Function checkGuards

packages/router/src/operators/check_guards.ts:56–78

(
  forwardEvent?: (evt: Event) => void,
)

import {takeUntilAbort} from '../utils/abort_signal_to_observable';

export function checkGuards(
  forwardEvent?: (evt: Event) => void,
): MonoTypeOperatorFunction<NavigationTransition> {
  return mergeMap((t) => {
    const {
      targetSnapshot,
      currentSnapshot,
      guards: {canActivateChecks, canDeactivateChecks},
    } = t;
    if (canDeactivateChecks.length === 0 && canActivateChecks.length === 0) {
      return of({...t, guardsResult: true});
    }

    return runCanDeactivateChecks(canDeactivateChecks, targetSnapshot!, currentSnapshot).pipe(
      mergeMap((canDeactivate) => {
        return canDeactivate && isBoolean(canDeactivate)
          ? runCanActivateChecks(targetSnapshot!, canActivateChecks, forwardEvent)
          : of(canDeactivate);
      }),
      map((guardsResult) => ({...t, guardsResult})),
    );
  });
}

function runCanDeactivateChecks(
  checks: CanDeactivate[],