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import { always, identity, inc, isNil, map, modulo, multiply } from 'rambdax'import { composeWith as composeWithRamda, concat, flip, ifElse } from 'ramda'
import { composeWith } from './composeWith.js'
test('performs right-to-left function composition with function applying', () => {  const f = composeWith((f, res) => f(res))([ map, multiply, parseInt ])
  expect(f).toHaveLength(2)  expect(f('10')([ 1, 2, 3 ])).toEqual([ 10, 20, 30 ])  expect(f('10', 2)([ 1, 2, 3 ])).toEqual([ 2, 4, 6 ])})
test('performs right-to-left function while not nil result', () => {  const isOdd = flip(modulo)(2)  const composeWhenNotNil = composeWithRamda((f, res) =>    isNil(res) ? null : f(res))
  const f = composeWhenNotNil([    inc,    ifElse(      isOdd, identity, always(null)    ),    parseInt,  ])  expect(f).toHaveLength(2)  expect(f('1')).toBe(2)  expect(f('2')).toBeNull()})
test('performs right-to-left function using promise chaining', () => {  const then = function (f, p){    return p.then(f)  }  const composeP = composeWithRamda(then)  const toListPromise = function (a){    return new Promise(res => {      res([ a ])    })  }  const doubleListPromise = function (a){    return new Promise(res => {      res(concat(a, a))    })  }  const f = composeP([ doubleListPromise, toListPromise ])
  return f(1).then(res => {    expect(res).toEqual([ 1, 1 ])  })})