fix: retain the batch.Close error

store/v2/commitment/metadata.go

@@ -59,36 +59,41 @@ func (m *MetadataStore) GetCommitInfo(version uint64) (*proof.CommitInfo, error)
 	return cInfo, nil
 }
 
-func (m *MetadataStore) flushCommitInfo(version uint64, cInfo *proof.CommitInfo) error {
+func (m *MetadataStore) flushCommitInfo(version uint64, cInfo *proof.CommitInfo) (err error) {
 	// do nothing if commit info is nil, as will be the case for an empty, initializing store
 	if cInfo == nil {
-		return nil
+		return
 	}
 
 	batch := m.kv.NewBatch()
-	defer batch.Close()
+	defer func() {
+		cErr := batch.Close()
+		if err == nil {
+			err = cErr
+		}
+	}()
 	cInfoKey := []byte(fmt.Sprintf(commitInfoKeyFmt, version))
 	value, err := cInfo.Marshal()
 	if err != nil {
-		return err
+		return
 	}
-	if err := batch.Set(cInfoKey, value); err != nil {
-		return err
+	if err = batch.Set(cInfoKey, value); err != nil {
+		return
 	}
 
 	var buf bytes.Buffer
 	buf.Grow(encoding.EncodeUvarintSize(version))
-	if err := encoding.EncodeUvarint(&buf, version); err != nil {
-		return err
+	if err = encoding.EncodeUvarint(&buf, version); err != nil {
+		return
 	}
-	if err := batch.Set([]byte(latestVersionKey), buf.Bytes()); err != nil {
-		return err
+	if err = batch.Set([]byte(latestVersionKey), buf.Bytes()); err != nil {
+		return
 	}
 
-	if err := batch.WriteSync(); err != nil {
-		return err
+	if err = batch.WriteSync(); err != nil {
+		return
 	}
-	return nil
+	return
 }
 
 func (m *MetadataStore) deleteCommitInfo(version uint64) error {