abarghoud ca721c2972 feat(core): more precise type for APP_INITIALIZER token (#40986)
This commit updates the type of the `APP_INITIALIZER` injection token to
better document the expected types of values that Angular handles. Only
Promises and Observables are awaited and other types of values are ignored,
so the type of `APP_INITIALIZER` has been updated to
`Promise<unknown> | Observable<unknown> | void` to reflect this behavior.

BREAKING CHANGE:

The type of the `APP_INITIALIZER` token has been changed to more accurately
reflect the types of return values that are handled by Angular. Previously,
each initializer callback was typed to return `any`, this is now
`Promise<unknown> | Observable<unknown> | void`. In the unlikely event that
your application uses the `Injector.get` or `TestBed.inject` API to inject
the `APP_INITIALIZER` token, you may need to update the code to account for
the stricter type.

Additionally, TypeScript may report the TS2742 error if the `APP_INITIALIZER`
token is used in an expression of which its inferred type has to be emitted
into a .d.ts file. To workaround this, an explicit type annotation is needed,
which would typically be `Provider` or `Provider[]`.

Closes #40729

PR Close #40986
2021-03-04 12:01:07 -08:00
..
2021-02-22 12:37:40 -08:00

Angular

The sources for this package are in the main Angular repo. Please file issues and pull requests against that repo.

Usage information and reference details can be found in Angular documentation.

License: MIT