React State Storing & Outputting Duplicate Values - javascript

Slight issue here which I think is relatively simple to solve but I can't quite get my head around. I'm quite new to React. I've decided to make a small sample app which just takes the input from two fields, saves them to Firebase and outputs those values on the page. It works completely fine in terms of submitting data and retrieving it, but when I click the submit button to add the data to Firebase it seems to duplicate the data stored in the state and render them twice:
Parent Component:
import React, { Component, Fragment } from 'react';
import firebase from '../../config/firebase';
import QuestFormField from './QuestFormField/QuestFormField';
import QuestFormSelection from './QuestFormSelection/QuestFormSelection';
import classes from './QuestForm.css';
class QuestForm extends Component {
state = {
value: '',
points: 0,
items: []
}
questHandler = e => {
this.setState({
value: e.target.value,
});
}
pointsHandler = e => {
this.setState({
points: e.target.value,
});
}
submitHandler = e => {
e.preventDefault();
const itemsRef = firebase.database().ref('quest');
const items = {
quest: this.state.value,
points: this.state.points
}
itemsRef.push(items);
this.setState({
value: '',
points: 0
});
}
render () {
return (
<Fragment>
<form className={classes.Form} onSubmit={this.submitHandler}>
<QuestFormField val='Quest' inputType='text' name='quest' value={this.state.value} changed={this.questHandler} />
<QuestFormField val='Points' inputType='number' name='points' value={this.state.points} changed={this.pointsHandler} />
<button>Away! To Firebase!</button>
</form>
<QuestFormSelection />
</Fragment>
);
}
}
export default QuestForm;
Child Component (Form Fields)
import React from 'react';
import classes from './QuestFormField.css';
const QuestFormField = (props) => (
<div className={classes.Container}>
<label htmlFor={props.name}>{props.val}</label>
<input type={props.inputType} name={props.name} onChange={props.changed}/>
</div>
);
export default QuestFormField;
Child Component B (Data Retriever/Displayer)
import React, { Component, Fragment } from 'react';
import firebase from '../../../config/firebase';
import classes from './QuestFormSelection.css';
class QuestFormSelection extends Component {
state = {
quests: []
}
componentDidMount() {
const database = firebase.database();
const quests = [];
database.ref('quest').on('value', (snapshot) => {
snapshot.forEach((childSnapshot) => {
quests.push({
id: childSnapshot.key,
quest: childSnapshot.val().quest,
points: childSnapshot.val().points,
});
});
console.log(quests);
this.setState(() => {
return {
quests: quests
}
});
console.log(this.state.quests);
});
}
render () {
return (
<section className='display-item'>
<div className="wrapper">
{this.state.quests.map(quest => (
<div key={quest.key}>
<p>{quest.quest}</p>
<p>{quest.points}</p>
</div>
))}
</div>
</section>
)
}
}
export default QuestFormSelection;
Example of behaviour here:
https://i.gyazo.com/c70972f8b260838b1673d360d1bec9cc.mp4
Any pointers would help :)

I haven't used firebase myself, but it looks like the code below is setting up a listener to "quest" changes which will execute each time a change occurs, but you defined const quests = [] outside of the db change handler. This means that on the second change, you will push everything in the snapshot to the same quests array that may have already had previous snapshots added to it. I believe you can fix this by moving the quests variable inside the listener function as shown below.
componentDidMount() {
const database = firebase.database();
database.ref('quest').on('value', (snapshot) => {
const quests = [];
snapshot.forEach((childSnapshot) => {
quests.push({
id: childSnapshot.key,
quest: childSnapshot.val().quest,
points: childSnapshot.val().points,
});
});
console.log(quests);
this.setState(() => {
return {
quests: quests
}
});
console.log(this.state.quests);
});
}

