openUrl requires a returned promise, but why?

[eddiemonge]

Describe the problem

In version 2.x.x, why does openUrl as a function, require a returned promise? The example shows it returning void, which doesn't need to be resolved in a promise.

* @example
   * await auth0.logout({
   *   async openUrl(url) {
   *     window.location.replace(url);
   *   }
   * });
   */
  openUrl?: false | ((url: string) => Promise<void>);

[frederikprijck]

Hello,

This is because some integrations will return a promise, such as Capacitor's Browser.open.

Typically, opening a browser is an async operation, but not when using window.location.replace.
However, when you take control over opening the URL, our SDK will wait until the returned promise is resolved.

The example shows it returning void, which doesn't need to be resolved in a promise.

An async function that does not return anything will return a Promise<void>, not void.

This is exactly what is happening in the example you linked, it's an async function not returning anything.

[eddiemonge]

I meant the example does not need to be an async function since it returns void. By changing the type to

openUrl?: false | ((url: string) => Promise<void> | void)

and then the implementation to support that (which might be as simple as openUrl === false || Promise.resolve(openUrl), it would make the consumer's leaves slightly easier since they can do a normal callback or a promise based callback.

[eddiemonge]

Thank you all!