Imported types cause false positives with `no-unused-vars` rule

[Hilzu]

What version of TypeScript are you using?
2.7.2

What version of typescript-eslint-parser are you using?
14.0.0

What code were you trying to parse?

import { Server } from "http"
import app from "./app"

let server: Server | null = null

server = app.listen(() => {
  console.log("Listening on", server!.address())
})

What did you expect to happen?
No errors are reported with the no-unused-vars rule on

What happened?

src/test.ts
  1:10  error    'Server' is defined but never used  no-unused-vars

The no-unused-vars rule was previously mentioned in the readme as having known issues. Now that it's removed I expected the above code to work.

[kinyat]

We cannot turn on noUnusedLocals on local development as it is very annoying to have this blocking the complier.

Would really love to rely on eslint to check to allow compiling.

[tushar-singh]

I have this issue as well. Using the same workaround as kinyat via overrides (so I can still have these rules enabled in .js and .jsx files)

  "rules": { ... },
  "overrides": [
    {
      "files": ["**/*.ts", "**/*.tsx"],
      "rules": {
        "no-unused-vars": ["off"],
        "no-undef": ["off"]
      }
    }
  ]

[JamesHenry]

There is already a custom rule in the plugin for no-unused-vars: https://github.com/nzakas/eslint-plugin-typescript/blob/master/docs/rules/no-unused-vars.md

If that rule is no sufficient for this use-case then a bug report should be filed against it, and ideally a PR submitted to extend at.

Thanks!

[KaelWD]

I was using that, it fails if you import types that don't have a value.

'no-unused-vars': 'error',
'typescript/no-unused-vars': 'error',

// ERROR: 'Options' is defined but never used
import { VuetifyUseOptions as Options } from 'types'
...
// Even though I use it here as a type
export default function lang (config: Options['lang'] = {}): VuetifyLanguage {

[JamesHenry]

As per my previous message, a bug report should be filed against the plugin, this is not a parsing issue

[KaelWD]

Forgot this was a separate repo 😅

Looks like there is already a few:
nzakas/eslint-plugin-typescript#33
bradzacher/eslint-plugin-typescript#90
bradzacher/eslint-plugin-typescript#112