Related

JS/React - Live Search Bar With Mapping

After two days of being stuck on this component, I'm asking for any sort of help. I'm trying to search an API based on user input, and then filter that down to a more specific option as the user keeps typing. After solving a dozen or so errors, I'm still left with "Can't find variable 'Query'", and I just can't seem to find or figure out what exactly it's wanting. There was another post on here that led me in the right direction, but didn't provide any sort of answer for the issue I'm having. Any help here would be appreciated.
import axios from "axios";
import axiosRateLimit from "axios-rate-limit";
import React, { Component } from "react";
import SearchBar from "react-native-elements/dist/searchbar/SearchBar-ios";
class CardSearch extends Component {
state = {
data: [],
filteredData: [],
query: "",
};
handleInputChange = (event) => {
const query = event.target.value;
this.setState((prevState) => {
const filteredData = prevState.data.filter((element) => {
return element.name.toLowerCase().includes(query.toLowerCase());
});
return {
query,
filteredData,
};
});
};
getData = () => {
axiosRateLimit(
axios.get(`https://api.scryfall.com/cards/autocomplete?q=${query}`),
{ maxRPS: 8 }
)
.then((response) => response.json())
.then((data) => {
const { query } = this.state;
const filteredData = data.filter((element) => {
return element.name.toLowerCase().includes(query.toLowerCase());
});
this.setState({
data,
filteredData,
});
});
};
componentWillMount() {
this.getData();
}
render() {
return (
<>
<SearchBar
placeholder='Search For...'
value={this.state.query}
onChange={this.handleInputChange}
/>
<div>
{this.state.filteredData.map((i) => (
<p>{i.name}</p>
))}
</div>
</>
);
}
}
export default CardSearch;
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
Have a look at this Link. You are not setting the State in a Constructor. And as already mentioned in the comments you will then have to access the query using this.state.query
https://reactjs.org/docs/state-and-lifecycle.html#adding-local-state-to-a-class
The Code-Sample from the React Documentation:
class Clock extends React.Component {
constructor(props) {
super(props);
this.state = {date: new Date()};
}
render() {
return (
<div>
<h1>Hello, world!</h1>
<h2>It is {this.state.date.toLocaleTimeString()}.</h2>
</div>
);
}
}

