@v4fire/core/lib/core/prelude/function/compose/spec.js

V4Fire core library

"use strict";

describe('core/prelude/function/compose', () => {
  it('`compose`', () => {
    const a = v => v - 2,
      b = v => v * 4;
    expect(a.compose(b)(2)).toBe(0);
  });
  it('`compose` with promises', async () => {
    const a = v => Promise.resolve(v - 2),
      b = v => Promise.resolve(v * 4);
    expect(await a.compose(b)(2)).toBe(0);
  });
  it('`Function.compose`', () => {
    const a = v => v - 2,
      b = v => v * 4;
    expect(Function.compose(a, b)(2)).toBe(6);
  });
  it('`Function.compose` with promises', async () => {
    const a = v => Promise.resolve(v - 2),
      b = v => Promise.resolve(v * 4);
    expect(await Function.compose(a, b)(2)).toBe(6);
  });
});