import {add} from './add'import {converge} from './converge'import {multiply} from './multiply'
const f1 = converge(multiply, [a => a + 1, a => a + 10])const f2 = converge(multiply, [a => a + 1, (a, b) => a + b + 10])const f3 = converge(multiply, [a => a + 1, (a, b, c) => a + b + c + 10])
test('happy', () => { expect(f2(6, 7)).toEqual(161)})
test('passes the results of applying the arguments individually', () => { const result = converge(multiply)([add(1), add(3)])(2) expect(result).toEqual(15)})
test('returns a function with the length of the longest argument', () => { expect(f1.length).toEqual(1) expect(f2.length).toEqual(2) expect(f3.length).toEqual(3)})
test('passes context to its functions', () => { const a = function (x) { return this.f1(x) } const b = function (x) { return this.f2(x) } const c = function (x, y) { return this.f3(x, y) } const d = converge(c, [a, b]) const context = { f1: add(1), f2: add(2), f3: add, } expect(a.call(context, 1)).toEqual(2) expect(b.call(context, 1)).toEqual(3) expect(d.call(context, 1)).toEqual(5)})
test('works with empty functions list', () => { const fn = converge(function () { return arguments.length }, []) expect(fn.length).toEqual(0) expect(fn()).toEqual(0)})