moy-fp/test/Functor/fork.test.js

A functional programming library.

import __ from '../../src/Function/__'
/**
 * Task T => (a -> c) -> (a -> b) -> T a -> ()
 */
import fork from '../../src/Functor/fork'
import Task from '../../src/Functor/Task/index'

// in fact, the test is not valid since Task is asynchronous
test('fork(not using __)', () => {
  expect(
    fork(x => x - 1)(x => x + 1)(Task.of(12))
  ).toBe(13)
})

test('fork(using __)', () => {
  expect(
    fork(x => x - 1, __, Task.of(12))(x => x + 1)
  ).toBe(13)
})