TypeScript errors due to missing @types/react-dom and @types/webpack when using "strict": true and "skipLibCheck": false

[elliottsj]

Bug report

Describe the bug

When setting tsconfig.json options "skipLibCheck": false and "strict": true, TypeScript errors are raised due to missing dependencies @types/react-dom and @types/webpack.

As a workaround, a Next.js project can declare these as dependencies in package.json, but this shouldn't be necessary.

To Reproduce

First, initialize a Next.js app with TypeScript:

$ npx create-next-app@9.5.2 my-app
...
$ cd my-app
$ touch tsconfig.json
$ npm run build

> my-app@0.1.0 build /Users/spencerelliott/Dev/elliottsj/my-app
> next build

It looks like you're trying to use TypeScript but do not have the required package(s) installed.

Please install typescript, @types/react, and @types/node by running:

	npm install --save-dev typescript @types/react @types/node

If you are not trying to use TypeScript, please remove the tsconfig.json file from your package root (and any TypeScript files in your pages directory).

$ npm install --save-dev typescript @types/react @types/node
$ npm run build
... (success)

Then edit tsconfig.json: set "strict": true and "skipLibCheck": false. Try building again:

$ npm run build

> my-app@0.1.0 build /Users/spencerelliott/Dev/elliottsj/my-app
> next build

Failed to compile.

./node_modules/next/types/index.d.ts:3:23
Type error: Cannot find type definition file for 'react-dom'.

  1 | /// <reference types="node" />
  2 | /// <reference types="react" />
> 3 | /// <reference types="react-dom" />
    |                       ^
  4 |
  5 | import React from 'react'
  6 | import { ParsedUrlQuery } from 'querystring'

Install @types/react-dom as a workaround and this error is resolved, but there's a new error:

$ npm install --save-dev @types/react-dom
...
$ npm run build

> my-app@0.1.0 build /Users/spencerelliott/Dev/elliottsj/my-app
> next build

Failed to compile.

./node_modules/next/dist/build/webpack/plugins/pages-manifest-plugin.d.ts:1:34
Type error: Could not find a declaration file for module 'webpack'. '/Users/spencerelliott/Dev/elliottsj/my-app/node_modules/webpack/lib/webpack.js' implicitly has an 'any' type.
  Try `npm install @types/webpack` if it exists or add a new declaration (.d.ts) file containing `declare module 'webpack';`

> 1 | import { Compiler, Plugin } from 'webpack';
    |                                  ^
  2 | export declare type PagesManifest = {
  3 |     [page: string]: string;
  4 | };

Install @types/webpack, then we get a successful build:

$ npm install --save-dev @types/webpack
...
$ npm run build

> my-app@0.1.0 build /Users/spencerelliott/Dev/elliottsj/my-app
> next build

info  - Creating an optimized production build
info  - Compiled successfully
info  - Collecting page data
info  - Generating static pages (2/2)
info  - Finalizing page optimization

Page                                                           Size     First Load JS
┌ ○ /                                                          3.42 kB        61.1 kB
├   └ css/a181cbd139209b03ddcc.css                             716 B
├   /_app                                                      0 B            57.7 kB
├ ○ /404                                                       3.45 kB        61.2 kB
└ λ /api/hello                                                 0 B            57.7 kB
+ First Load JS shared by all                                  57.7 kB
  ├ chunks/f6078781a05fe1bcb0902d23dbbb2662c8d200b3.e68a13.js  10 kB
  ├ chunks/framework.085e84.js                                 40 kB
  ├ chunks/main.270a02.js                                      6.69 kB
  ├ chunks/pages/_app.81bed2.js                                281 B
  ├ chunks/webpack.ccf5ab.js                                   751 B
  └ css/a7d1b6e4789f5d2be852.css                               202 B

λ  (Server)  server-side renders at runtime (uses getInitialProps or getServerSideProps)
○  (Static)  automatically rendered as static HTML (uses no initial props)
●  (SSG)     automatically generated as static HTML + JSON (uses getStaticProps)
   (ISR)     incremental static regeneration (uses revalidate in getStaticProps)

Redirects

┌ source: /:path+/
├ destination: /:path+
└ permanent: true

Expected behavior

The Next.js app should build successfully without having to install @types/react-dom and @types/webpack.

System information

• OS: macOS
• Version of Next.js: 9.5.2
• Version of Node.js: 14.8.0

[joshmanders]

Any updates on this? I'm getting same error and find it weird that I have to have types available to build in production.

[JavierMartinz]

I'm getting the same error and had to disable NPM_ONLY_PRODUCTION

[mohd-akram]

This is still happening with Next 11, although only @types/react-dom is required.

[AshConnolly]

Still happening in Next 12. Any ideas?

[AshConnolly]

For others my solution was to install all packages, but prune dev dependencies after build like so:

npm ci 

npm run build 

npm prune --production 

npm run start

It works fine, but it It would be better if this error didn't occur and we could just do npm ci --production followed by build, without the error occurring.

[github-actions]

Please verify that your issue can be recreated with next@canary.

Why was this issue marked with the please verify canary label?

We noticed the provided reproduction was using an older version of Next.js, instead of canary.

The canary version of Next.js ships daily and includes all features and fixes that have not been released to the stable version yet. You can think of canary as a public beta. Some issues may already be fixed in the canary version, so please verify that your issue reproduces by running npm install next@canary and test it in your project, using your reproduction steps.

If the issue does not reproduce with the canary version, then it has already been fixed and this issue can be closed.

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[balazsorban44]

This issue has been automatically closed because it wasn't verified against next@canary. If you think it was closed by accident, please leave a comment. If you are running into a similar issue, please open a new issue with a reproduction. Thank you.

[github-actions]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.