for _, s := range spd {
				hdr.Size += s.Length
				spb = append(strconv.AppendInt(spb, s.Offset, 10), '\n')
				spb = append(strconv.AppendInt(spb, s.Length, 10), '\n')
			}
			pad := blockPadding(int64(len(spb)))
			spb = append(spb, zeroBlock[:pad]...)
			hdr.Size += int64(len(spb)) // Accounts for encoded sparse map

			// Add and modify appropriate PAX records.
			dir, file := path.Split(realName)

func alignSparseEntries(src []sparseEntry, size int64) []sparseEntry {
	dst := src[:0]
	for _, s := range src {
		pos, end := s.Offset, s.endOffset()
		pos += blockPadding(+pos) // Round-up to nearest blockSize
		if end != size {
			end -= blockPadding(-end) // Round-down to nearest blockSize
		}
		if pos < end {
			dst = append(dst, sparseEntry{Offset: pos, Length: end - pos})
		}
	}
	return dst
}

			t.Errorf("test %d, Header.Size = %d, want %d", i, hdr.Size, v.wantSize)
		}
	}
}

func TestReadGNUSparsePAXHeaders(t *testing.T) {
	padInput := func(s string) string {
		return s + string(zeroBlock[:blockPadding(int64(len(s)))])
	}

	vectors := []struct {
		inputData string
		inputHdrs map[string]string
		wantMap   sparseDatas
		wantSize  int64
		wantName  string
		wantErr   error
	}{{