How to mock data with props in your React Functional Component

How to mock data with props in your React Functional Component

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In my React application, i am developing a screen using Functional Component. I want to populate the data on the screen with mock data until my API is ready. I basically have an Accordion with open state where i want to display the names. Right now, i am hardcoding name to populate that. Later, i will be replacing with the actual data coming from Store. So to do that i am defining the hard coded data like below in my component itself as after the API is ready, my props will have all the required data.

function MyComponent (props) {
    props={
        history: {},
        data:[
          {
            name:’XYZ’,
          },
          {
            name:’ABC’,
          }
        ]
    }

    return (
       <div>Content goes here </div>
     )
}

This throws me error. I want to understand if i am doing this correctly as i need to read the data values inside my div.


Props are immutable, so you should not change them. Instead, you could mock the props that you are passing to MyComponent


Example: In the parent component:

function MyApp() {
  const mockProps={
    history: {},
    data:[
      name:’XYZ’,
    ]
  }

  return <MyComponent {...mockProps}/>
}

and in MyComponent

function MyComponent (props) {
 // do something with props here
 return <div>Content goes here </div>
}

This week I learned: How to mock a Render Props Component in , Understanding the Render Props component pattern in React (a.k.a. the The gist is that you pass a rendering function to a data management� If we take a quick look at React’s docs again, we find an interesting, but easy-to-miss, bit of information: […] useRef will give you the same ref object on every render. It doesn’t matter what we do. Throughout the lifetime of your component, React will give us the exact same ref object in memory.


It is probably best to mock this data as coming from parent container, that way when you add Redux library later, you can simply change /where/ props are being sent from.

e.g

in Parent JS:

const Parent = props => {
const [accordionData, setData] = useState(['#1', '#2', '#3'])

/ ... rest of component / 

return <Accordion accordionData={accordionData} />

}  

in

const Accordion = props => {

    const { accordionData } = props // pull props from parent component.

    const mapAccordionData = accordionData.map(el => { return <div key={el}>el</div> })

    return mapAccordionData

}

Something like this should work.

ParentJS is feeding the accordion an array of data via parent->child props. Later this will be store->child props. Accordion (child) is then rendering that data to so the user can see it via divs.

Testing state changes in React functional components, Learn how to test your React functional components and the state changes for but you don't want that data to be available for the entire application. styles. scss"; export default class App extends Component { constructor(props) This function creates a mock function similar to jest.fn while tracking the� In React's unidirectional flow of data, props are the easiest mode to pass data, state and methods from a parent component to a child, and they are read-only. In the example below, the parent component <Deer/> passes a props (an object) consisting of the JSX attribute called skinColour with the value brown to its child component <Fawn/> .


You would pass props into a component. They should come from either a parent's component state or a store (like Redux store).

function MyComponent(props) {
  return <div>{props.hello}</div>;
}


class ParentComponent extends React.Component {
  state = {
    hello: 'Hello World!',
  }

  render() {
    return <MyComponent hello={this.state.hello} />;
  }
}

You can also pass a function that changes the state of the parent making the props also change for MyComponent. It won't mutate them but rather return a new state and therefore pass a new set of props. Let me know if you need any further explanation.

Testing Recipes – React, Mocking out these modules with dummy replacements can make it easier to write tests for your own code. Consider a Contact component that embeds a third-party function Map(props) { return ( <LoadScript id="script-loader" + props.email}> email </a> or on their <a data-testid="site"� React Function Component: props. Let's learn about a React Function Component with props. In React, props are used to pass information from component to component. If you don't know about props in React, cross-read the linked article. Essentially props in React are always passed down the component tree:


Thinking in React – React, Imagine that we already have a JSON API and a mock from our designer. Use the same techniques for deciding if you should create a new function or object. Component { render() { const product = this.props.product; const name� Props is short for properties. You give properties to components. Just like your parents gave you your eye color your components in React give properties to their children.


Test Renderer – React, import TestRenderer from 'react-test-renderer'; function Link(props) { return <a It doesn't use the real DOM, but it still fully renders the component tree into function to TestRenderer.create as the option, which allows for custom mock refs. ConceptsAdvanced GuidesAPI ReferenceHooksTestingConcurrent Mode� Suspense is a relatively new React feature that lets your component display something as a fallback while it waits for some long-running operation to finish. Obviously, data fetching is a long-running operation, and you may want to display something like a message, progress bar, or spinner while your data is being fetched.


Testing React Components with react-test-renderer, and the Act API, unit testing React components; functional testing for React We bypassed completely the onClick props of our button: But it's not that bad because we're interested in mocking the API with a fake JSON response. First we� ReactJS does not allow a component to modify its own props as a rule. The only way to modify the props is to change the props being passed to the child component. This is generally done by passing a reference of a function in the parent component to the child component. Props have more significance in functional components for the simple reason that functional components do not have access to a state, unlike class-based components.