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

V4Fire core library

"use strict";

describe('core/prelude/function/memoize', () => {
  it('`once`', () => {
    const rand = Math.random.once(),
      res = rand();
    expect(Object.isNumber(res)).toBe(true);
    expect(rand()).toBe(res);
    expect(rand()).toBe(res);
  });
  it('`once` with arguments', () => {
    const fn = (i => i).once();
    expect(fn(1)).toBe(1);
    expect(fn(2)).toBe(1);
  });
  it('`Function.once`', () => {
    const rand = Function.once(Math.random),
      res = rand();
    expect(Object.isNumber(res)).toBe(true);
    expect(rand()).toBe(res);
    expect(rand()).toBe(res);
  });
});