13 lines
459 B
JavaScript
13 lines
459 B
JavaScript
const expect = require('expect');
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const {differenceBy} = require('./_30s.js');
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test('differenceBy is a Function', () => {
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expect(differenceBy).toBeInstanceOf(Function);
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});
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test('Works using a native function and numbers', () => {
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expect(differenceBy([2.1, 1.2], [2.3, 3.4], Math.floor)).toEqual([1.2]);
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});
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test('Works with arrow function and objects', () => {
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expect(differenceBy([{ x: 2 }, { x: 1 }], [{ x: 1 }], v => v.x)).toEqual([{ x: 2 }]);
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});
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