fix(router-lite): current route subscription disposal (#1969)

[skip ci]

packages/router-lite/src/configuration.ts

@@ -10,7 +10,6 @@ import { ViewportCustomElement } from './resources/viewport';
 import { LoadCustomAttribute } from './resources/load';
 import { HrefCustomAttribute } from './resources/href';
 import { IBaseHref, normalizePath } from './location-manager';
-import { _disposeCurrentRouteSubscription } from './current-route';
 
 export const RouterRegistration = IRouter as unknown as IRegistry;
 
@@ -71,10 +70,7 @@ function configure(container: IContainer, options?: IRouterConfigurationOptions)
     AppTask.creating(IRouter, _ => { /* ensure a router instance before the app root is instantiated and there by ensuring all the necessary aliases. */ }),
     AppTask.hydrated(IContainer, RouteContext.setRoot),
     AppTask.activated(IRouter, router => router.start(true)),
-    AppTask.deactivated(IRouter, router => {
-      _disposeCurrentRouteSubscription();
-      router.stop();
-    }),
+    AppTask.deactivated(IRouter, router => router.stop()),
     ...DefaultComponents,
     ...DefaultResources,
   );

packages/router-lite/src/current-route.ts

@@ -1,4 +1,4 @@
-import { DI, IDisposable, Writable, emptyArray, resolve } from '@aurelia/kernel';
+import { DI, Writable, emptyArray, resolve } from '@aurelia/kernel';
 import { RESIDUE } from '@aurelia/route-recognizer';
 import { batch } from '@aurelia/runtime';
 import { IRouter } from './router';
@@ -7,12 +7,6 @@ import { IRouterEvents } from './router-events';
 import type { Params, ViewportInstruction } from './instructions';
 import type { RouteConfig } from './route';
 
-let _currentRouteSubscription: IDisposable | null = null;
-/** @internal */
-export function _disposeCurrentRouteSubscription(): void {
-  _currentRouteSubscription?.dispose();
-}
-
 export const ICurrentRoute = /*@__PURE__*/ DI.createInterface<ICurrentRoute>('ICurrentRoute', x => x.singleton(CurrentRoute));
 export interface ICurrentRoute extends CurrentRoute { }
 
@@ -26,7 +20,11 @@ export class CurrentRoute {
   public constructor() {
     const router = resolve(IRouter);
     const options = router.options;
-    _currentRouteSubscription = resolve(IRouterEvents)
+    // In a realistic app, the lifetime of the CurrentRoute instance is the same as the app itself.
+    // Therefor the disposal of the subscription is avoided here.
+    // An alternative would be to introduce a new configuration option such that the router initializes this class in its constructor and also registers the class to container.
+    // Then the app task hooks of the router can be used directly to start/dispose the subscription.
+    resolve(IRouterEvents)
       .subscribe('au:router:navigation-end', (event) => {
         const vit = event.finalInstructions;
         batch(() => {