Add gosimple linter (#242)

linter.json

@@ -16,6 +16,7 @@
         "misspell",
         "unparam",
         "errcheck",
-        "vet"
+        "vet",
+        "gosimple"
     ]
 }

src/github.com/matrix-org/dendrite/clientapi/auth/storage/devices/storage.go

@@ -67,10 +67,7 @@ func (d *Database) CreateDevice(
 		}
 
 		dev, err = d.devices.insertDevice(ctx, txn, deviceID, localpart, accessToken)
-		if err != nil {
-			return err
-		}
-		return nil
+		return err
 	})
 	return
 }

src/github.com/matrix-org/dendrite/clientapi/producers/syncapi.go

@@ -45,9 +45,6 @@ func (p *SyncAPIProducer) SendData(userID string, roomID string, dataType string
 	m.Key = sarama.StringEncoder(userID)
 	m.Value = sarama.ByteEncoder(value)
 
-	if _, _, err := p.Producer.SendMessage(&m); err != nil {
-		return err
-	}
-
-	return nil
+	_, _, err = p.Producer.SendMessage(&m)
+	return err
 }

src/github.com/matrix-org/dendrite/clientapi/producers/userupdate.go

@@ -57,9 +57,6 @@ func (p *UserUpdateProducer) SendUpdate(
 	}
 	m.Value = sarama.ByteEncoder(value)
 
-	if _, _, err := p.Producer.SendMessage(&m); err != nil {
-		return err
-	}
-
-	return nil
+	_, _, err = p.Producer.SendMessage(&m)
+	return err
 }

src/github.com/matrix-org/dendrite/common/keydb/server_key_table.go

@@ -116,10 +116,7 @@ func (s *serverKeyStatements) upsertServerKeys(
 		string(request.ServerName), string(request.KeyID), nameAndKeyID(request),
 		int64(keys.ValidUntilTS), keyJSON,
 	)
-	if err != nil {
-		return err
-	}
-	return nil
+	return err
 }
 
 func nameAndKeyID(request gomatrixserverlib.PublicKeyRequest) string {

src/github.com/matrix-org/dendrite/common/test/config.go

@@ -135,17 +135,14 @@ func NewMatrixKey(matrixKeyPath string) (err error) {
 		err = keyOut.Close()
 	})()
 
-	if err = pem.Encode(keyOut, &pem.Block{
+	err = pem.Encode(keyOut, &pem.Block{
 		Type: "MATRIX PRIVATE KEY",
 		Headers: map[string]string{
 			"Key-ID": "ed25519:" + base64.RawStdEncoding.EncodeToString(data[:3]),
 		},
 		Bytes: data[3:],
-	}); err != nil {
-		return err
-	}
-
-	return nil
+	})
+	return err
 }
 
 const certificateDuration = time.Hour * 24 * 365 * 10
@@ -191,12 +188,9 @@ func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
 		return err
 	}
 	defer keyOut.Close() // nolint: errcheck
-	if err = pem.Encode(keyOut, &pem.Block{
+	err = pem.Encode(keyOut, &pem.Block{
 		Type:  "RSA PRIVATE KEY",
 		Bytes: x509.MarshalPKCS1PrivateKey(priv),
-	}); err != nil {
-		return err
-	}
-
-	return nil
+	})
+	return err
 }

src/github.com/matrix-org/dendrite/federationapi/writers/threepid.go

@@ -347,9 +347,5 @@ func fillDisplayName(
 	// Use the m.room.third_party_invite event to fill the "displayname" and
 	// update the m.room.member event's content with it
 	content.ThirdPartyInvite.DisplayName = thirdPartyInviteContent.DisplayName
-	if err := builder.SetContent(content); err != nil {
-		return err
-	}
-
-	return nil
+	return builder.SetContent(content)
 }

