react-native/local-cli/link/__tests__/promiseWaterfall.spec.js

49 lines
1.2 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* All rights reserved.
*
* @emails oncall+javascript_foundation
*/
'use strict';
const sinon = require('sinon');
const promiseWaterfall = require('../promiseWaterfall');
describe('promiseWaterfall', () => {
it('should run promises in a sequence', (done) => {
const tasks = [sinon.stub(), sinon.stub()];
promiseWaterfall(tasks).then(() => {
expect(tasks[0].calledBefore(tasks[1])).toBeTruthy();
done();
});
});
it('should resolve with last promise value', (done) => {
const tasks = [sinon.stub().returns(1), sinon.stub().returns(2)];
promiseWaterfall(tasks).then(value => {
expect(value).toEqual(2);
done();
});
});
it('should stop the sequence when one of promises is rejected', (done) => {
const error = new Error();
const tasks = [sinon.stub().throws(error), sinon.stub().returns(2)];
promiseWaterfall(tasks).catch(err => {
expect(err).toEqual(error);
expect(tasks[1].callCount).toEqual(0);
done();
});
});
});