# File lib/grit/git-ruby/internal/pack.rb, line 173
        def each_sha1
          with_idx do |idx|
            if @version == 2
              data = read_data_v2(idx)
              data.each do |sha1, crc, offset|
                yield sha1
              end
            else
              pos = SHA1Start
              @size.times do
                sha1 = idx[pos,SHA1Size]
                pos += EntrySize
                yield sha1
              end
            end
          end
        end