prottle.test.js

require('chai')
  .use(require('chai-as-promised'))
  .should();

describe('prottle.js', () => {
  let prottle;

  beforeEach(() => {
    prottle = require('./prottle.js');
  });

  it('rejects with limit error', () => {
    return prottle()
      .catch((err) => {
        err.message.should.equal('Limit must be at least 1');
      });
  });

  it('rejects with limit error', () => {
    return prottle(0)
      .catch((err) => {
        err.message.should.equal('Limit must be at least 1');
      });
  });

  it('rejects with limit error', () => {
    return prottle('dsad')
      .catch((err) => {
        err.message.should.equal('Limit must be at least 1');
      });
  });

  it('rejects with array error', () => {
    return prottle(1, 'boo')
      .catch((err) => {
        err.message.should.equal('Array of promises required');
      });
  });

  it('does not modify given array', () => {
    const arr = [
      () => Promise.resolve(1),
      () => Promise.resolve(2),
      () => Promise.resolve(3)
    ];

    let length = arr.length;

    return prottle(1, arr)
      .then(() => {
        arr.length.should.equal(length);
      });
});

  it('resolves', () => {
    return prottle(3, [
      () => Promise.resolve(1),
      () => Promise.resolve(2),
      () => Promise.resolve(3),
      () => Promise.resolve(4),
      () => Promise.resolve(5)
    ])
      .should.eventually.eql([
        1, 2, 3, 4, 5
      ]);
  });

  it('rejects', () => {
    return prottle(2, [
      () => Promise.resolve(1),
      () => Promise.resolve(2),
      () => Promise.resolve(3),
      () => Promise.reject('beep boop'),
      () => Promise.resolve(5)
    ])
      .should.be.rejectedWith('beep boop');
  });
});