moy-fp/test/List/nthList.test.js

A functional programming library.

import __ from '../../src/Function/__'
/**
 * Number -> [a] -> a | undefined
 */
import nthList from '../../src/List/nthList'

test('nthList(not using __), positive number', () => {
  expect(
    nthList(1)([1, 2, 3, 4])
  ).toBe(2)
})

test('nthList(not using __), negative number', () => {
  expect(
    nthList(-2)([1, 2, 3, 4])
  ).toBe(3)
})

test('nthList(using __), positive number', () => {
  expect(
    nthList(__, [1, 2, 3, 4])(1)
  ).toBe(2)
})