ts". Do not modify this file manually
// Copyright Joyent, Inc. and other Node contributors.//// Permission is hereby granted, free of charge, to any person obtaining a// copy of this software and associated documentation files (the// "Software"), to deal in the Software without restriction, including// without limitation the rights to use, copy, modify, merge, publish,// distribute, sublicense, and/or sell copies of the Software, and to permit// persons to whom the Software is furnished to do so, subject to the// following conditions://// The above copyright notice and this permission notice shall be included// in all copies or substantial portions of the Software.//// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';const common = require('../common');const assert = require('assert');const EventEmitter = require('events');
const e = new EventEmitter();
e.once('hello', common.mustCall());
e.emit('hello', 'a', 'b');e.emit('hello', 'a', 'b');e.emit('hello', 'a', 'b');e.emit('hello', 'a', 'b');
function remove() {  assert.fail('once->foo should not be emitted');}
e.once('foo', remove);e.removeListener('foo', remove);e.emit('foo');
e.once('e', common.mustCall(function() {  e.emit('e');}));
e.once('e', common.mustCall());
e.emit('e');
{  // once() has different code paths based on the number of arguments being  // emitted. Verify that all of the cases are covered.  const maxArgs = 4;
  for (let i = 0; i <= maxArgs; ++i) {    const ee = new EventEmitter();    const args = ['foo'];
    for (let j = 0; j < i; ++j)      args.push(j);
    ee.once('foo', common.mustCall((...params) => {      assert.deepStrictEqual(params, args.slice(1));    }));
    EventEmitter.prototype.emit.apply(ee, args);  }}