Keep getting ESLint "defined but never used.(no-unused-vars)" when defined

Question

I am using WebStorm IDE for my TypeScript project with ESLint and Prettier enabled. I am getting warning:

for this code:

import { ToastAndroid } from 'react-native';
import { TProjectsList, IProject } from '../types';

export const reduceRecursively = (data: IProject[]): TProjectsList => {
  return data.reduce((acc: TProjectsList, val: IProject) => {
    acc[val.id] = val;
    for (let key in val) {
      if (val.hasOwnProperty(key) && Array.isArray(val[key])) {
        val[key] = reduceRecursively(val[key]);
      }
    }
    return acc;
  }, {});
};

There are deffinitely both TProjectsList, IProject used here, so why I am getting this warning? Possible bug?

Answer 1

It was caused by my mistake.

My file was still *.js what causing some weird behaviour for ESLint!

Makre sure your file is *.ts / *.tsx!