Compress::Gzip::Reader cannot open a file in BGZF format

[kojix2]

The BGZF format is a GZip format used in the bioinformatics area and uses extra fields.
Crystal's standard library Compress::Gzip::Reader cannot open it.

Crystal Forum:
https://forum.crystal-lang.org/t/compress-reader-cannot-open-a-file-in-bgzf-format-is-this-a-bug/6262/2

Steps to Reproduce

1. Install tabix:

   sudo apt install tabix

   dpkg -L tabix | grep bgzip
   # /usr/bin/bgzip
   # /usr/share/man/man1/bgzip.1.gz
   

2. Compress a file with bgzip:

   bgzip -k your.txt

3. Decompress and view the file:

   zcat your.txt.gz

4. Read compressed file in Crystal:

   require "compress/gzip"
   
   string = File.open("your.txt.gz") do |file|
     Compress::Gzip::Reader.open(file) do |gzip|
       gzip.gets_to_end
     end
   end

Unhandled exception: deflate: invalid stored block lengths (Compress::Deflate::Error)