vkrol / typescript-eslint-no-unnecessary-type-assertion-undefined

https://github.com/typescript-eslint/typescript-eslint/issues/529

typescript-eslint-no-unnecessary-type-assertion-undefined

typescript-eslint/typescript-eslint#529

Steps

1. Run npm install or yarn
2. Run npm run typecheck or yarn typecheck -> no errors
3. Run npm run lint or yarn lint

D:\Projects\typescript-eslint-no-unnecessary-type-assertion-undefined\index.ts
  4:5  error  This assertion is unnecessary since the receiver accepts the original type of the expression  @typescript-eslint/no-unnecessary-type-assertion

✖ 1 problem (1 error, 0 warnings)
  1 error and 0 warnings potentially fixable with the `--fix` option.

4. Run npm run fix or yarn fix
5. Run npm run typecheck or yarn typecheck

index.ts:4:5 - error TS2345: Argument of type 'string | null' is not assignable to parameter of type 'string | undefined'.
  Type 'null' is not assignable to type 'string | undefined'.

4 foo(str);
      ~~~


Found 1 error.