Poll model - validate end events

spec/test-utils/client.ts

@@ -60,6 +60,7 @@ export const getMockClientWithEventEmitter = (
  */
 export const mockClientMethodsUser = (userId = "@alice:domain") => ({
     getUserId: jest.fn().mockReturnValue(userId),
+    getSafeUserId: jest.fn().mockReturnValue(userId),
     getUser: jest.fn().mockReturnValue(new User(userId)),
     isGuest: jest.fn().mockReturnValue(false),
     mxcUrlToHttp: jest.fn().mockReturnValue("mock-mxcUrlToHttp"),

spec/unit/models/poll.spec.ts

@@ -38,6 +38,7 @@ describe("Poll", () => {
     const basePollStartEvent = new MatrixEvent({
         ...PollStartEvent.from("What?", ["a", "b"], M_POLL_KIND_DISCLOSED.name).serialize(),
         room_id: roomId,
+        sender: userId,
     });
     basePollStartEvent.event.event_id = "$12345";
 
@@ -155,7 +156,7 @@ describe("Poll", () => {
                 expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
             });
 
-            it("does not set poll end event when sent by invalid user", async () => {
+            it("does not set poll end event when sent by a user without redaction rights", async () => {
                 const poll = new Poll(basePollStartEvent, mockClient, room);
                 maySendRedactionForEventSpy.mockReturnValue(false);
                 jest.spyOn(poll, "emit");
@@ -166,6 +167,21 @@ describe("Poll", () => {
                 expect(poll.emit).not.toHaveBeenCalledWith(PollEvent.End);
             });
 
+            it("sets poll end event when current user created the poll, but does not have redaction rights", async () => {
+                const poll = new Poll(basePollStartEvent, mockClient, room);
+                const pollEndEvent = makeRelatedEvent({ type: M_POLL_END.stable!, sender: userId });
+                mockClient.relations.mockResolvedValue({
+                    events: [pollEndEvent],
+                });
+                maySendRedactionForEventSpy.mockReturnValue(false);
+                jest.spyOn(poll, "emit");
+                await poll.getResponses();
+
+                expect(maySendRedactionForEventSpy).not.toHaveBeenCalled();
+                expect(poll.isEnded).toBe(true);
+                expect(poll.emit).toHaveBeenCalledWith(PollEvent.End);
+            });
+
             it("sets poll end event with unstable event type", async () => {
                 mockClient.relations.mockResolvedValue({
                     events: [unstablePollEndEvent],

src/models/poll.ts

@@ -189,10 +189,14 @@ export class Poll extends TypedEventEmitter<Exclude<PollEvent, PollEvent.New>, P
         /**
          * MSC3381
          * If a m.poll.end event is received from someone other than the poll creator or user with permission to redact
-         * other's messages in the room, the event must be ignored by clients due to being invalid.
+         * others' messages in the room, the event must be ignored by clients due to being invalid.
          */
         const roomCurrentState = this.room.currentState;
         const endEventSender = endEvent.getSender();
-        return !!endEventSender && roomCurrentState.maySendRedactionForEvent(this.rootEvent, endEventSender);
+        return (
+            !!endEventSender &&
+            (endEventSender === this.matrixClient.getSafeUserId() ||
+                roomCurrentState.maySendRedactionForEvent(this.rootEvent, endEventSender))
+        );
     }
 }