describe('Histogram', function() {
  beforeEach(() => spyOn($, 'plot'));

  describe('constructor', () =>
    it('instantiate the data arrays', function() {
      const histogram = new Histogram(1, []);
      expect(histogram.xTicks).toEqual([]);
      expect(histogram.yTicks).toEqual([]);
      expect(histogram.data).toEqual([]);
  })
);

  describe('calculate', function() {
    beforeEach(function() {
      this.histogram = new Histogram(1, [[null, 1], [1, 1], [2, 2], [3, 3]]);
    });

    it('store the correct value for data', function() {
      expect(this.histogram.data).toEqual([[1, Math.log(2)], [2, Math.log(3)], [3, Math.log(4)]]);
  });

    it('store the correct value for x ticks', function() {
      expect(this.histogram.xTicks).toEqual([[1, '1'], [2, '2'], [3, '3']]);
  });

    it('store the correct value for y ticks', function() {
      expect(this.histogram.yTicks).toEqual;
    });
  });

  describe('render', () =>
    it('call flot with correct option', function() {
      new Histogram(1, [[1, 1], [2, 2], [3, 3]]);

      const firstArg = $.plot.calls.mostRecent().args[0];
      const secondArg = $.plot.calls.mostRecent().args[1];
      const thirdArg = $.plot.calls.mostRecent().args[2];

      expect(firstArg.selector).toEqual($("#histogram_1").selector);
      expect(secondArg).toEqual([{
        data: [[1, Math.log(2)], [2, Math.log(3)], [3, Math.log(4)]],
        bars: {
          show: true,
          align: 'center',
          lineWidth: 0,
          fill: 1.0
        },
        color: "#b72121"
      }
      ]);
      expect(thirdArg).toEqual({
        xaxis: {
          min: -1,
          max: 4,
          ticks: [[1, '1'], [2, '2'], [3, '3']],
          tickLength: 0
        },
        yaxis: {
          min: 0.0,
          max: Math.log(4) * 1.1,
          ticks: [[Math.log(2), '1'], [Math.log(3), '2'], [Math.log(4), '3']],
          labelWidth: 50
        }
      });
    })
  );
});