ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
85 lines
2.4 KiB
Markdown
85 lines
2.4 KiB
Markdown
---
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id: 5a24c314108439a4d4036168
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title: Write a React Component from Scratch
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challengeType: 6
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forumTopicId: 301424
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dashedName: write-a-react-component-from-scratch
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---
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# --description--
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Now that you've learned the basics of JSX and React components, it's time to write a component on your own. React components are the core building blocks of React applications so it's important to become very familiar with writing them. Remember, a typical React component is an ES6 `class` which extends `React.Component`. It has a render method that returns HTML (from JSX) or `null`. This is the basic form of a React component. Once you understand this well, you will be prepared to start building more complex React projects.
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# --instructions--
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Define a class `MyComponent` that extends `React.Component`. Its render method should return a `div` that contains an `h1` tag with the text: `My First React Component!` in it. Use this text exactly, the case and punctuation matter. Make sure to call the constructor for your component, too.
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Render this component to the DOM using `ReactDOM.render()`. There is a `div` with `id='challenge-node'` available for you to use.
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# --hints--
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There should be a React component called `MyComponent`.
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```js
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(getUserInput) =>
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assert(
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__helpers
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.removeWhiteSpace(getUserInput('index'))
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.includes('classMyComponentextendsReact.Component{')
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);
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```
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`MyComponent` should contain an `h1` tag with text `My First React Component!` Case and punctuation matter.
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```js
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assert(
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(function () {
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const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
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return mockedComponent.find('h1').text() === 'My First React Component!';
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})()
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);
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```
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`MyComponent` should render to the DOM.
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```js
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assert(document.getElementById('challenge-node').childNodes.length === 1);
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```
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`MyComponent` should have a constructor calling `super` with `props`.
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```js
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assert(
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MyComponent.toString().includes('MyComponent(props)') &&
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MyComponent.toString().includes('_super.call(this, props)')
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);
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```
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# --seed--
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## --seed-contents--
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```jsx
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// Change code below this line
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```
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# --solutions--
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```jsx
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// Change code below this line
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class MyComponent extends React.Component {
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constructor(props) {
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super(props);
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}
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render() {
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return (
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<div>
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<h1>My First React Component!</h1>
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</div>
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);
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}
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};
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ReactDOM.render(<MyComponent />, document.getElementById('challenge-node'));
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```
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