Interesting use of respond_to here

good stuff on $stdout.... usually, when you re-assign stdout, you want to only do it temporarily, so you can do your thing, check your thing, and reset your thing.

Maybe use this technique on http://thinkingdigitally.com/archive/capturing-output-from-puts-in-ruby/

require 'stringio'

module Kernel

  def capture_stdout
    out = StringIO.new
    $stdout = out
    yield
    return out
  ensure
    $stdout = STDOUT
  end

end

results = capture_stdout do
  puts "hi!"
end

results.string
=> "hi!\n"

Only real tricky part is the "\n".... if you hate that, you could change to

results = capture_stdout do
  print "hi"
end
results.string
=> "hi"

You might want to use the "is near" when dealing with stuff like this.

clerk.tast_measurement.should be_within(0.01).of(4.44)