module RSpec::Core::Subject::ExampleMethods

def _attribute_chain(attribute)
  attribute.to_s.split('.')
end

def _nested_attribute(subject, attribute)
  _attribute_chain(attribute).inject(subject) do |inner_subject, attr|
    inner_subject.send(attr)
  end
end

def should(matcher=nil, message=nil)
  RSpec::Expectations::PositiveExpectationHandler.handle_matcher(subject, matcher, message)
end

def should_not(matcher=nil, message=nil)
  RSpec::Expectations::NegativeExpectationHandler.handle_matcher(subject, matcher, message)
end

def subject
  if defined?(@original_subject)
    @original_subject
  else
    @original_subject = instance_eval(&self.class.subject)
  end
end