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import { apply } from './apply.js'import { converge } from './converge.js'import { identity } from './identity.js'import { prop } from './prop.js'import { sum } from './sum.js'import { unapply } from './unapply.js'
test('happy', () => {  const fn = unapply(identity)  expect(fn(    1, 2, 3  )).toEqual([ 1, 2, 3 ])  expect(fn()).toEqual([])})
test('returns a function which is always passed one argument', () => {  const fn = unapply(function (){    return arguments.length  })  expect(fn('x')).toBe(1)  expect(fn('x', 'y')).toBe(1)  expect(fn(    'x', 'y', 'z'  )).toBe(1)})
test('forwards arguments to decorated function as an array', () => {  const fn = unapply(xs => '[' + xs + ']')  expect(fn(2)).toBe('[2]')  expect(fn(2, 4)).toBe('[2,4]')  expect(fn(    2, 4, 6  )).toBe('[2,4,6]')})
test('returns a function with length 0', () => {  const fn = unapply(identity)  expect(fn).toHaveLength(0)})
test('is the inverse of R.apply', () => {  let a, b, c, d, e, f, g, n  const rand = function (){    return Math.floor(200 * Math.random()) - 100  }
  f = Math.max  g = unapply(apply(f))  n = 1  while (n <= 100){    a = rand()    b = rand()    c = rand()    d = rand()    e = rand()    expect(f(      a, b, c, d, e    )).toEqual(g(      a, b, c, d, e    ))    n += 1  }
  f = function (xs){    return '[' + xs + ']'  }  g = apply(unapply(f))  n = 1  while (n <= 100){    a = rand()    b = rand()    c = rand()    d = rand()    e = rand()    expect(f([ a, b, c, d, e ])).toEqual(g([ a, b, c, d, e ]))    n += 1  }})
test('it works with converge', () => {  const fn = unapply(sum)  const convergeFn = converge(fn, [ prop('a'), prop('b'), prop('c') ])  const obj = {    a : 1337,    b : 42,    c : 1,  }  const expected = 1337 + 42 + 1  expect(convergeFn(obj)).toEqual(expected)})