Sending API data in Gatsby to be used in Chart.js

I am trying to send API data being called from my index.js to my ChartData.js. index.js is a page and ChartData.js is a component in Gatsby, so to begin with I could not figure out if Gatsby's Link to="" function only work from one page to another or if it can send data from a page to a component.
The issue is when I try to access the sent data from index.js to ChartData.js in the line {props.location.state.companyName} I am getting the error: TypeError: props.location is undefined
I plan to switch out labels: ['x', 'y'] for something like labels: [{props.location.state.companyName}, {props.location.state.symbol} etc. I am not sure if this would be the correct syntax either.
A more detailed explanation here: https://www.youtube.com/watch?v=No9cqzqlKS0&feature=youtu.be
index.js:
import React from "react"
import { Link } from "gatsby"
import axios from "axios"
import "../css/style.css"
import Layout from "../components/layout"
import { symbol } from "prop-types"
import ChartData from "../components/ChartData"
export default class index extends React.Component {
state = {
companyName: "",
previousClose: "",
marketCap: "",
change: "",
symbol: "",
topStocks: [],
Yearweekhigh: "",
Yearweeklow: "",
avgTotalVolume: "",
peRatio: ""
}
componentDidMount() {
const API_KEY = '*******************';
axios.get(`https://cloud.iexapis.com/stable/stock/market/previous?token=${API_KEY}`)
.then(res => {
console.log(res)
const topStocks = res.slice(1);
this.setState({ topStocks })
})
}
clickHandler = (event) => {
if (event.keyCode === 13) {
const query = event.target.value;
const API_KEY = '*******************';
axios.get(`https://cloud.iexapis.com/stable/stock/${query}/quote?token=${API_KEY}`)
.then(res => {
const companyName = res.data['companyName'];
this.setState({ companyName })
const previousClose = res.data['previousClose'];
this.setState({ previousClose })
const marketCap = res.data['marketCap'];
this.setState({ marketCap })
const change = res.data['change'];
this.setState({ change })
const symbol = res.data['symbol'];
this.setState({ symbol })
const Yearweekhigh = res.data['week52High'];
this.setState({ Yearweekhigh })
const Yearweeklow = res.data['week52Low'];
this.setState({ Yearweeklow })
const avgTotalVolume = res.data['avgTotalVolume'];
this.setState({ avgTotalVolume })
const peRatio = res.data['peRatio'];
this.setState({ peRatio })
})
}
}
render() {
return (
<Layout>
<div class = "main-div">
<input type="search" class="main-search" onKeyDown={event => this.clickHandler(event)}/>
<table>
<tr>
<th>Ticker-Symbol</th>
<th>Market Cap</th>
<th>Previous Close</th>
</tr>
<tr>
<td>
<Link to='/details/' state={{
setState: this.state.symbol,
companyName: this.state.companyName,
previousClose: this.state.previousClose,
marketCap: this.state.marketCap,
change: this.state.change,
Yearweekhigh: this.state.Yearweekhigh,
Yearweeklow: this.state.Yearweeklow,
avgTotalVolume: this.state.avgTotalVolume,
peRatio: this.state.peRatio
}}>
{this.state.symbol}</Link>
<Link to='/ChartData/' state={{
setState: this.state.symbol,
companyName: this.state.companyName,
previousClose: this.state.previousClose,
marketCap: this.state.marketCap,
change: this.state.change,
Yearweekhigh: this.state.Yearweekhigh,
Yearweeklow: this.state.Yearweeklow,
avgTotalVolume: this.state.avgTotalVolume,
peRatio: this.state.peRatio
}}></Link>
</td>
<td>{this.state.marketCap}</td>
<td>{this.state.previousClose}</td>
</tr>
</table>
</div>
<div>
{
this.state.topStocks.length && this.state.topStocks.map(stock => (
<h1>{stock.symbol}</h1>
))
}
</div>
<ChartData />
</Layout>
)
}
}
details.js
//import { Link } from "gatsby"
import axios from 'axios';
import React, { useEffect, useState } from 'react';
import Layout from '../components/layout';
import "../css/style.css"
const Details = props => {
const [yourState, setYourState] = useState('');
useEffect(() => {
}, []);
return <Layout>
<div>
<h1 class="details-company-name">{props.location.state.companyName}</h1>
<div class = "details-div">
<div class="details-div-1">
<p>Open {} </p>
<p>High {} </p>
<p>Low {} </p>
<p>52 WK HIGH <h2>{props.location.state.Yearweekhigh}</h2> </p>
<p>52 WK LOW <h2>{props.location.state.Yearweeklow}</h2> </p>
</div>
<div class="details-div-2">
<p>VOLUME</p>
<p>AVG VOL <h2>{props.location.state.avgTotalVolume}</h2> </p>
<p>MKT CAP <h2>{props.location.state.marketCap}</h2></p>
<p>P/E RATIO <h2>{props.location.state.peRatio}</h2></p>
<p>DIV/YIELD</p>
</div>
</div>
</div>
</Layout>;
};
export default Details;
ChartData.js
import React, {useState, useEffect } from "react";
import { Line } from "react-chartjs-2";
const ChartData = props => {
const [yourState, setYourState] = useState('');
const chart = () => {
setYourState({
labels: ['x', 'y'],
datasets: [
{
level: 'level of xyz',
data: [22, 55]
}
]
})
}
useEffect(() => {
chart()
}, [])
return(
<div>
<h1>Hello</h1>
{props.location.state.companyName}
<div>
<Line data={yourState}/>
</div>
</div>
)
}
export default ChartData;
There's a quite a bit going on here that needs clarification. You mention graphql in the title, but there's no graphql in your code.
You are using axios to fetch data at runtime in the componentDidMount lifecycle method, and then setting the result to state.
I assume that once you have that data, all you want to do is pass it to your chart component so that it can render itself on the index page.
Consider the following example which does the same thing; Fetches some data from the Rick & Morty api, sets the results to state, and passes the relevant part of that state via props directly to the <Characters /> component.
From there, the <Characters /> component has everything it needs in order to render. (It has no state, and is not concerned about where the data actually came from).
// index.js
import React from 'react';
import './App.css';
import Characters from './Characters'
const api = "https://rickandmortyapi.com/api/character/";
class IndexPage extends React.Component {
constructor(props) {
super(props);
this.state = {
error: null,
isLoaded: false,
items: []
};
}
componentDidMount() {
fetch(api)
.then(res => res.json())
.then(
json => {
console.log(json)
this.setState({
isLoaded: true,
data: json.results
});
},
// Note: it's important to handle errors here
// instead of a catch() block so that we don't swallow
// exceptions from actual bugs in components.
error => {
this.setState({
isLoaded: true,
error
});
}
);
}
render() {
const { error, isLoaded, data } = this.state;
if (error) {
return <div>Error: {error.message}</div>;
} else if (!isLoaded) {
return <div>Loading...</div>;
} else {
return (
<Characters data={data} />
);
}
}
}
export default IndexPage;
// Characters.js
import React from 'react';
class Characters extends React.Component {
render() {
return (
<ul>
{this.props.data.map(item => (
<li key={item.id}>
<dl>
<dt>Name:</dt>
<dd>{item.name}</dd>
<dt>Species:</dt>
<dd>{item.species}</dd>
<dt>Status:</dt>
<dd>{item.status}</dd>
</dl>
</li>
))}
</ul>
);
}
}
export default Characters;
Codesandbox Example using functional components and hooks
Gatsby’s <Link> component allows you to link between pages (and does some other stuff like prefetching resources, and can share data between pages). As you are rendering the <ChartData /> component on the index page, this is not required to solve your problem.
Using <Link> with state works because details is a gatsby page. As <ChartData> is not a page, you can't *link* to it.

