ClassMethodsHelper.rb

module ClassMethods
  def my_context(description, options = {}, &block)
    context(description) do
      before(:each) do
        puts "omg!"
      end

      after(:each) do
        puts "win!"
      end

      yield
    end
  end
end

RSpec.configure { |config| config.extend(ClassMethods) }

RSpecTest.rb

describe Foo do
  my_context('something special') do
    it "always wins" do
      subject.should be_win
    end
  end
end

ThisWorks.rb

module ClassMethods
  def my_context(description, options = {}, &block)
    context(description) do
      before(:each) do
        puts "omg!"
      end

      after(:each) do
        puts "win!"
      end
    end.context(&block)
  end
end

RSpec.configure { |config| config.extend(ClassMethods) }

zzzOtherHelper.rb

# Whereas.. this one seems to work correctly (not yielding).

module ClassMethods
  def my_context(description, options = {}, &block)
    context(description) do
      before(:each) do
        puts "omg!"
      end

      after(:each) do
        puts "win!"
      end

      it "always wins" do
        subject.should be_win
      end
    end
  end
end

RSpec.configure { |config| config.extend(ClassMethods) }