text: const expect = require('chai').expect;
  require('..')();
  
  describe('Array#prototype#Select', function() {
    /**
     * @param {number} a
     * @param {number} b
     */
    const add = (a, b) => a + b;
    const input = [1, 2, 3, 4, 5];
  
    it('Should sum each number when seed is supplied', function() {
      const expected = 15;
      const actual = input.Aggregate(0, add);
  
      expect(actual).to.eql(expected);
    });
  
    it('Should sum each number when seed is not supplied', function() {
      const expected = 15;
      const actual = input.Aggregate(add);
  
      expect(actual).to.eql(expected);
    });
  
    it('Should throw an error when accum is null', function() {
      expect(() => input.Aggregate(null)).to.throw();
    });
  
    it('Should throw an error when xform is undefined', function() {
      expect(() => input.Aggregate()).to.throw();
    });
  });
  