TypeScript/Eslint throwing a 'Promise returned' error on a Express Router async route

I have the following endpoint setup to reset a database after test runs:

import { getConnection } from 'typeorm';
import express from 'express';
const router = express.Router();

const resetDatabase = async (): Promise<void> => {
  const connection = getConnection();
  await connection.dropDatabase();
  await connection.synchronize();
};

// typescript-eslint throws an error in the following route:
router.post('/reset', async (_request, response) => {
  await resetTestDatabase();
  response.status(204).end();
});

export default router;

The entire route since async is underlined with a typescript-eslint error Promise returned in function argument where a void return was expected.

The app works perfectly but I'm not sure if I should be doing a safer implementation or just ignoring/disabling Eslint for this one. Any idea of what's wrong with that code?

It seems you are using the no-misused-promises rule which states that you cannot return Promise<void> in a place where void is expected.

This means that you cannot return Promise<void> from your Express handler because the return type of RequestHandler from the library specifies that the return type should be void. I would suggest that you change it to return Promise<Response> by adding a simple return keyword:

import { getConnection } from 'typeorm';
import express from 'express';
const router = express.Router();

const resetDatabase = async (): Promise<void> => {
  const connection = getConnection();
  await connection.dropDatabase();
  await connection.synchronize();
};

// typescript-eslint throws an error in the following route:
router.post('/reset', async (_request, response) => {
  await resetTestDatabase();
  return response.status(204).send();  // <----- return added here
});

export default router;

The other option would be to avoid using async/await:

router.post('/reset', (_request, response) => {
  resetDatabase().then(() => response.status(204).send());
});