Code cleanup and missing error checks

internal/backends/deezer/client.go

@@ -79,7 +79,10 @@ func listRequest[T Result](c Client, path string, offset int, limit int) (result
 			"limit": strconv.Itoa(limit),
 		}).
 		SetResult(&result)
-	c.setToken(request)
+	err = c.setToken(request)
+	if err != nil {
+		return
+	}
 	response, err := request.Get(path)
 
 	if response.StatusCode() != 200 {

internal/backends/scrobblerlog/parser.go

@@ -105,7 +105,7 @@ func Write(data io.Writer, listens models.ListensList) (lastTimestamp time.Time,
 		if !ok || rating == "" {
 			rating = "L"
 		}
-		tsvWriter.Write([]string{
+		err = tsvWriter.Write([]string{
 			listen.ArtistName(),
 			listen.ReleaseName,
 			listen.TrackName,

internal/backends/scrobblerlog/parser_test.go

@@ -103,7 +103,7 @@ func TestWrite(t *testing.T) {
 	require.NoError(t, err)
 	lastTimestamp, err := scrobblerlog.Write(buffer, log.Listens)
 	require.NoError(t, err)
-	result := string(buffer.Bytes())
+	result := buffer.String()
 	lines := strings.Split(result, "\n")
 	assert.Equal(5, len(lines))
 	assert.Equal("#AUDIOSCROBBLER/1.1", lines[0])

internal/backends/scrobblerlog/scrobblerlog.go

@@ -91,18 +91,18 @@ func (b *ScrobblerLogBackend) StartImport() error {
 		} else {
 			// Verify existing file is a scrobbler log
 			reader := bufio.NewReader(file)
-			err = ReadHeader(reader, &b.log)
-			if err != nil {
+			if err = ReadHeader(reader, &b.log); err != nil {
 				file.Close()
 				return err
 			}
-			file.Seek(0, 2)
+			if _, err = file.Seek(0, 2); err != nil {
+				return err
+			}
 		}
 	}
 
 	if !b.append {
-		err = WriteHeader(file, &b.log)
-		if err != nil {
+		if err = WriteHeader(file, &b.log); err != nil {
 			file.Close()
 			return err
 		}