text: import sinon from 'sinon';
  import SimpleModel from 'model/simplemodel';
  
  describe('SimpleModel Mixin', function() {
  
      const model = new SimpleModel();
  
      it('returns undefined ', function() {
          expect(model.get('noExisting'), 'get with no attributes').to.be.undefined;
      });
  
      it('simplemodel', function() {
          expect(model.get('noExisting'), 'get with no attributes').to.be.undefined;
  
          model.set('attr', 'val');
          expect(model.get('attr'), 'set attribute with value').to.equal('val');
  
          const clone = model.clone();
          expect(clone.attr, 'clone gets the same attributes').to.equal('val');
  
          const spy = sinon.spy();
          model.change('attr', spy);
          expect(spy.callCount, 'change callback is invoked').to.equal(1);
          expect(spy.lastCall.args[1], 'change attribute with value').to.equal('val');
      });
  
      it('simplemodel', function() {
          expect(model.get('noExisting'), 'get with no attributes').to.be.undefined;
  
          model.set('attr', 'val');
          expect(model.get('attr'), 'set attribute with value').to.equal('val');
  
          const clone = model.clone();
          expect(clone.attr, 'clone gets the same attributes').to.equal('val');
  
          const spy = sinon.spy();
          model.change('attr', spy);
          expect(spy.callCount, 'change callback is invoked').to.equal(1);
          expect(spy.lastCall.args[1], 'change attribute with value').to.equal('val');
      });
  });
  