Unable to attach test reporter... (newbie question)

Greetings!

Disclaimer: I'm extremely new to Ruby, and I'm getting very frustrated w/ this issue.

I'm trying to use Ruby 1.9.3 and do some basic unit tests. I have spent nearly a day trying to figure this out, and have got close, but come up dry. I've boiled this down to about the simplest I can (I hope).

I have the following Project structure, in ~/Dev/RubyTest193/
app/my_object.rb
test/myobject_test.rb
test/test-helper.rb
Gemfile

the contents are such:

app/my_object.rb

class MyObject
   def initialize( a_value )
      @my_value = a_value
   end
   attr_accessor :my_value
end

test/myobject_test.rb

require "test/unit"
require "./app/my_object"

class MyObjectTest < Test::Unit::TestCase
   def test_can_create_myobject
      me = MyObject.new( 42 )

      assert_not_nil( me )
   end
   def test_fail
      fail("Test to show failure")
   end
end

require 'minitest/reporters'
MiniTest::Unit.runner = MiniTest::SuiteRunner.new
if ENV["RM_INFO"] || ENV["TEAMCITY_VERSION"]
   MiniTest::Unit.runner.reporters << MiniTest::Reporters::RubyMineReporter.new
elsif ENV['TM_PID']
   MiniTest::Unit.runner.reporters << MiniTest::Reporters::RubyMateReporter.new
else
   MiniTest::Unit.runner.reporters << MiniTest::Reporters::ProgressReporter.new
end