react-native/Libraries/Utilities/__tests__/groupByEveryN-test.js

41 lines
1.3 KiB
JavaScript

/**
* Copyright (c) 2013-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
*/
'use strict';
jest.unmock('groupByEveryN');
describe('groupByEveryN', () => {
var groupByEveryN = require('groupByEveryN');
it ('should group by with different n', () => {
expect(groupByEveryN([1, 2, 3, 4, 5, 6, 7, 8, 9], 1))
.toEqual([[1], [2], [3], [4], [5], [6], [7], [8], [9]]);
expect(groupByEveryN([1, 2, 3, 4, 5, 6, 7, 8, 9], 2))
.toEqual([[1, 2], [3, 4], [5, 6], [7, 8], [9, null]]);
expect(groupByEveryN([1, 2, 3, 4, 5, 6, 7, 8, 9], 3))
.toEqual([[1, 2, 3], [4, 5, 6], [7, 8, 9]]);
expect(groupByEveryN([1, 2, 3, 4, 5, 6, 7, 8, 9], 4))
.toEqual([[1, 2, 3, 4], [5, 6, 7, 8], [9, null, null, null]]);
});
it ('should fill with null', () => {
expect(groupByEveryN([], 4))
.toEqual([]);
expect(groupByEveryN([1], 4))
.toEqual([[1, null, null, null]]);
expect(groupByEveryN([1, 2], 4))
.toEqual([[1, 2, null, null]]);
expect(groupByEveryN([1, 2, 3], 4))
.toEqual([[1, 2, 3, null]]);
expect(groupByEveryN([1, 2, 3, 4], 4))
.toEqual([[1, 2, 3, 4]]);
});
});