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import { add } from './add.js'import { converge } from './converge.js'import { multiply } from './multiply.js'
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)).toBe(161)})
test('passes the results of applying the arguments individually', () => {  const result = converge(multiply)([ add(1), add(3) ])(2)  expect(result).toBe(15)})
test('returns a function with the length of the longest argument', () => {  expect(f1).toHaveLength(1)  expect(f2).toHaveLength(2)  expect(f3).toHaveLength(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)).toBe(2)  expect(b.call(context, 1)).toBe(3)  expect(d.call(context, 1)).toBe(5)})
test('works with empty functions list', () => {  const fn = converge(function (){    return arguments.length  }, [])  expect(fn).toHaveLength(0)  expect(fn()).toBe(0)})