RevBlob a = d.blob("a");
TemporaryBuffer.Heap pack = new TemporaryBuffer.Heap(1024);
packHeader(pack, 1);
pack.write((Constants.OBJ_REF_DELTA) << 4 | 4);
a.copyRawTo(pack);
deflate(pack, new byte[] { 0x1, 0x1, 0x1, 'b' });
digest(pack);
PackParser p = index(new UnionInputStream(
new ByteArrayInputStream(pack.toByteArray()),