leading zeros to in seqkit split/split2 output files

[uguyet]

This isn't a bug, but more of a suggestion:

The leading zeros in the output files generated by the seqkit split/split2 command should be more than 2 if there are more than 999 splits, to ensure that the files can be sorted easily.

Thanks in advance !

[shenwei356]

Good suggestion, a new option is added for split and split2:

  -W, --part-width int            number of digits used for output file part numbering (zero-padded),
                                  e.g., 001, 002 (default 3)

# if there are more than 1000 parts, increase the -W/--part-width
$ seqkit split2 hairpin.fa.gz -s 10000 -W 5
[INFO] split into 10000 seqs per file
[INFO] write 10000 sequences to file: hairpin.fa.gz.split/hairpin.part_00001.fa.gz
[INFO] write 10000 sequences to file: hairpin.fa.gz.split/hairpin.part_00002.fa.gz
[INFO] write 8645 sequences to file: hairpin.fa.gz.split/hairpin.part_00003.fa.gz

Thanks!