got := make([]byte, len(v.want))
		f.formatNumeric(got, v.in)
		ok := (f.err == nil)
		if ok != v.ok {
			if v.ok {
				t.Errorf("formatNumeric(%d): got formatting failure, want success", v.in)
			} else {
				t.Errorf("formatNumeric(%d): got formatting success, want failure", v.in)
			}
		}
		if string(got) != v.want {
			t.Errorf("formatNumeric(%d): got %q, want %q", v.in, got, v.want)
		}
	}
}

func (*parser) parseString(b []byte) string {
	if i := bytes.IndexByte(b, 0); i >= 0 {
		return string(b[:i])
	}
	return string(b)
}

// formatString copies s into b, NUL-terminating if possible.
func (f *formatter) formatString(b []byte, s string) {
	if len(s) > len(b) {
		f.err = ErrFieldTooLong
	}
	copy(b, s)
	if len(s) < len(b) {
		b[len(s)] = 0
	}

		// Preserving the compression metadata.
		compressMetadata[ReservedMetadataPrefix+"compression"] = compressionAlgorithmV2
		compressMetadata[ReservedMetadataPrefix+"actual-size"] = strconv.FormatInt(actualSize, 10)

		reader = etag.NewReader(ctx, reader, nil, nil)
		wantEncryption := crypto.Requested(r.Header)
		s2c, cb := newS2CompressReader(reader, actualSize, wantEncryption)
		dstOpts.IndexCB = cb

		if v := opts.UserDefined[ReservedMetadataPrefix+"Actual-Object-Size"]; v != "" {
			fi.Metadata[ReservedMetadataPrefix+"actual-size"] = v
		}
	} else {
		fi.Metadata[ReservedMetadataPrefix+"actual-size"] = strconv.FormatInt(objectActualSize, 10)
	}

	if opts.DataMovement {
		fi.SetDataMov()
	}

	// Update all erasure metadata, make sure to not modify fields like
	// checksum which are different on each disks.

	tags["set"] = strconv.Itoa(er.setIndex)
	tags["pool"] = strconv.Itoa(er.poolIndex)
	tags["merrs"] = joinErrs(errs)
	tags["derrs"] = fmt.Sprintf("%v", dataErrsByPart)
	if m.IsValid() {
		tags["sz"] = strconv.FormatInt(m.Size, 10)
		tags["mt"] = m.ModTime.Format(iso8601Format)
		tags["d:p"] = fmt.Sprintf("%d:%d", m.Erasure.DataBlocks, m.Erasure.ParityBlocks)
	} else {
		tags["invalid"] = "1"