Delete the room when it is forgotten and fire a new experimental event

lib/client.js

@@ -1478,13 +1478,27 @@ MatrixClient.prototype.ban = function(roomId, userId, reason, callback) {
 
 /**
  * @param {string} roomId
+ * @param {boolean} deleteRoom True to delete the room from the store on success.
+ * Default: true.
  * @param {module:client.callback} callback Optional.
  * @return {module:client.Promise} Resolves: TODO
  * @return {module:http-api.MatrixError} Rejects: with an error response.
  */
-MatrixClient.prototype.forget = function(roomId, callback) {
-    return _membershipChange(this, roomId, undefined, "forget", undefined,
+MatrixClient.prototype.forget = function(roomId, deleteRoom, callback) {
+    if (deleteRoom === undefined) {
+        deleteRoom = true;
+    }
+    var promise = _membershipChange(this, roomId, undefined, "forget", undefined,
         callback);
+    if (!deleteRoom) {
+        return promise;
+    }
+    var self = this;
+    return promise.then(function(response) {
+        self.store.removeRoom(roomId);
+        self.emit("deleteRoom", roomId);
+        return response;
+    });
 };
 
 /**
@@ -2641,6 +2655,17 @@ module.exports.CRYPTO_ENABLED = CRYPTO_ENABLED;
  * });
  */
 
+ /**
+ * Fires whenever a Room is removed. This will fire when you forget a room.
+ * <strong>This event is experimental and may change.</strong>
+ * @event module:client~MatrixClient#"deleteRoom"
+ * @param {string} roomId The deleted room ID.
+ * @example
+ * matrixClient.on("deleteRoom", function(roomId){
+ *   // update UI from getRooms()
+ * });
+ */
+
 /**
  * Fires whenever an incoming call arrives.
  * @event module:client~MatrixClient#"Call.incoming"

lib/store/memory.js

@@ -73,6 +73,14 @@ module.exports.MatrixInMemoryStore.prototype = {
         return utils.values(this.rooms);
     },
 
+    /**
+     * Permanently delete a room.
+     * @param {string} roomId
+     */
+    removeRoom: function(roomId) {
+        delete this.rooms[roomId];
+    },
+
     /**
      * Retrieve a summary of all the rooms.
      * @return {RoomSummary[]} A summary of each room.

lib/store/stub.js

@@ -54,6 +54,14 @@ StubStore.prototype = {
         return [];
     },
 
+    /**
+     * Permanently delete a room.
+     * @param {string} roomId
+     */
+    removeRoom: function(roomId) {
+        return;
+    },
+
     /**
      * No-op.
      * @return {Array} An empty array.