--- id: 5a24c314108439a4d403616b title: Use Default Props challengeType: 6 isRequired: false --- ## Description
React also has an option to set default props. You can assign default props to a component as a property on the component itself and React assigns the default prop if necessary. This allows you to specify what a prop value should be if no value is explicitly provided. For example, if you declare MyComponent.defaultProps = { location: 'San Francisco' }, you have defined a location prop that's set to the string San Francisco, unless you specify otherwise. React assigns default props if props are undefined, but if you pass null as the value for a prop, it will remain null.
## Instructions
The code editor shows a ShoppingCart component. Define default props on this component which specify a prop items with a value of 0.
## Tests
```yml tests: - text: The ShoppingCart component should render. testString: assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ShoppingCart)); return mockedComponent.find('ShoppingCart').length === 1; })(), 'The ShoppingCart component should render.'); - text: 'The ShoppingCart component should have a default prop of { items: 0 }.' testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ShoppingCart)); mockedComponent.setProps({items: undefined}); return mockedComponent.find(''ShoppingCart'').props().items === 0; })(), ''The ShoppingCart component should have a default prop of { items: 0 }.'');' ```
## Challenge Seed
```jsx const ShoppingCart = (props) => { return (

Shopping Cart Component

) }; // change code below this line ```
### After Test
```js ReactDOM.render(, document.getElementById('root')) ```
## Solution
```js const ShoppingCart = (props) => { return (

Shopping Cart Component

) }; // change code below this line ShoppingCart.defaultProps = { items: 0 } ```