JRuby Windows Match Error

# This class knows about supported JRubyArt operating systems
class HostOS
  def self.os
    detect_os = RbConfig::CONFIG['host_os']
    case detect_os
    when /mac|darwin/ then :mac
    when /gnueabihf/ then :arm 
    when /linux/ then :linux
    when /solaris|bsd/ then :unix
    else
      WIN_PATTERNS.find { |reg| reg.match?(detect_os) } # <- issue here
      raise "unsupported os: #{detect_os.inspect}" if Regexp.last_match.nil? # <- this will never be true
      :windows
    end
  end
end

# Solution I suppose
windows = WIN_PATTERNS.detect { |reg| reg.match?(detect_os) }
raise "unsupported os: #{detect_os.inspect}" unless windows
:windows