=begin
Can the Test unit be used to test methods or variables in other files? I've
come across this reference, (http://clarkware.com/cgi/blosxom/2005/03/18),
which seems to test snipets of code within the test itself. The idea is to
test that the array x is not empty nd use the Test Unit to do it.
=end

# foo.rb
x = `df`.grep(/^\/dev/).sort # in order of dev name

# test_foo.rb
require 'test/unit'
require '/path/to/foo.rb'

# test that the df cmd exists on the system that we are running it on
# output of cmd is put in array. this array should NOT be !!--empty--!!

class TESTX < Test::Unit::TestCase
  def test_no_df
    assert(x.empty?, "df command not found")
  end
end

 - jjm