Type error: Could not find a declaration file for module 'next/dist/compiled/webpack/webpack'

[elliottsj]

What version of Next.js are you using?

10.0.6-canary.6

What version of Node.js are you using?

14.15.4

What browser are you using?

N/A

What operating system are you using?

Linux

How are you deploying your application?

Vercel

Describe the Bug

When upgrading from v10.0.6-canary.0 to v10.0.6-canary.6, this error is raised:

./node_modules/.pnpm/next@10.0.6-canary.6_c39e9db791ea05e3ec4e0e74abb7a6b5/node_modules/next/dist/build/webpack/plugins/build-manifest-plugin.d.ts:1:25
Type error: Could not find a declaration file for module 'next/dist/compiled/webpack/webpack'. '/home/runner/work/elliott.dev/elliott.dev/node_modules/.pnpm/next@10.0.6-canary.6_c39e9db791ea05e3ec4e0e74abb7a6b5/node_modules/next/dist/compiled/webpack/webpack.js' implicitly has an 'any' type.
  Try `npm i --save-dev @types/next` if it exists or add a new declaration (.d.ts) file containing `declare module 'next/dist/compiled/webpack/webpack';`

> 1 | import { webpack } from 'next/dist/compiled/webpack/webpack';
    |                         ^
  2 | import { Rewrite } from '../../../lib/load-custom-routes';
  3 | export declare type ClientBuildManifest = Record<string, string[]>;
  4 | export default class BuildManifestPlugin {

See https://github.com/elliottsj/elliott.dev/pull/442/checks?check_run_id=1733030038

I am using pnpm, as well as tsconfig options "strict": true and "skipLibCheck": false.

Expected Behavior

No error should occur.

To Reproduce

See:

• https://github.com/elliottsj/elliott.dev
• https://github.com/elliottsj/elliott.dev/pull/442/checks?check_run_id=1733030038

[flybayer]

I'm seeing this too

[aralroca]

Same

[zEh-]

@guybedford, still doesn't work for me with or without webpack as (dev-)dep.
Anyone else having luck?

$ yarn why next
=> Found "next@10.0.7-canary.0"

$ yarn why webpack
=> Found "webpack@4.46.0"

$ next build
../../node_modules/next/dist/build/webpack/plugins/build-manifest-plugin.d.ts:1:25
Type error: Could not find a declaration file for module 'next/dist/compiled/webpack/webpack'. '[...]/node_modules/next/dist/compiled/webpack/webpack.js' implicitly has an 'any' type.
  Try `npm i --save-dev @types/next` if it exists or add a new declaration (.d.ts) file containing `declare module 'next/dist/compiled/webpack/webpack';`

> 1 | import { webpack } from 'next/dist/compiled/webpack/webpack';
    |                         ^
  2 | import { Rewrite } from '../../../lib/load-custom-routes';
  3 | export declare type ClientBuildManifest = Record<string, string[]>;
  4 | export default class BuildManifestPlugin {
info  - Creating an optimized production build .child_process.js:655
    throw err;
    ^

[flybayer]

Workaround, add this in your code somewhere:

declare namespace webpack {
   export type Compiler = any
   export type Plugin = any
 }
 declare module "next/dist/compiled/webpack/webpack" {
   export const webpack: any
 }

[heavenshell]

When I set "skipLibCheck": false on tsconfig.json,
Type error: Could not find a declaration file for module 'next/dist/compiled/webpack/webpack' raised.
If I set "skipLibCheck": true works fine.

Should I always set "skipLibCheck": true?
I'd like set always skipLibCheck: false.

[guybedford]

If the previous PR didn't capture the issue, perhaps someone here can share a full end to end replication for me as I wasn't able to replicate the issue with a basic app with a tsconfig.json as described. @elliottsj I also tried cloning your repo but wasn't able to see the issue there either.

Alternatively, could someone here verify if the approach in guybedford@39e7ffd seems like it might work, in which case we could go ahead and merge that.

[elliottsj]

@guybedford

git clone https://github.com/elliottsj/elliott.dev.git
cd elliott.dev/
git checkout next-10.0.7
# npm i -g pnpm
pnpm i
pnpm build

Tried the approach in guybedford@39e7ffd, but the error persists. This is also raised:

[guybedford]

Thanks @elliottsj that was exactly the replication I needed, I've verified the fix in #21785 works against that case.

[balazsorban44]

This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.