t.Errorf("test %d, validateSparseEntries() = %v, want %v", i, gotValid, v.wantValid)
		}
		if !v.wantValid {
			continue
		}
		gotAligned := alignSparseEntries(append([]sparseEntry{}, v.in...), v.size)
		if !slices.Equal(gotAligned, v.wantAligned) {
			t.Errorf("test %d, alignSparseEntries():\ngot  %v\nwant %v", i, gotAligned, v.wantAligned)
		}
		gotInverted := invertSparseEntries(append([]sparseEntry{}, v.in...), v.size)

			return false // Region extends beyond the actual size
		case pre.endOffset() > cur.Offset:
			return false // Regions cannot overlap and must be in order
		}
		pre = cur
	}
	return true
}

// alignSparseEntries mutates src and returns dst where each fragment's
// starting offset is aligned up to the nearest block edge, and each
// ending offset is aligned down to the nearest block edge.
//

	/*
		// Handle sparse files.
		var spd sparseDatas
		var spb []byte
		if len(hdr.SparseHoles) > 0 {
			sph := append([]sparseEntry{}, hdr.SparseHoles...) // Copy sparse map
			sph = alignSparseEntries(sph, hdr.Size)
			spd = invertSparseEntries(sph, hdr.Size)

			// Format the sparse map.
			hdr.Size = 0 // Replace with encoded size
			spb = append(strconv.AppendInt(spb, int64(len(spd)), 10), '\n')