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/**
* Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
'use strict';
var Symbol = global['jest-symbol-do-not-touch'] || global.Symbol;
var Symbol = global['jest-symbol-do-not-touch'] || global.Symbol;
var Promise = global[Symbol.for('jest-native-promise')] || global.Promise;
class CancelError extends Error {
constructor() {
super('Promise was canceled');
this.name = 'CancelError';
}
}
class PCancelable {
static fn(fn) {
return function() {
const args = [].slice.apply(arguments);
return new PCancelable((onCancel, resolve, reject) => {
args.unshift(onCancel);
fn.apply(null, args).then(resolve, reject);
});
};
}
constructor(executor) {
this._pending = true;
this._canceled = false;
this._promise = new Promise((resolve, reject) => {
this._reject = reject;
return executor(
fn => {
this._cancel = fn;
},
val => {
this._pending = false;
resolve(val);
},
err => {
this._pending = false;
reject(err);
}
);
});
}
then() {
return this._promise.then.apply(this._promise, arguments);
}
catch() {
return this._promise.catch.apply(this._promise, arguments);
}
cancel() {
if (!this._pending || this._canceled) {
return;
}
if (typeof this._cancel === 'function') {
try {
this._cancel();
} catch (err) {
this._reject(err);
}
}
this._canceled = true;
this._reject(new CancelError());
}
get canceled() {
return this._canceled;
}
}
Object.setPrototypeOf(PCancelable.prototype, Promise.prototype);
module.exports = PCancelable;
module.exports.CancelError = CancelError;