react How to test the timers - setTimeout and setInterval in react using enzyme Learn how to test the callback function inside setTimeout and setInterval in react. Use fake timers and advance timers to test the code. Use runOnlyPendingTimers to avoid infinite loop in setInterval.
react How to unit test the asynchronous code Axios or fetch library in React using enzyme Learn how to test the http API call using Axios library or fetch library. You will learn how to mock the API calls and wait for the state changes to be set.
react How to unit test state of the component using enzyme Learn how to test the state of the component by using enzyme. You will learn to access the instance methods of component and spy on its methods.
gatsby How to get started with Gatsby themes Learn about the usefulness of themes in Gatsby and how to create themes in Gatsby, and consume them.
react How to use error boundary in react? Learn about error boundary in react and how to use it using componentDidCatch and getDerivedStateFromError. Also, learn when to use one of the above methods.
react What are render phase and commit phase in react? Learn about render phase and commit phase methods to react. Also, learn when to use side-effects to React.
react Test Driven React Development using react testing library In this tutorial, we are going to look into testing react.js applications using React Testing Library. We are going to go though dom-testing-library and a simple example to showcase react-testing-library.
react Difference between brittle and non-brittle tests in React JS Learn the difference between brittle and non-brittle tests in reactjs. It is going to save your time in writing un-necessary tests.
react Difference between react-testing-library and enzyme Difference between react-testing-library and enzyme on setup, concept, forceUpdate or shallow/deep rendering of the component
adblock How Adblock works Learn how adblock blocks the ads from displaying or loading in website. We will look into what is EasyList, and a simple parser for EasyList.
react What is purecomponent in react How does purecomponent work and help in improving performance in react. Learn about false positives and changing the reference of object to prevent it.
chrome How to take full page screenshot in chrome in different resolutions How to take full page and device specific screenshot in chrome browser using the developer tools.
react Using list virtualizers or infinite list loader in react If you have a long list, then performance to render it can be improved by using pagination or infinite scrolling and windowing technique.
react-testing Testing routes (react router dom) in react using jest - 2 Learn how to test the routes in react. In part 2 of the post, we will look into testing the routes using the MemoryRouter object.
react-testing Testing routes (react router dom) in react using jest - 1 Learn how to test the routes in react. In part 1 of the post, we will look into testing the routes using an object of pathname and component name.
react Using production build in webpack to improve performance of react application Production builds have minified, uglified and obfuscated code. Due to this, the code size is lesser than the development. Using production build results in lesser payload transfer between server and client, and results in faster load of the application.
speech to text Speech to text using web speech api Speech to text has been around for a long time. There are many services available which can do the speech to text with amazing accuracy. Did you know that your chrome browser too can do the speech to text using web speech api? Yes you heard it right. Read below to find out more
react-testing Unit testing set timeout and setInterval functions in react Learn about testing timers like setTimeout and setInterval in react. Jest provides functions for faking timers, clearing timers and advancing timers.
chrome How to fix Chrome not showing cookies for cross origin requests in network pane Site isolation is a new feature in chrome. Disable site isolation to see the cookies in network pane in chrome.
javascript What does "this" refers to in javascript? The meaning of this is different in javascript in browser and in nodejs. this is also related to binding of context in functions.
npm What was security issue in popular npm package event-stream The malicious code injected into the popular stream library `event-stream` targeted specific users of `copay` service. Under specific conditions, it would then collect the victim's copay private keys, account data and send it some collection.
httpserver How to start http server at any folder http server can be used to run a http web server at any path. There are many configurations options available like ssl, port, address, gzip.
react How to sort items in react dnd (drag and drop) React dnd is a popular library for drag and drop in react. In this tutorial, we will learn how to sort the items manually using drag and drop. You can watch the video of sorting in youtube link as well. The complete demo of the code can be found at the bottom of the tutorial.
react Why do we have to call super(props) in constructor react? uper(props) is required to be called in constructor to access this.props. If it is not called in constructor, then `this.props` will be undefined in constructor.
expressjs What does express generator not provide by default Express generator does not provide the recommendations on handling post request, performance, security and testing
