import lodashStable from 'lodash'; import { falsey, args, slice, symbol, realm } from './utils'; import isBoolean from '../src/isBoolean'; describe('isBoolean', () => { it('should return `true` for booleans', () => { expect(isBoolean(true)).toBe(true); expect(isBoolean(false)).toBe(true); expect(isBoolean(Object(true))).toBe(true); expect(isBoolean(Object(false))).toBe(true); }); it('should return `false` for non-booleans', () => { const expected = lodashStable.map(falsey, (value) => value === false); const actual = lodashStable.map(falsey, (value, index) => index ? isBoolean(value) : isBoolean(), ); expect(actual).toEqual(expected); expect(isBoolean(args)).toBe(false); expect(isBoolean([1, 2, 3])).toBe(false); expect(isBoolean(new Date())).toBe(false); expect(isBoolean(new Error())).toBe(false); expect(isBoolean(slice)).toBe(false); expect(isBoolean({ a: 1 })).toBe(false); expect(isBoolean(1)).toBe(false); expect(isBoolean(/x/)).toBe(false); expect(isBoolean('a')).toBe(false); expect(isBoolean(symbol)).toBe(false); }); it('should work with a boolean from another realm', () => { if (realm.boolean) { expect(isBoolean(realm.boolean)).toBe(true); } }); });