Clear state on teardown, make grace optional (#377)

Author: bramkragten

lib/collection.ts

@@ -27,7 +27,8 @@ export const getCollection = <State>(
   subscribeUpdates?: (
     conn: Connection,
     store: Store<State>
-  ) => Promise<UnsubscribeFunc>
+  ) => Promise<UnsubscribeFunc>,
+  options: { unsubGrace: boolean } = { unsubGrace: true }
 ): Collection<State> => {
   if (conn[key]) {
     return conn[key];
@@ -93,6 +94,7 @@ export const getCollection = <State>(
       unsubProm.then((unsub) => {
         unsub();
       });
+    store.clearState();
     conn.removeEventListener("ready", refresh);
     conn.removeEventListener("disconnected", handleDisconnect);
   };
@@ -149,7 +151,9 @@ export const getCollection = <State>(
         }
 
         if (!active) {
-          scheduleTeardownUpdateSubscription();
+          options.unsubGrace
+            ? scheduleTeardownUpdateSubscription()
+            : teardownUpdateSubscription();
         }
       };
     },

lib/store.ts

@@ -15,6 +15,7 @@ export type Store<State> = {
   state: State | undefined;
   action(action: Action<State>): BoundAction<State>;
   setState(update: Partial<State>, overwrite?: boolean): void;
+  clearState(): void;
   subscribe(listener: Listener<State>): UnsubscribeFunc;
 };
 
@@ -82,12 +83,16 @@ export const createStore = <State>(state?: State): Store<State> => {
      */
     setState,
 
+    clearState() {
+      state = undefined;
+    },
+
     /**
      * Register a listener function to be called whenever state is changed. Returns an `unsubscribe()` function.
      * @param {Function} listener	A function to call when state changes. Gets passed the new state.
      * @returns {Function} unsubscribe()
      */
-    subscribe(listener: Listener<State>) {
+    subscribe(listener: Listener<State>): UnsubscribeFunc {
       listeners.push(listener);
       return () => {
         unsubscribe(listener);