import lodashStable from 'lodash'; import { identity, empties, stubFalse, stubTrue } from './utils'; import some from '../src/some'; describe('some', () => { it('should return `true` if `predicate` returns truthy for any element', () => { expect(some([false, 1, ''], identity)).toBe(true); expect(some([null, 'a', 0], identity)).toBe(true); }); it('should return `false` for empty collections', () => { const expected = lodashStable.map(empties, stubFalse); const actual = lodashStable.map(empties, (value) => { try { return some(value, identity); } catch (e) {} }); expect(actual).toEqual(expected); }); it('should return `true` as soon as `predicate` returns truthy', () => { let count = 0; expect( some([null, true, null], (value) => { count++; return value; }) ); expect(count).toBe(2); }); it('should return `false` if `predicate` returns falsey for all elements', () => { expect(some([false, false, false], identity)).toBe(false); expect(some([null, 0, ''], identity)).toBe(false); }); it('should use `_.identity` when `predicate` is nullish', () => { const values = [, null, undefined]; let expected = lodashStable.map(values, stubFalse); let actual = lodashStable.map(values, (value, index) => { const array = [0, 0]; return index ? some(array, value) : some(array); }); expect(actual).toEqual(expected); expected = lodashStable.map(values, stubTrue); actual = lodashStable.map(values, (value, index) => { const array = [0, 1]; return index ? some(array, value) : some(array); }); expect(actual).toEqual(expected); }); it('should work with `_.property` shorthands', () => { const objects = [ { a: 0, b: 0 }, { a: 0, b: 1 }, ]; expect(some(objects, 'a')).toBe(false); expect(some(objects, 'b')).toBe(true); }); it('should work with `_.matches` shorthands', () => { const objects = [ { a: 0, b: 0 }, { a: 1, b: 1 }, ]; expect(some(objects, { a: 0 })).toBe(true); expect(some(objects, { b: 2 })).toBe(false); }); it('should work as an iteratee for methods like `_.map`', () => { const actual = lodashStable.map([[1]], some); expect(actual).toEqual([true]); }); });