"Cannot read property 'map' of undefined" within React, what's wrong here?

Trying to get my head around props so forgive me if its a silly mistake. I am trying to pass all of my data into one variable and pass that out into props (using {item.text} and {item.key}), however, my ".map" isn't picking up anything and there's a bunch of errors, what's wrong with my code?
The problem lays specifically here in this block of code
createList(list) {
return <li>{list.text}</li>
}
render() {
var entries = this.state.list
var finalEntries = entries.props.map(this.createList)
Here is the code in full
import React from "react";
import "./App.css";
import { isTemplateElement } from "#babel/types";
class TodoListt extends React.Component {
state = {};
constructor(props) {
super(props);
this.state = {
userInput: "",
list: [],
};
}
changeUserInput(input) {
this.setState({
userInput: input
})
}
addToList(input) {
let listArray = this.state.list;
listArray.push(input);
var newItem = {
text: listArray,
key: Date.now()
};
this.setState(prevState => {
return {
list: prevState.list.concat(newItem)
};
});
this.setState({
list: listArray
})
}
createList(list) {
return <li>{list.text}</li>
}
render() {
var entries = this.state.list
var finalEntries = entries.props.map(this.createList)
return (
<div className="to-do-list-main">
<input
onChange={(e) => this.changeUserInput(e.target.value)}
value={this.state.userInput}
type="text"
/>
<button onClick={() => this.addToList(this.state.userInput)}>Press me</button>
<ul>
{this.testingSetup()}
</ul>
</div>
);
}
}
export default TodoListt;
You can use the spread operator to add to an existing array. Simply add a new object to the array in the state, and then clear the user input, ready for another item. Based on your code, here's a simple example of adding to a state list (haven't run myself, so just check for syntax errors and such):
import React from "react";
import "./App.css";
import { isTemplateElement } from "#babel/types";
class TodoList extends React.Component {
state = {};
constructor(props) {
super(props);
this.state = {
userInput: "",
list: [],
};
}
changeUserInput(input) {
this.setState({
userInput: input
})
}
addToList() {
const { list, userInput } = this.state;
// Add item to state list using spread operator and clear input
this.setState({
list: [...list, {text:userInput, key: Date.now()}],
userInput: ""
});
}
render() {
return (
<div className="to-do-list-main">
<input
onChange={(e) => this.changeUserInput(e.target.value)}
value={this.state.userInput}
type="text"
/>
<button onClick={() => this.addToList()}>Press me</button>
<hr/>
{/* For each item in the list, render the contents */}
{this.state.list.map(item => (
<div key={item.key}>
<h3>{item.text}</h3>
<p>Time: {item.key}</p>
</div>
))}
</div>
);
}
}
export default TodoList;

