The last challenge demonstrated how to pass information from a parent component to a child component as <code>props</code> or properties. This challenge looks at how arrays can be passed as <code>props</code>. To pass an array to a JSX element, it must be treated as JavaScript and wrapped in curly braces.
The child component then has access to the array property <code>colors</code>. Array methods such as <code>join()</code> can be used when accessing the property.
This will join all <code>colors</code> array items into a comma separated string and produce:
<code><p>green, blue, red</p></code>
Later, we will learn about other common methods to render arrays of data in React.
</section>
## Instructions
<sectionid='instructions'>
There are <code>List</code> and <code>ToDo</code> components in the code editor. When rendering each <code>List</code> from the <code>ToDo</code> component, pass in a <code>tasks</code> property assigned to an array of to-do tasks, for example <code>["walk dog", "workout"]</code>. Then access this <code>tasks</code> array in the <code>List</code> component, showing its value within the <code>p</code> element. Use <code>join(", ")</code> to display the <code>props.tasks</code>array in the <code>p</code> element as a comma separated list. Today's list should have at least 2 tasks and tomorrow's should have at least 3 tasks.
</section>
## Tests
<sectionid='tests'>
```yml
tests:
- text: The <code>ToDo</code> component should return a single outer <code>div</code>.
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return mockedComponent.children().first().childAt(2).name() === "List"; })(), "The third child of the <code>ToDo</code> component should be an instance of the <code>List</code> component.");'
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return mockedComponent.children().first().childAt(4).name() === "List"; })(), "The fifth child of the <code>ToDo</code> component should be an instance of the <code>List</code> component.");'
- text: Both instances of the <code>List</code> component should have a property called <code>tasks</code> and <code>tasks</code> should be of type array.
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return Array.isArray(mockedComponent.find("List").get(0).props.tasks) && Array.isArray(mockedComponent.find("List").get(1).props.tasks); })(), "Both instances of the <code>List</code> component should have a property called <code>tasks</code> and <code>tasks</code> should be of type array.");'
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return mockedComponent.find("List").get(0).props.tasks.length >= 2; })(), "The first <code>List</code> component representing the tasks for today should have 2 or more items.");'
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return mockedComponent.find("List").get(1).props.tasks.length >= 3; })(), "The second <code>List</code> component representing the tasks for tomorrow should have 3 or more items.");'
- text: The <code>List</code> component should render the value from the <code>tasks</code> prop in the <code>p</code> tag as a comma separated list, for example <code>walk dog, workout</code>.
testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(ToDo)); return mockedComponent.find("p").get(0).props.children === mockedComponent.find("List").get(0).props.tasks.join(", ") && mockedComponent.find("p").get(1).props.children === mockedComponent.find("List").get(1).props.tasks.join(", "); })(), "The <code>List</code> component should render the value from the <code>tasks</code> prop in the <code>p</code> tag as a comma separated list, for example <code>walk dog, workout</code>.");'