# File lib/rspec/mocks/message_expectation.rb, line 160
      def and_yield(*args, &block)
        yield @eval_context = Object.new.extend(RSpec::Mocks::InstanceExec) if block
        @args_to_yield << args
        self.initial_implementation_action = AndYieldImplementation.new(@args_to_yield, @eval_context, @error_generator)
        self
      end