src/github.com/matrix-org/dendrite/mediaapi/fileutils/fileutils.go

@@ -55,7 +55,7 @@ func GetPathFromBase64Hash(base64Hash types.Base64Hash, absBasePath config.Path)
 	// check if the absolute absBasePath is a prefix of the absolute filePath
 	// if so, no directory escape has occurred and the filePath is valid
 	// Note: absBasePath is already absolute
-	if strings.HasPrefix(filePath, string(absBasePath)) == false {
+	if !strings.HasPrefix(filePath, string(absBasePath)) {
 		return "", fmt.Errorf("Invalid filePath (not within absBasePath %v): %v", absBasePath, filePath)
 	}
 

src/github.com/matrix-org/dendrite/mediaapi/thumbnailer/thumbnailer.go

@@ -80,11 +80,7 @@ func SelectThumbnail(desired types.ThumbnailSize, thumbnails []*types.ThumbnailM
 		fitness := calcThumbnailFitness(types.ThumbnailSize(thumbnailSize), nil, desired)
 		if isBetter := fitness.betterThan(bestFit, desired.ResizeMethod == "crop"); isBetter {
 			bestFit = fitness
-			chosenThumbnailSize = &types.ThumbnailSize{
-				Width:        thumbnailSize.Width,
-				Height:       thumbnailSize.Height,
-				ResizeMethod: thumbnailSize.ResizeMethod,
-			}
+			chosenThumbnailSize = (*types.ThumbnailSize)(&thumbnailSize)
 		}
 	}
 

src/github.com/matrix-org/dendrite/mediaapi/thumbnailer/thumbnailer_nfnt.go

@@ -156,7 +156,7 @@ func createThumbnail(src types.Path, img image.Image, config types.ThumbnailSize
 	logger.WithFields(log.Fields{
 		"ActualWidth":  width,
 		"ActualHeight": height,
-		"processTime":  time.Now().Sub(start),
+		"processTime":  time.Since(start),
 	}).Info("Generated thumbnail")
 
 	stat, err := os.Stat(string(dst))

src/github.com/matrix-org/dendrite/mediaapi/writers/download.go

@@ -155,7 +155,7 @@ func (r *downloadRequest) jsonErrorResponse(w http.ResponseWriter, res util.JSON
 
 // Validate validates the downloadRequest fields
 func (r *downloadRequest) Validate() *util.JSONResponse {
-	if mediaIDRegex.MatchString(string(r.MediaMetadata.MediaID)) == false {
+	if !mediaIDRegex.MatchString(string(r.MediaMetadata.MediaID)) {
 		return &util.JSONResponse{
 			Code: 404,
 			JSON: jsonerror.NotFound(fmt.Sprintf("mediaId must be a non-empty string using only characters in %v", mediaIDCharacters)),
@@ -337,7 +337,7 @@ func (r *downloadRequest) getThumbnailFile(
 		thumbnail, thumbnailSize = thumbnailer.SelectThumbnail(r.ThumbnailSize, thumbnails, thumbnailSizes)
 		// If dynamicThumbnails is true and we are not over-loaded then we would have generated what was requested above.
 		// So we don't try to generate a pre-generated thumbnail here.
-		if thumbnailSize != nil && dynamicThumbnails == false {
+		if thumbnailSize != nil && !dynamicThumbnails {
 			r.Logger.WithFields(log.Fields{
 				"Width":        thumbnailSize.Width,
 				"Height":       thumbnailSize.Height,
@@ -525,7 +525,7 @@ func (r *downloadRequest) fetchRemoteFileAndStoreMetadata(
 		// If the file is a duplicate (has the same hash as an existing file) then
 		// there is valid metadata in the database for that file. As such we only
 		// remove the file if it is not a duplicate.
-		if duplicate == false {
+		if !duplicate {
 			finalDir := filepath.Dir(string(finalPath))
 			fileutils.RemoveDir(types.Path(finalDir), r.Logger)
 		}

