用于渲染reactjs子组件的单元测试抛出错误

Question

我已经为组件“ CheckoutProducts”编写了单元测试，以验证其是否返回2个“ CheckoutProduct”子组件

组件层次结构为Checkout-> CheckoutProducts-> CheckoutProduct

代码如下：

       //////***** Checkout.js *****//////
        const products = [
                    { price: 199.99, pid: 'wf', qty:2},
                    { price: 9.99, pid: 'docgen', qty:3}
                ];
           this.setState({products:products})

         render () 
            {
              <CheckoutProducts checkoutProducts={this.state.products}/>
            }


        //////***** CheckoutProducts.js *****//////
            const checkoutProducts = (props) => {
            return (

                        Object.keys(props.checkoutProducts).map(productKey => (
                    <CheckoutProduct productName={props.checkoutProducts[productKey].pid} productQty={props.checkoutProducts[productKey].qty} />
                ))
            );
        }

        //////***** CheckoutProducts.test.js *****//////
        import { configure, shallow } from 'enzyme';
        import Adapter from 'enzyme-adapter-react-16';
        import CheckoutProducts from './CheckoutProducts';
        import CheckoutProduct from './CheckoutProduct/CheckoutProduct';

        configure({adapter: new Adapter()});

        describe('<CheckoutProducts />', () => {
         it('should render two <CheckoutProduct /> elements', () => {
           const checkoutProductsProps = [
                    { price: 199.99, pid: 'wf', qty:2},
                    { price: 9.99, pid: 'docgen', qty:3}
                ];
           let wrapper = shallow(<CheckoutProducts {...checkoutProductsProps} />);
           expect(wrapper.find(CheckoutProduct)).toHaveLength(2);
         });
        });

运行测试时出现以下错误

    TypeError: Cannot convert undefined or null to object
            at Function.keys (<anonymous>)

           5 |     return (
           6 |
        >  7 |                 Object.keys(props.checkoutProducts).map(productKey => (
             |                        ^
           8 |             <CheckoutProduct productName={props.checkoutProducts[productKey].pid} productQty={props.checkoutProducts[productKey].qty} />
           9 |         ))

任何帮助将不胜感激！