After enabling the strictFunctionTypes check in my Angular 11.1.1 project, I encountered an issue with a function that uses RxJs combineLatest. The type passed to the subscription remains an array and is not automatically destructured into individual variables, causing an error.
Disabling strictFunctionTypes resolves the issue, but I'm looking for a way to refactor the code to adhere to the strictFunctionTypes rule.
combineLatest([
this.user$.pipe(startWith(null as User)),
this.order$.pipe(startWith(null as Order)),
this.invoice$.pipe(startWith([] as Faktura[])),
this.document$.pipe(startWith([] as Document[]))
]).pipe(
tap(([ order, user, invoices, docs ]: [ Partner, User, Faktura[], Document[]]) => {
this.ordersCache$.next(order);
this.usersCache$.next(user);
this.invoicesCache$.next(invoices);
this.docsCache$.next(docs);
}),
catchError(() => of([
this.ordersCache$.value,
this.usersCache$.value,
this.invoicesCache$.value,
this.docsCache$.value,
])),
takeUntil(this.destroy$)
).subscribe({
// The type is (Order | User | Faktura[] | Document[])[] and does not
// automatically destructure it into the single entities.
// This make the strictFunctionTypes rule fail as it does
// not match the given parameter
next: ([ order, user, invoices, docs ]: [
Order,
User,
Faktura[],
Document[]
]) => {
// ...
},
error: (err) => {
throw new Error(err);
}
});
UPDATE
Upon trying kvetis suggestion of using tap instead of map and omitting the return, the error still persists:
https://i.sstatic.net/h3p9o.png
The ongoing issue seems to be related to the catchError block because when removed, the exception no longer occurs.