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import { concat } from './concat.js'import { mergeWithFn } from './mergeWith.js'
test('happy', () => {  const result = mergeWithFn(    concat,    {      a      : true,      values : [ 10, 20 ],    },    {      b      : true,      values : [ 15, 35 ],    }  )  const expected = {    a      : true,    b      : true,    values : [ 10, 20, 15, 35 ],  }  expect(result).toEqual(expected)})
// https://github.com/ramda/ramda/pull/3222/files#diff-d925d9188b478d2f1d4b26012c6dddac374f9e9d7a336604d654b9a113bfc857describe('acts as if nil values are simply empty objects', () => {  it('if the first object is nil and the second empty', () => {    expect(mergeWithFn(      concat, undefined, {}    )).toEqual({})  })
  it('if the first object is empty and the second nil', () => {    expect(mergeWithFn(      concat, {}, null    )).toEqual({})  })
  it('if both objects are nil', () => {    expect(mergeWithFn(      concat, undefined, null    )).toEqual({})  })
  it('if the first object is not empty and the second is nil', () => {    expect(mergeWithFn(      concat, { a : 'a' }, null    )).toEqual({ a : 'a' })  })
  it('if the first object is nil and the second is not empty', () => {    expect(mergeWithFn(      concat, undefined, { a : 'a' }    )).toEqual({ a : 'a' })  })})