React.js moving on to the next list

I'm making a movie search page. When I search something, it goes through the data base and find the very first match and display on the page. However, I want to create a function, so when I click next, page displays next movie in the data base. My code follows:
import React, { Component, PropTypes } from 'react';
import SearchBar from './Bar/index.js';
import SearchResult from './Result/index.js';
import axios from 'axios';
import './index.css';
class SearchArea extends Component {
constructor(props) {
super(props);
this.state = {
searchText: '',
searchResult: {},
result: false,
count: 0
};
}
handleSearchBarChange(event) {
this.setState({searchText: event.target.value});
}
handleSearchBarSubmit(event) {
event.preventDefault();
const movie = this.state.searchText;
axios.get(`https://api.themoviedb.org/3/search/movie?api_key=c6cd73ec4677bc1d7b6560505cf4f453&language=en-US&query=${movie}&page=1&include_adult=false`)
.then(response => {
if(response.data.results.length >= 0) {
const i = 0;
const {
title,
overview,
release_date: releaseDate
} = response.data.results[this.state.count];
const posterPath = 'https://image.tmdb.org/t/p/w154' + response.data.results[this.state.count].poster_path;
this.setState({
searchResult: {
title,
posterPath,
overview,
releaseDate
},
result: true
});
}
else {
this.setState({
searchResult: {
title: 'No Result',
overview: 'No Overview Available',
posterPath: ''
},
result: true
});
}
})
}
handleSearchNext(event) {
this.handelSearchBarSubmit.overview = response.data.results[1];
}
handleResultClose() {
this.setState({
searchResult: {},
result: false
});
}
render() {
return (
<div>
<SearchBar
value = {this.state.searchText}
onChange = {this.handleSearchBarChange.bind(this)}
onSubmit = {this.handleSearchBarSubmit.bind(this)}
onNext = {this.handleSearchNext.bind(this)}
/>
{this.state.result &&
<SearchResult
searchResult = {this.state.searchResult}
onClose = {this.handleResultClose.bind(this)}
onAdd = {this.props.onAdd}
/>
}
</div>
);
}
}
SearchArea.propTypes = {
onAdd: PropTypes.func.isRequired
};
export default SearchArea;
I can't seem to figure out how to make handleSearchNext. Please help
EDIT
Following is the SearchBar code
import React, { PropTypes } from 'react';
import { Button } from 'semantic-ui-react';
import styles from './index.css';
const SearchBar = (props) => {
return (
<div>
<form onSubmit={(event) => props.onSubmit(event)}>
<input
className="searchBar"
type="text"
placeholder="Search Here"
value={props.value}this
onChange={(event) => props.onChange(event)}
onNext={(event) => props.onChange(event)}
onBack={(event) => props.onChange(event)}
/>
<Button className="button" type="submit">Sumbit</Button>
</form>
<Button className={styles.button} type="previous">Back</Button>
<Button className="button" type="next">Next</Button>
</div>
);
};
SearchBar.propTypes = {
value: PropTypes.string.isRequired,
onChange: PropTypes.func.isRequired,
onSubmit: PropTypes.func.isRequired,
onBack: PropTypes.func.isRequired,
onNext: PropTypes.func.isRequired
};
export default SearchBar;
You could have your server respond with not only the requested title, but also the next one. That way, when you click on Next, you can immediately display the next movie without waiting for a response, while still querying it in the background by name or id (so that you have the next after it, etc.).
Edit: If I misunderstood what you meant and you already have this (it looks like you are actually querying a whole page of movies at once), you probably simply want something like
handleSearchNext(event) {
this.setState({ searchResult: response.data.results[1], result: true });
}
and handle specially the case when you hit the last item on the page.

