Fix newly found linter issues (#3099)

Fixes the issues found in
https://github.com/matrix-org/dendrite/actions/runs/5155539352/jobs/9285342056#step:5:22.
Only naked returns in longer functions.

roomserver/internal/perform/perform_peek.go

@@ -157,7 +157,7 @@ func (r *Peeker) performPeekRoomByID(
 		content := map[string]string{}
 		if err = json.Unmarshal(ev.Content(), &content); err != nil {
 			util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for history visibility failed")
-			return
+			return "", err
 		}
 		if visibility, ok := content["history_visibility"]; ok {
 			worldReadable = visibility == "world_readable"
@@ -185,7 +185,7 @@ func (r *Peeker) performPeekRoomByID(
 		},
 	})
 	if err != nil {
-		return
+		return "", err
 	}
 
 	// By this point, if req.RoomIDOrAlias contained an alias, then

syncapi/routing/messages.go

@@ -314,11 +314,12 @@ func (r *messagesReq) retrieveEvents() (
 	clientEvents []synctypes.ClientEvent, start,
 	end types.TopologyToken, err error,
 ) {
+	emptyToken := types.TopologyToken{}
 	// Retrieve the events from the local database.
 	streamEvents, err := r.snapshot.GetEventsInTopologicalRange(r.ctx, r.from, r.to, r.roomID, r.filter, r.backwardOrdering)
 	if err != nil {
 		err = fmt.Errorf("GetEventsInRange: %w", err)
-		return
+		return []synctypes.ClientEvent{}, emptyToken, emptyToken, err
 	}
 
 	var events []*rstypes.HeaderedEvent
@@ -333,11 +334,11 @@ func (r *messagesReq) retrieveEvents() (
 	// on the ordering), or we've reached a backward extremity.
 	if len(streamEvents) == 0 {
 		if events, err = r.handleEmptyEventsSlice(); err != nil {
-			return
+			return []synctypes.ClientEvent{}, emptyToken, emptyToken, err
 		}
 	} else {
 		if events, err = r.handleNonEmptyEventsSlice(streamEvents); err != nil {
-			return
+			return []synctypes.ClientEvent{}, emptyToken, emptyToken, err
 		}
 	}
 

syncapi/streams/stream_pdu.go

@@ -489,7 +489,7 @@ func (p *PDUStreamProvider) getJoinResponseForCompleteSync(
 
 	stateEvents, err := snapshot.CurrentState(ctx, roomID, stateFilter, excludingEventIDs)
 	if err != nil {
-		return
+		return jr, err
 	}
 
 	jr.Summary, err = snapshot.GetRoomSummary(ctx, roomID, device.UserID)
@@ -542,7 +542,7 @@ func (p *PDUStreamProvider) getJoinResponseForCompleteSync(
 		}
 		backwardTopologyPos, backwardStreamPos, err = snapshot.PositionInTopology(ctx, event.EventID())
 		if err != nil {
-			return
+			return jr, err
 		}
 		prevBatch = &types.TopologyToken{
 			Depth:       backwardTopologyPos,

userapi/storage/shared/storage.go

@@ -644,7 +644,7 @@ func (d *Database) CreateDevice(
 		for i := 1; i <= 5; i++ {
 			newDeviceID, returnErr = generateDeviceID()
 			if returnErr != nil {
-				return
+				return nil, returnErr
 			}
 
 			returnErr = d.Writer.Do(d.DB, nil, func(txn *sql.Tx) error {
@@ -653,7 +653,7 @@ func (d *Database) CreateDevice(
 				return err
 			})
 			if returnErr == nil {
-				return
+				return dev, nil
 			}
 		}
 	}