Fix test

federationapi/routing/send.go

@@ -468,27 +468,19 @@ func (t *txnReq) processEventWithMissingState(ctx context.Context, e gomatrixser
 	// - fill in the gap completely then process event `e` returning no backwards extremity
 	// - fail to fill in the gap and tell us to terminate the transaction err=not nil
 	// - fail to fill in the gap and tell us to fetch state at the new backwards extremity, and to not terminate the transaction
-	newEvents, backwardsExtremity, err := t.getMissingEvents(gmectx, e, roomVersion, true)
+	newEvents, err := t.getMissingEvents(gmectx, e, roomVersion)
 	if err != nil {
 		return err
 	}
-	if backwardsExtremity == nil {
-		// we filled in the gap!
-		fmt.Println("No backwards extremity")
-		//return nil
-	}
 	if len(newEvents) == 0 {
-		fmt.Println("No new events")
 		return nil
 	}
 
-	backwardsExtremity = &newEvents[0]
+	backwardsExtremity := &newEvents[0]
 	newEvents = newEvents[1:]
 
 	fmt.Println(len(newEvents), "new events")
 
-	fmt.Println("GO!")
-
 	// at this point we know we're going to have a gap: we need to work out the room state at the new backwards extremity.
 	// Therefore, we cannot just query /state_ids with this event to get the state before. Instead, we need to query
 	// the state AFTER all the prev_events for this event, then apply state resolution to that to get the state before the event.
@@ -509,8 +501,6 @@ func (t *txnReq) processEventWithMissingState(ctx context.Context, e gomatrixser
 		states = append(states, prevState)
 	}
 
-	fmt.Println("CHECKPOINT 1")
-
 	// Now that we have collected all of the state from the prev_events, we'll
 	// run the state through the appropriate state resolution algorithm for the
 	// room. This does a couple of things:
@@ -523,8 +513,6 @@ func (t *txnReq) processEventWithMissingState(ctx context.Context, e gomatrixser
 		return err
 	}
 
-	fmt.Println("CHECKPOINT 2")
-
 	// First of all, send the backward extremity into the roomserver with the
 	// newly resolved state. This marks the "oldest" point in the backfill and
 	// sets the baseline state for any new events after this.
@@ -552,11 +540,10 @@ func (t *txnReq) processEventWithMissingState(ctx context.Context, e gomatrixser
 	if err = api.SendEvents(
 		context.Background(),
 		t.rsAPI,
-		headeredNewEvents,
+		append(headeredNewEvents, e.Headered(roomVersion)),
 		api.DoNotSendToOtherServers,
 		nil,
 	); err != nil {
-		fmt.Println("ERROR!", err)
 		return fmt.Errorf("api.SendEvents: %w", err)
 	}
 	fmt.Println("SUCCESS!")
@@ -717,11 +704,7 @@ retryAllowedState:
 // This function recursively calls txnReq.processEvent with the missing events, which will be processed before this function returns.
 // This means that we may recursively call this function, as we spider back up prev_events.
 // nolint:gocyclo
-func (t *txnReq) getMissingEvents(ctx context.Context, e gomatrixserverlib.Event, roomVersion gomatrixserverlib.RoomVersion, isInboundTxn bool) (newEvents []gomatrixserverlib.Event, backwardsExtremity *gomatrixserverlib.Event, err error) {
+func (t *txnReq) getMissingEvents(ctx context.Context, e gomatrixserverlib.Event, roomVersion gomatrixserverlib.RoomVersion) (newEvents []gomatrixserverlib.Event, err error) {
-	if !isInboundTxn {
-		// we've recursed here, so just take a state snapshot please!
-		return nil, &e, nil
-	}
 	logger := util.GetLogger(ctx).WithField("event_id", e.EventID()).WithField("room_id", e.RoomID())
 	needed := gomatrixserverlib.StateNeededForAuth([]gomatrixserverlib.Event{e})
 	// query latest events (our trusted forward extremities)
@@ -732,7 +715,7 @@ func (t *txnReq) getMissingEvents(ctx context.Context, e gomatrixserverlib.Event
 	var res api.QueryLatestEventsAndStateResponse
 	if err = t.rsAPI.QueryLatestEventsAndState(ctx, &req, &res); err != nil {
 		logger.WithError(err).Warn("Failed to query latest events")
-		return nil, &e, nil
+		return nil, err
 	}
 	latestEvents := make([]string, len(res.LatestEvents))
 	for i := range res.LatestEvents {
@@ -771,7 +754,7 @@ func (t *txnReq) getMissingEvents(ctx context.Context, e gomatrixserverlib.Event
 			"%s pushed us an event but %d server(s) couldn't give us details about prev_events via /get_missing_events - dropping this event until it can",
 			t.Origin, len(servers),
 		)
-		return nil, nil, missingPrevEventsError{
+		return nil, missingPrevEventsError{
 			eventID: e.EventID(),
 			err:     err,
 		}
@@ -809,14 +792,14 @@ Event:
 			"%s pushed us an event but couldn't give us details about prev_events via /get_missing_events - dropping this event until it can",
 			t.Origin,
 		)
-		return nil, nil, missingPrevEventsError{
+		return nil, missingPrevEventsError{
 			eventID: e.EventID(),
 			err:     err,
 		}
 	}
 
 	// we processed everything!
-	return newEvents, nil, nil
+	return newEvents, nil
 }
 
 func (t *txnReq) lookupMissingStateViaState(ctx context.Context, roomID, eventID string, roomVersion gomatrixserverlib.RoomVersion) (

federationapi/routing/send_test.go

@@ -516,6 +516,23 @@ func TestTransactionFetchMissingPrevEvents(t *testing.T) {
 
 	var rsAPI *testRoomserverAPI // ref here so we can refer to inputRoomEvents inside these functions
 	rsAPI = &testRoomserverAPI{
+		queryEventsByID: func(req *api.QueryEventsByIDRequest) api.QueryEventsByIDResponse {
+			res := api.QueryEventsByIDResponse{}
+			for _, ev := range testEvents {
+				for _, id := range req.EventIDs {
+					if ev.EventID() == id {
+						res.Events = append(res.Events, ev)
+					}
+				}
+			}
+			return res
+		},
+		queryStateAfterEvents: func(req *api.QueryStateAfterEventsRequest) api.QueryStateAfterEventsResponse {
+			return api.QueryStateAfterEventsResponse{
+				PrevEventsExist: true,
+				StateEvents:     testEvents[:5],
+			}
+		},
 		queryMissingAuthPrevEvents: func(req *api.QueryMissingAuthPrevEventsRequest) api.QueryMissingAuthPrevEventsResponse {
 			missingPrevEvent := []string{"missing_prev_event"}
 			if len(req.PrevEventIDs) == 1 {