Comprehensive events emitter typing (#2034)

src/models/base-model.ts

@@ -1,51 +0,0 @@
-/*
-Copyright 2021 The Matrix.org Foundation C.I.C.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-import { EventEmitter } from "events";
-
-/**
- * Typed Event Emitter class which can act as a Base Model for all our model
- * and communication events.
- * This makes it much easier for us to distinguish between events, as we now need
- * to properly type this, so that our events are not stringly-based and prone
- * to silly typos.
- */
-export abstract class BaseModel<Events extends string> extends EventEmitter {
-    public on(event: Events, listener: (...args: any[]) => void): this {
-        super.on(event, listener);
-        return this;
-    }
-
-    public once(event: Events, listener: (...args: any[]) => void): this {
-        super.once(event, listener);
-        return this;
-    }
-
-    public off(event: Events, listener: (...args: any[]) => void): this {
-        super.off(event, listener);
-        return this;
-    }
-
-    public addListener(event: Events, listener: (...args: any[]) => void): this {
-        super.addListener(event, listener);
-        return this;
-    }
-
-    public removeListener(event: Events, listener: (...args: any[]) => void): this {
-        super.removeListener(event, listener);
-        return this;
-    }
-}

src/models/thread.ts

@@ -19,7 +19,7 @@ import { MatrixEvent } from "./event";
 import { EventTimeline } from "./event-timeline";
 import { EventTimelineSet } from './event-timeline-set';
 import { Room } from './room';
-import { BaseModel } from "./base-model";
+import { TypedEventEmitter } from "./typed-event-emitter";
 
 export enum ThreadEvent {
     New = "Thread.new",
@@ -30,7 +30,7 @@ export enum ThreadEvent {
 /**
  * @experimental
  */
-export class Thread extends BaseModel<ThreadEvent> {
+export class Thread extends TypedEventEmitter<ThreadEvent> {
     /**
      * A reference to the event ID at the top of the thread
      */

src/models/typed-event-emitter.ts

@@ -0,0 +1,83 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { EventEmitter } from "events";
+
+enum EventEmitterEvents {
+    NewListener = "newListener",
+    RemoveListener = "removeListener",
+}
+
+/**
+ * Typed Event Emitter class which can act as a Base Model for all our model
+ * and communication events.
+ * This makes it much easier for us to distinguish between events, as we now need
+ * to properly type this, so that our events are not stringly-based and prone
+ * to silly typos.
+ */
+export abstract class TypedEventEmitter<Events extends string> extends EventEmitter {
+    public addListener(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.addListener(event, listener);
+    }
+
+    public emit(event: Events | EventEmitterEvents, ...args: any[]): boolean {
+        return super.emit(event, ...args);
+    }
+
+    public eventNames(): (Events | EventEmitterEvents)[] {
+        return super.eventNames() as Events[];
+    }
+
+    public listenerCount(event: Events | EventEmitterEvents): number {
+        return super.listenerCount(event);
+    }
+
+    public listeners(event: Events | EventEmitterEvents): Function[] {
+        return super.listeners(event);
+    }
+
+    public off(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.off(event, listener);
+    }
+
+    public on(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.on(event, listener);
+    }
+
+    public once(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.once(event, listener);
+    }
+
+    public prependListener(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.prependListener(event, listener);
+    }
+
+    public prependOnceListener(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.prependOnceListener(event, listener);
+    }
+
+    public removeAllListeners(event?: Events | EventEmitterEvents): this {
+        return super.removeAllListeners(event);
+    }
+
+    public removeListener(event: Events | EventEmitterEvents, listener: (...args: any[]) => void): this {
+        return super.removeListener(event, listener);
+    }
+
+    public rawListeners(event: Events | EventEmitterEvents): Function[] {
+        return super.rawListeners(event);
+    }
+}

src/store/local-storage-events-emitter.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { BaseModel } from "../models/base-model";
+import { TypedEventEmitter } from "../models/typed-event-emitter";
 
 export enum LocalStorageErrors {
     Global = 'Global',
@@ -33,5 +33,5 @@ export enum LocalStorageErrors {
  * maybe you should check out your disk, as it's probably dying and your session may die with it.
  * See: https://github.com/vector-im/element-web/issues/18423
  */
-class LocalStorageErrorsEventsEmitter extends BaseModel<LocalStorageErrors> {}
+class LocalStorageErrorsEventsEmitter extends TypedEventEmitter<LocalStorageErrors> {}
 export const localStorageErrorsEventsEmitter = new LocalStorageErrorsEventsEmitter();