Create .dmg disk image from folder(s) in a smart way

dmgFromFolders.rb

#!/usr/bin/env ruby -wU
# juanfc 2024-03-16
# https://gist.github.com/juanfal/39206b7d47a1eacac35cbd1b98f6f5d3

if ARGV.length < 1 or (ARGV.length == 1 and ARGV[0] == '-h') then
    puts "Usage:
#$0 [destdmg] sourceFolder [sourceFolders..]
"
    exit 0
end

if ARGV.length == 1 then
    folders = ARGV
    thedmg = ARGV[0]
else
    if File.directory?(ARGV[0]) then
        folders = ARGV
    else
        folders = ARGV[1..]
    end
    thedmg = ARGV[0]
end

if not thedmg.end_with? ".dmg"
    thedmg = thedmg.gsub(/\/+$/, '') + ".dmg"
end

if (File.exist?(thedmg)) then
    $stderr.puts "File '#{thedmg}' already exists! Not touched"
    exit 1
end

folders.each{ |f|
    if not File.exist?(f) then
        $stderr.puts "Folder '#{f}' doesn't exists!"
        exit 1
    end
}

folders = "-srcfolder " + folders.map{|i| "'#{i}'"}.join(" -srcfolder ")

puts("hdiutil create '#{thedmg}' #{folders}")
system("hdiutil create '#{thedmg}' #{folders}")