Extracting the latest version in a `0.0.0.0` formatted versioning scheme.

.gitconfig

# add the following under `[alias]`
    latest-tag = "!sh -c 'git tag | get_latest_version.rb' -"
    recent-tags = "!sh -c 'git tag | get_latest_version.rb -c ${1}' -"

get_latest_version.rb

#!/usr/bin/env ruby

args = $*.to_a

if args.index("-c")
  ct = [args[args.index("-c") + 1].to_i, 1].max
end

tags = $stdin.to_a

tags.collect! {|v| v = v.split('.')
    v.collect! {|i| i.to_i}
  }

tags.sort! {|a, b| a <=> b }

if ct
  ct = [ct, tags.length].min
  tag_range = tags[-ct..-1]
  
  puts "LAST #{ct} VERSIONS:"
  tag_range.each {|i| puts "#{i.join('.')}" }
else
  puts "LATEST VERSION: #{tags[-1].join('.')}"
end