Typescript (tsc) cannot find modules from inside workspace

[jeffrson]

Describe the bug

From inside a workspace in my test project the typescript compiler cannot find a certain referenced module.

To Reproduce

See repo at https://github.com/jeffrson/yarn2_types.git

Environment if relevant (please complete the following information):

• OS: [e.g. OSX, Linux, Windows, ...] Windows 10
• Node version [e.g. 8.15.0, 10.15.1, ...] 13.7.0
• Yarn version [e.g. 2.0.0-rc1, ...] 2.0.0-rc28

Additional context

../../.yarn/$$virtual/subscriptions-transport-ws-virtual-de5b014bf6/0/cache/subscriptions-transport-ws-npm-0.9.16-e352bac494-1.zip/node_modules/subscriptions-transport-ws/dist/server.d.ts:2:28 - error TS7016: Could not find a declaration file for module 'ws'.
'c:/.../workspace/.yarn/cache/ws-npm-5.2.2-173bcd57b2-1.zip/node_modules/ws/index.js' implicitly has an 'any' type.
  Try `npm install @types/ws` if it exists or add a new declaration (.d.ts) file containing `declare module 'ws';`

2 import * as WebSocket from 'ws';
                             ~~~~


Found 2 errors.

command not found: tsc

[arcanis]

You're using subscriptions-transport-ws, which depends on ws (through here) and thus on @types/ws, but doesn't list @types/ws in either dependencies or peerDependencies (instead only listing it in devDependencies).

So basically your project is fine (you could call import ... from 'ws', the problem is the missing dependency in subscriptions-transport-ws.

As a workaround, use packageExtensions to declare the missing (peer?) dependency, and maybe send a PR upstream to let them know about the issue.

[jeffrson]

Thank you for the detailed explanation. Thanks also for the suggestion of workaround (which works).

OTOH, shouldn't the error occur without workspace as well?

[yarnbot]

Hi! 👋

This issue looks stale, and doesn't feature the reproducible label - which implies that you didn't provide a working reproduction using Sherlock. As a result, it'll be closed in a few days unless a maintainer explicitly vouches for it or you edit your first post to include a formal reproduction (you can use the playground for that).

Note that we require Sherlock reproductions for long-lived issues (rather than standalone git repositories or similar) because we're a small team. Sherlock gives us the ability to check which bugs are still affecting the master branch at any given point, and decreases the amount of code we need to run on our own machines (thus leading to faster bug resolution faster). It helps us help you! 😃

If you absolutely cannot reproduce a bug on Sherlock (for example because it's a Windows-only issue), a maintainer will have to manually add the upholded label.

[merceyz]

Closing as a upstream issue

OTOH, shouldn't the error occur without workspace as well?

Not if you have installed @types/ws as one of your own dependencies.