unit testing a react component with mocha

I'm working through a TodoMVC example for the Redux ecosystem. I've completed working code for the example and am now working through the creation of tests for each of the elements of the application.
For actions and reducers, the testing is very straightforward, but for the components, writing tests has proven somewhat more challenging.
My general component architecture looks like this:
Home.js
\-App.js
\-TodoList.js
\-TodoItem.js
\-TodoInput.js
Writing the unit tests for TodoInput.js has been relatively straightforward:
TodoInput.js:
handleChange(e) {
this.setState({ text: e.target.value });
}
...
render() {
return (
<input type="text" autoFocus='true'
className={classnames({
edit: this.props.editing,
'new-todo': this.props.newTodo
})}
value={this.state.text}
placeholder={this.props.placeholder}
onKeyDown={this.handleKeyDown.bind(this)}
onBlur={this.handleBlur.bind(this)}
onChange={this.handleChange.bind(this)}>
</input>
);
}
TodoInput-test.js:
const mockedTodo = {
text: 'abc123',
complete: false
};
it(`should update text from user input`, () => {
const component = TestUtils.renderIntoDocument(
<TodoInput
text = {mockedTodo.text}
editing = {false}
onSave = {_.noop}
/>
);
const inputComponent = TestUtils.findRenderedDOMComponentWithTag(component, 'input');
expect(React.findDOMNode(inputComponent).value).toBe(mockedTodo.text);
TestUtils.Simulate.change(React.findDOMNode(inputComponent), {target: {value: "newValue"}});
expect(React.findDOMNode(inputComponent).value).toBe("newValue");
React.unmountComponentAtNode(React.findDOMNode(component));
});
But for TodoItem.js, testing has been a little trickier.
The render code branches based on whether or not an editing flag has been set on the item:
TodoItem.js:
import React, { Component, PropTypes } from 'react';
import TodoInput from './TodoInput';
import classnames from 'classnames';
export default class TodoItem extends Component {
static propTypes = {
todo: PropTypes.object.isRequired,
editTodo: PropTypes.func.isRequired,
markTodoAsComplete: PropTypes.func.isRequired,
deleteTodo: PropTypes.func.isRequired
}
constructor(props, context) {
super(props, context);
this.state = {
editing: false
};
}
handleDoubleClick() {
this.setState({ editing: true });
}
handleSave(id, text) {
if (text.length === 0) {
this.props.deleteTodo(id);
} else {
this.props.editTodo(id, text);
}
this.setState({ editing: false });
}
render() {
const {todo, markTodoAsComplete, deleteTodo} = this.props;
let element;
if (this.state.editing) {
element = (
<TodoInput text={todo.text}
editing={this.state.editing}
onSave={(text) => this.handleSave(todo.id, text)} />
);
} else {
element = (
<div className='view'>
<label onDoubleClick={this.handleDoubleClick.bind(this)}>
{todo.text}
</label>
<input className='markComplete'
type='checkbox'
checked={todo.complete}
onChange={() => markTodoAsComplete(todo)} />
<button className='destroy'
onClick={() => deleteTodo(todo)} />
</div>
);
}
return (
<li className={classnames({
completed: todo.complete,
editing: this.state.editing
})}>
{element}
</li>
)
}
}
I'm a little stumped on how to go about writing a test that, for instance, would verify that a double-click on the component had successfully set the state to editing: true.
Typically, I have my tests divided into two parts, "rendering" and "events", i.e. for TodoItem-test.js:
import React, { addons } from 'react/addons';
import _ from 'lodash';
import expect from 'expect';
const { TestUtils } = addons;
import TodoItem from '../TodoItem';
describe('TodoItem', () => {
const mockedTodo = {
text: 'abc123',
complete: false
};
describe('rendering', () => {
let component;
before(() => {
component = TestUtils.renderIntoDocument(
<TodoItem
todo={mockedTodo}
editTodo={_.noop}
markTodoAsComplete={_.noop}
deleteTodo={_.noop}
/>
);
});
afterEach(() => {
React.unmountComponentAtNode(React.findDOMNode(component));
});
it('should render the element', () => {
const liComponent = TestUtils.findRenderedDOMComponentWithTag(component, 'li');
expect(liComponent).toExist();
});
it('should render text in label', () => {
const labelComponent = TestUtils.findRenderedDOMComponentWithTag(component, 'label');
expect(labelComponent).toExist();
expect(React.findDOMNode(labelComponent).textContent).toEqual('abc123');
});
});
describe('events', () => {
...
});
but in this case, I want to see if double-clicking on the component leads to the following:
the component state should now have an editing flag associated with it
the element should have changed, and TodoItem.js should now render a <TodoInput/> component instead.
What is the most efficient way to structure a test against this expected behavior? I am thinking that I should do two things:
First, test to see if a double-click on the component adds the expected "editing: true" flag. I am not sure how to do this. If I set up a test as follows:
describe('events', () => {
let component;
let deleteTodoCallback = sinon.stub();
beforeEach(() => {
component = TestUtils.renderIntoDocument(
<TodoItem
todo={mockedTodo}
editTodo={_.noop}
markTodoAsComplete={_.noop}
deleteTodo={deleteTodoCallback}
/>
);
});
afterEach(() => {
React.unmountComponentAtNode(React.findDOMNode(component));
});
it(`should change the editing state to be true if a user double-clicks
on the todo`, () => {
const liComponent = TestUtils.findRenderedDOMComponentWithTag(component, 'li');
// expect the editing flag to be false
TestUtils.Simulate.doubleClick(React.findDOMNode(liComponent));
// expect the editing flag to be true
});
});
how do I go about testing to ensure that the editing flag has been set? liComponent.props.editing returns undefined.
Second, have a context("if the component is editing mode") that tests to make sure that the following has been rendered correctly:
<li className={classnames({
completed: todo.complete,
editing: this.state.editing
})}>
<TodoInput text={todo.text}
editing={this.state.editing}
onSave={(text) => this.handleSave(todo.id, text)} />
</li>
I'm also not sure how I would go about testing this rigorously as well.
liComponent.props is undenfined because liComponent is a DOM element, not a react component. That's the case because you're fetching it with findRenderedDOMComponentWithTag. You actually already have access to the React component you're trying to test against.
it('should render the element', () => {
const liComponent = TestUtils.findRenderedDOMComponentWithTag(component, 'li');
// `component` is from your `before` function
expect(component.state.editing).toBe(false);
// Make sure you're simulating on a DOM element
TestUtils.Simulate.doubleClick(liComponent);
expect(component.state.editing).toBe(true);
});
You can then use scryRenderedComponentsWithType to check whether a TodoInput is rendered.

Categories

Resources