feat(alm): add alm.clear() method

Context: #1648 (comment)

Author: FaberVitale

packages/action-listener-middleware/src/index.ts

@@ -14,8 +14,6 @@ import type {
   BaseActionCreator,
   AnyActionListenerPredicate,
   CreateListenerMiddlewareOptions,
-  ConditionFunction,
-  ListenerPredicate,
   TypedActionCreator,
   TypedAddListener,
   TypedAddListenerAction,
@@ -200,6 +198,18 @@ export const createListenerEntry: TypedCreateListenerEntry<unknown> = (
   return entry
 }
 
+const createClearAllListeners = (listenerMap: Map<string, ListenerEntry>) => {
+  return () => {
+    listenerMap.forEach((entry) => {
+      entry.pending.forEach((controller) => {
+        controller.abort()
+      })
+    })
+
+    listenerMap.clear()
+  }
+}
+
 /**
  * Safely reports errors to the `errorHandler` provided.
  * Errors that occur inside `errorHandler` are notified in a new task.
@@ -491,6 +501,7 @@ export function createActionListenerMiddleware<
     {
       addListener,
       removeListener,
+      clear: createClearAllListeners(listenerMap),
       addListenerAction: addListenerAction as TypedAddListenerAction<S>,
     },
     {} as WithMiddlewareType<typeof middleware>

packages/action-listener-middleware/src/tests/listenerMiddleware.test.ts

@@ -492,6 +492,64 @@ describe('createActionListenerMiddleware', () => {
     })
   })
 
+  test('clear() cancels running listeners and removes all subscriptions', async () => {
+    const listener1Test = deferred()
+
+    let listener1Calls = 0
+    let listener2Calls = 0
+
+    middleware.addListener({
+      actionCreator: testAction1,
+      async listener(_, listenerApi) {
+        listener1Calls++
+        listenerApi.signal.addEventListener(
+          'abort',
+          () => listener1Test.resolve(listener1Calls),
+          { once: true }
+        )
+        await listenerApi.condition(() => true)
+        listener1Test.reject(new Error('unreachable: listener1Test'))
+      },
+    })
+
+    middleware.addListener({
+      actionCreator: testAction2,
+      listener() {
+        listener2Calls++
+      },
+    })
+
+    store.dispatch(testAction1('a'))
+
+    middleware.clear()
+    store.dispatch(testAction1('b'))
+    store.dispatch(testAction2('c'))
+
+    expect(listener2Calls).toBe(0)
+    expect(await listener1Test).toBe(1)
+  })
+
+  test('clear() cancels all running forked tasks', async () => {
+    const fork1Test = deferred()
+
+    middleware.addListener({
+      actionCreator: testAction1,
+      async listener(_, { fork }) {
+        const taskResult = await fork(() => {
+          return 3
+        }).result
+        fork1Test.resolve(taskResult)
+      },
+    })
+
+    store.dispatch(testAction1('a'))
+
+    middleware.clear()
+    store.dispatch(testAction1('b'))
+
+    expect(await fork1Test).toHaveProperty('status', 'cancelled')
+  })
+
   describe('Listener API', () => {
     test('Passes both getState and getOriginalState in the API', () => {
       const store = configureStore({

packages/action-listener-middleware/src/types.ts

@@ -218,6 +218,10 @@ export type ActionListenerMiddleware<
   addListener: AddListenerOverloads<Unsubscribe, S, D>
   removeListener: RemoveListenerOverloads<S, D>
   addListenerAction: TypedAddListenerAction<S, D>
+  /**
+   * Removes all subscribed listeners, cancels running listeners and tasks.
+   */
+  clear: () => void
 }
 
 /**