Type error with options in Date.prototype.toLocaleDateString()

Question

The following code is causing a TypeScript error, but is working correctly:

components.push(expirationDate.toLocaleDateString(undefined, { dateStyle: 'long' }));

Error:(31, 74) TS2345: Argument of type '{ dateStyle: string; }' is not assignable to parameter of type 'DateTimeFormatOptions'.
  Object literal may only specify known properties, and 'dateStyle' does not exist in type 'DateTimeFormatOptions'.

I do see that dateStyle is indeed not included in Intl.DateTimeFormatOptions (which is the type for the options object:

    toLocaleDateString(locales?: string | string[], options?: Intl.DateTimeFormatOptions): string;
    ...
    interface DateTimeFormatOptions {
        localeMatcher?: string;
        weekday?: string;
        era?: string;
        year?: string;
        month?: string;
        day?: string;
        hour?: string;
        minute?: string;
        second?: string;
        timeZoneName?: string;
        formatMatcher?: string;
        hour12?: boolean;
        timeZone?: string;
    }

So, is there any way to fix this error without simply using //@ts-ignore?

Answer 1

Typescript appears to have added the dateStyle options amongst others in v4.2.

Here's the PR that introduced them: https://github.com/microsoft/TypeScript/pull/41880.

Upgrading to v4.2.3 fixed the Typescript error for me.