'use strict';

import {isArray, isUndefined} from 'util';
import * as chai from 'chai';

const expect = chai.expect;

export function getInstance(cls, args?) {
  if(!isUndefined(args)) {
    args = isArray(args) ? args : [args];
  } else {
    args = [];
  }
  return new cls(...args);
}

export function checkClassExport(cls, args?) {
  it('export class', () => {
    expect(cls).to.be.an('function');
  });
    
  it('create instance', () => {
    expect(getInstance(cls, args)).to.be.instanceof(cls);
  });
}

export function checkAttributes(cls, options) {
  describe('attributes', () => {
    Object.keys(options).forEach(type => {
      describe(type, () => {
        const instance = getInstance(cls, options[type].args);
        Object.keys(options[type].expected).forEach(attr => {
          it(attr, () => {
            expect(instance[attr]).to.be.equal(options[type].expected[attr]);
          });
        })
      });
    });
  });
}