gistfile1.rb

require 'test/unit'
require 'shoulda'

class Test::Unit::TestCase
  def self.context_helper(helper_arg, &block)
    context "context helper #{helper_arg}" do
      setup do
        @helper_arg = helper_arg
      end
      merge_block(&block) if block_given?
    end
  end
end

class SpecificTestCase < Test::Unit::TestCase
  context "An outter context" do
    setup do
      # @setup_var defined in a block which is called
      # when the test is run, inside a test instance scope.
      @setup_var = "not available in class scope"
    end

    # @setup_var is defined here as an argument to the
    # class method context_helper, in the class scope.
    # This is a different variable from the @setup_var
    # defined in the setup block.  At this point the
    # setup block has yet to be executed, so the
    # variable in the setup block has not been defined.
    context_helper(@setup_var) do
      should "be false" do
        assert_not_equal @setup_var, @helper_arg
      end

      should "be nil" do
        assert @helper_arg.nil?
      end
    end
  end
end