Babel-eslint: 11.0.0-beta.0 - Typescript interface/type no-undef error

[prudolfs]

babel-eslint starting with version 11 uses babel config. That's great because now it possible to use babel-eslint with @babel/preset-typescript. AFAIK @babel/preset-typescript just strips away typescript types. However, running lint does not work for typescript interfaces/types because it throws no-undef error. Simple example how to reproduce will throw 5 error

* 5:18   error  'IValue' is not defined  no-undef
* 6:3    error  'a' is not defined       no-undef
* 7:3    error  'b' is not defined       no-undef
* 10:13  error  'Value' is not defined   no-undef
* 10:21  error  'IValue' is not defined  no-undef

[manuelbieh]

The link you shared is not public but I probably have the very same error:

type Foo = 'string';
const foo: Foo = 'foo';

results in an error:

   1:6   error  'Foo' is not defined                           no-undef

Any change to get babel-eslint to understand things like type or interface?

[pleunv]

Running into the same issue... Has anyone found any workaround by any chance?

[manuelbieh]

Yes. I'm using @typescript-eslint parser for .ts and .tsx files and disabled no-undef in TypeScript files as undefined variables are covered by TypeScript anyway:
https://github.com/wiremore/eslint-config-wiremore/blob/master/typescript.js

Works fine for me!

[joeldenning]

Also running into this issue. Would rather not turn off no-undef or switch to typescript-elint instead of babel-eslint + @babel/preset-typescript

[joeldenning]

This seems maybe related: https://github.com/typescript-eslint/typescript-eslint#what-about-babel-and-babel-eslint.

[kaicataldo]

Thank you for the issue. Now that @babel/eslint-parser has been released, we are making this repository read-only. If this is a change you would still like to advocate for, please reopen this in the babel/babel monorepo.