I am trying to test my SEO component which looks like this: and my test is like so: however the test is failing: (it looks like the head element is empty) Answer I was having the same issue, but I found this answer on GitHub. So basically you need to mock next/head, pass document.head to the container property of render’s
Tag: reactjs
Webpack successfully builds, but JavaScript doesn’t execute runtime
I have migrated Webpack v4 to v5, made changes relative to documentation and deprecation messages from CLI, and got successful build, though during the application testing I noticed that JavaScript doesn’t run and there are no errors. I am getting plain html rendered by SSR. Have no clue why it doesn’t work, because it’s silent, maybe misconfiguration issue. Here is
Will React rerender if I use setState but the state value stay the same?
Say I have a React component with state {random: 1} currently. If I call does it trigger re-rendering? If it does, is there any way I can prevent the re-rendering when calling setState but the state does not change like this? Answer Yes, it will re-render: You can add a shouldComponentUpdate method to tell React not to re-render if the
How to immediatelly update Parent state inside Child components
I’m trying to immediatelly update a parent components’ state so I can properly use it in a Child (nested) component. I will try to give as many details as possible so you an understand. So basically I have a parent component (App.js): App.js (parent component) visual: This component has an array of objects (options) that is sent to the Child
Pseudo element not showing in React on paragraph tag despite using display block
This pseudo element ::after won’t show up in my browser at all. I am using React.js and Material UI makeStyles. This is the code: Note that the code below modalTitle shows up and works, only the pseudo element doesn’t go through. Any thoughts? Answer This is a tricky one. When you use makeStyles, it accepts a styles object (or a
Issue downloading string as text file
I am trying to download data gotten from a GET request as a .txt file but I keep getting ‘undefined’ as the content of the downloaded file. I only need the data portion of the response. A sample response is provided below as well as my redux action, reducer and my export function My action: my reducer: my download function:
React UseState truthy/falsy
I’m trying to initialize some state for my form component with data from the redux store. If the shippingAddress object is null, I want to set properties of formData object to empty strings. Not sure how to get it to work. Currently I am receiving an error message saying TypeError: Cannot read property ‘address’ of null Answer You could accomplish
Usestate increment by 1 not working in setInterval
For some reason this will never go past two when I run the setCurrentPage but if I increment it like this It works as expected. I am guessing it has something to do with the useEffect or the setInterval but not really a 100% sure why. Answer A new handleScroll function is created on every render in your code. The
How can I redirect newly created users to their “logged-in” homepage?
I am running a Django Rest backend with a React front-end. JSON data during user registration is being pushed per normal. When users submit the register form, they are sent to a login page. I realize how annoying this is for the users, however I’m not so sure how automatically send the user to the logged-in version of the homepage.
‘Illegal invocation’ using input setCustomValidity and TS
I’m pretty much new to Typescript world and am converting one of the first React applications. Here I’m trying to set custom messages on input validation by using event.target.setCustomValidity but I’m getting the ‘Illegal invocation’ error when the setCustomValidity function gets triggered. Here there is the sandbox; To trigger the error it’s just required to update the first input. Debugging