public void accept_visitor()
        {
            var executor = MockRepository.GenerateMock<IStepExecutor>();

            var step = new InvalidGrammarStep(new StepValues("foo"), "grammar is wonky");

            step.AcceptVisitor(executor);

            executor.AssertWasCalled(x => x.Line(step));
        }
        public void accept_visitor()
        {
            var executor = Substitute.For<ILineStepGatherer>();

            var step = new InvalidGrammarStep(new StepValues("foo"), "grammar is wonky");

            step.AcceptVisitor(executor);

            executor.Received().Line(step);
        }