moy-fp/test/Object/merge.test.js

A functional programming library.

import __ from '../../src/Function/__'
/**
 * {k: v} -> {k: v} -> {k: v}
 */
import merge from '../../src/Object/merge'

test('merge(not using __), has no the same key', () => {
  expect(
    merge({a: 1, b: 2})({c: 3})
  ).toEqual({a: 1, b: 2, c: 3})
})

test('merge(not using __), has the same key', () => {
  expect(
    merge({a: 1, b: 2})({a: 4, c: 3})
  ).toEqual({a: 4, b: 2, c: 3})
})

test('merge(using __), has no the same key', () => {
  expect(
    merge(__, {c: 3})({a: 1, b: 2})
  ).toEqual({a: 1, b: 2, c: 3})
})