README.md

Why did you render

This is a simple example of how to use why-did-you-render within a Next.js app.

We are essentially extending webpack config to allow the monkey patched React version of WDYR in development mode and adding to our application by importing wdyr.ts at the top of Next.js _app.tsx.

By default, all pure components will be tracked, but you can add Component.whyDidYouRender = true to regular function components in case you need.

In this example, the header component will rerender despite the state staying the same.

You can see why-did-you-render console logs about this redundant re-render in the developer console.

When using Typescript, call the file wdyr.ts instead and add the following line to the top of the file to import the package's types:

/// <reference types="@welldone-software/why-did-you-render" />

Deploy your own

Deploy the example using Vercel or preview live with StackBlitz

How to use

Execute create-next-app with npm, Yarn, or pnpm to bootstrap the example:

npx create-next-app --example with-why-did-you-render with-why-did-you-render-app

yarn create next-app --example with-why-did-you-render with-why-did-you-render-app

pnpm create next-app --example with-why-did-you-render with-why-did-you-render-app

Deploy it to the cloud with Vercel (Documentation).