Add failing test

tests-e2e/membership_transitions_test.go

@@ -397,6 +397,63 @@ func TestInviteRejectionTwice(t *testing.T) {
 	})
 }
 
+func TestLeavingRoomReturnsOneEvent(t *testing.T) {
+	alice := registerNewUser(t)
+	bob := registerNewUser(t)
+	roomName := "It's-a-me-invitio"
+	inviteRoomID := alice.CreateRoom(t, map[string]interface{}{"preset": "private_chat", "name": roomName})
+	t.Logf("TestLeavingRoomReturnsOneEvent room %s", inviteRoomID)
+
+	// sync as bob, we see no invites yet.
+	res := bob.SlidingSync(t, sync3.Request{
+		Lists: map[string]sync3.RequestList{
+			"a": {
+				Ranges: sync3.SliceRanges{{0, 20}},
+				Filters: &sync3.RequestFilters{
+					IsInvite: &boolTrue,
+				},
+			},
+		},
+	})
+	m.MatchResponse(t, res, m.MatchList("a", m.MatchV3Count(0)), m.MatchRoomSubscriptionsStrict(nil))
+
+	// now invite bob
+	alice.InviteRoom(t, inviteRoomID, bob.UserID)
+	// sync as bob until we see the room
+	res = bob.SlidingSyncUntilMembership(t, res.Pos, inviteRoomID, bob, "invite")
+	t.Logf("bob is invited")
+
+	// join the room
+	bob.JoinRoom(t, inviteRoomID, []string{})
+	res = bob.SlidingSyncUntilMembership(t, res.Pos, inviteRoomID, bob, "join")
+	t.Logf("bob joined")
+
+	// leave the room again, we should receive exactly one leave response
+	bob.LeaveRoom(t, inviteRoomID)
+	res = bob.SlidingSyncUntilMembership(t, res.Pos, inviteRoomID, bob, "leave")
+
+	if room, ok := res.Rooms[inviteRoomID]; ok {
+		if c := len(room.Timeline); c > 1 {
+			for _, ev := range res.Rooms[inviteRoomID].Timeline {
+				t.Logf("Event: %s", ev)
+			}
+			t.Fatalf("expected 1 timeline event, got %d", c)
+		}
+	} else {
+		t.Fatalf("expected room %s in response, but didn't find it", inviteRoomID)
+	}
+
+	res = bob.SlidingSync(t, sync3.Request{}, WithPos(res.Pos))
+
+	// this should not happen, as we already send down the leave event
+	if room, ok := res.Rooms[inviteRoomID]; ok {
+		for _, ev := range room.Timeline {
+			t.Logf("Event: %s", ev)
+		}
+		t.Fatalf("expected room not to be in response")
+	}
+}
+
 // test invite/join counts update and are accurate
 func TestMemberCounts(t *testing.T) {
 	alice := registerNewUser(t)