Execute unittests with rake in RadRails


I’m absolutly new to Ruby on Rails and try to set up my development
environment. I installed RadRails, created a project and generated my
first model and controller. Now I want to execute my unittests with
rake. I have the rudimental automatically created rakefile:

Add your own tasks in files placed in lib/tasks ending in .rake,

for example lib/tasks/capistrano.rake, and they will automatically be

available to Rake.

require(File.join(File.dirname(FILE), ‘config’, ‘boot’))

require ‘rake’
require ‘rake/testtask’
require ‘rake/rdoctask’

require ‘tasks/rails’

And I have a test in test/unit/testname_test.rb. I can execute this test
manually with right mouseklick on it (in RadRails) --> Execute as -->
Test::Unit Test. Now my - probably very simple to be answered -
question: How do I execute this test via rake? Please tell me EVERY
SINGLE STEP (every line of “code” and where I have to put it). Thank