Bug: [TS] No overload matches this call.

Describe the bug

When using as middleware typescript complains about the ValidationChain not being assignable to a RequestHandler

const getCertificateValidation = [
  query('data')
    .not()
    .isEmpty()
    .trim()
    .isBase64()
    .customSanitizer((value) => JSON.parse(Buffer.from(value, 'base64').toString()))
    .isJSON(),
];

routes.get('/investors/certificate', getCertificateValidation, getCertificate);

Error in full:

No overload matches this call.
  Overload 1 of 3, '(path: PathParams, ...handlers: RequestHandler<null, any, null, SanitisedQueryData>[]): Router', gave the following error.
    Argument of type 'ValidationChain[]' is not assignable to parameter of type 'RequestHandler<null, any, null, SanitisedQueryData>'.
      Type 'ValidationChain[]' provides no match for the signature '(req: Request<null, any, null, SanitisedQueryData>, res: Response<any, number>, next: NextFunction): any'.
  Overload 2 of 3, '(path: PathParams, ...handlers: RequestHandlerParams<Record<string, any> | undefined, any, null, SanitisedQueryData>[]): Router', gave the following error.
    Argument of type '(req: Request<null, null, null, SanitisedQueryData>, res: Response) => Promise<void>' is not assignable to parameter of type 'RequestHandlerParams<Record<string, any> | undefined, any, null, SanitisedQueryData>'.
      Type '(req: Request<null, null, null, SanitisedQueryData>, res: Response) => Promise<void>' is not assignable to type 'RequestHandler<Record<string, any> | undefined, any, null, SanitisedQueryData>'.
        Types of parameters 'req' and 'req' are incompatible.
          Type 'Request<Record<string, any> | undefined, any, null, SanitisedQueryData>' is not assignable to type 'Request<null, null, null, SanitisedQueryData>'.
            Types of property 'params' are incompatible.
              Type 'Record<string, any> | undefined' is not assignable to type 'null'.
                Type 'undefined' is not assignable to type 'null'.

Express-validator version:

• Version: 6.8.0

[moshie]

Will do can’t say I’ll get to it today but sometime this week.

[fedeci]

Thanks!