* chore: make aware eslint that we use jest By setting up the jest environment, we no longer need to declare the 'test' global in the configuration. * chore: don't need to import expect, it's a jest environment global * chore: don't need to import expect when creating undefined test
19 lines
532 B
JavaScript
19 lines
532 B
JavaScript
const {shuffle} = require('./_30s.js');
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test('shuffle is a Function', () => {
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expect(shuffle).toBeInstanceOf(Function);
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});
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const arr = [1, 2, 3, 4, 5, 6];
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test('Shuffles the array', () => {
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expect(shuffle(arr)).not.toEqual(arr);
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});
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test('New array contains all original elements', () => {
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expect(shuffle(arr).every(x => arr.includes(x))).toBeTruthy();
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});
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test('Works for empty arrays', () => {
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expect(shuffle([])).toEqual([]);
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});
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test('Works for single-element arrays', () => {
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expect(shuffle([1])).toEqual([1]);
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});
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