text: import test from 'blue-tape';
  import Darkener from '../../src/modules/darkener/Darkener';
  import ColorAdjust from '../../src/modules/coloradjust/ColorAdjust';
  
  test('Darkener =>', (expect) => {
    expect.test('::constructor', (expect) => {
      const darkener = new Darkener();
  
      expect.ok(
        darkener instanceof ColorAdjust,
        'Should use ColorAdjust as a base class',
      );
      expect.equal(
        darkener.shadingPercentage,
        -0.01,
        'Should shade down 1% of original color',
      );
      expect.end();
    });
  
    expect.end();
  });
  