src/github.com/matrix-org/dendrite/mediaapi/writers/upload.go

@@ -226,7 +226,7 @@ func (r *uploadRequest) storeFileAndMetadata(tmpDir types.Path, absBasePath conf
 		// If the file is a duplicate (has the same hash as an existing file) then
 		// there is valid metadata in the database for that file. As such we only
 		// remove the file if it is not a duplicate.
-		if duplicate == false {
+		if !duplicate {
 			fileutils.RemoveDir(types.Path(path.Dir(string(finalPath))), r.Logger)
 		}
 		return &util.JSONResponse{

src/github.com/matrix-org/dendrite/publicroomsapi/directory/public_rooms.go

@@ -102,10 +102,7 @@ func fillPublicRoomsReq(httpReq *http.Request, request *publicRoomReq) *util.JSO
 		request.Since = httpReq.FormValue("since")
 		return nil
 	} else if httpReq.Method == "POST" {
-		if reqErr := httputil.UnmarshalJSONRequest(httpReq, request); reqErr != nil {
-			return reqErr
-		}
-		return nil
+		return httputil.UnmarshalJSONRequest(httpReq, request)
 	}
 
 	return &util.JSONResponse{

src/github.com/matrix-org/dendrite/roomserver/alias/alias.go

@@ -217,11 +217,7 @@ func (r *RoomserverAliasAPI) sendUpdatedAliasesEvent(
 	var inputRes api.InputRoomEventsResponse
 
 	// Send the request
-	if err := r.InputAPI.InputRoomEvents(ctx, &inputReq, &inputRes); err != nil {
-		return err
-	}
-
-	return nil
+	return r.InputAPI.InputRoomEvents(ctx, &inputReq, &inputRes)
 }
 
 // SetupHTTP adds the RoomserverAliasAPI handlers to the http.ServeMux.

src/github.com/matrix-org/dendrite/roomserver/input/latest_events.go

@@ -102,8 +102,7 @@ type latestEventsUpdater struct {
 }
 
 func (u *latestEventsUpdater) doUpdateLatestEvents() error {
-	var prevEvents []gomatrixserverlib.EventReference
-	prevEvents = u.event.PrevEvents()
+	prevEvents := u.event.PrevEvents()
 	oldLatest := u.updater.LatestEvents()
 	u.lastEventIDSent = u.updater.LastEventIDSent()
 	u.oldStateNID = u.updater.CurrentStateSnapshotNID()
@@ -194,10 +193,7 @@ func (u *latestEventsUpdater) latestState() error {
 	u.stateBeforeEventRemoves, u.stateBeforeEventAdds, err = state.DifferenceBetweeenStateSnapshots(
 		u.ctx, u.db, u.newStateNID, u.stateAtEvent.BeforeStateSnapshotNID,
 	)
-	if err != nil {
-		return err
-	}
-	return nil
+	return err
 }
 
 func calculateLatest(
@@ -211,7 +207,7 @@ func calculateLatest(
 	for _, l := range oldLatest {
 		keep := true
 		for _, prevEvent := range prevEvents {
-			if l.EventID == prevEvent.EventID && bytes.Compare(l.EventSHA256, prevEvent.EventSHA256) == 0 {
+			if l.EventID == prevEvent.EventID && bytes.Equal(l.EventSHA256, prevEvent.EventSHA256) {
 				// This event can be removed from the latest events cause we've found an event that references it.
 				// (If an event is referenced by another event then it can't be one of the latest events in the room
 				//  because we have an event that comes after it)

src/github.com/matrix-org/dendrite/syncapi/storage/syncserver.go

@@ -461,9 +461,7 @@ func (d *SyncServerDatabase) fetchMissingStateEvents(
 	if len(stateEvents) != len(missing) {
 		return nil, fmt.Errorf("failed to map all event IDs to events: (got %d, wanted %d)", len(stateEvents), len(missing))
 	}
-	for _, e := range stateEvents {
-		events = append(events, e)
-	}
+	events = append(events, stateEvents...)
 	return events, nil
 }