测试时在特定状态下启动状态机

Question

我正在尝试为我的状态机创建单元测试，以检查每个状态是否做了它应该做的事情。

我可以通过发布启动状态机的事件并创建达到所需状态所需的所有变量，使状态机进入任何状态。

简化的状态机：

 public class CheckFilesStateMachine : MassTransitStateMachine<DataState>, ICheckFilesStateMachine
    {
        #region Events
        public Event<IEventCheckFile> CheckFile { get; private set; }
        #endregion

        #region States
        
        public State CheckingForFiles { get; }

        public State ValidatingFiles { get; }

        public State NoFilesFound { get; }

        public State Validated { get; }

        public State FilesProcessed { get; }

        public State ValidationFailed{ get; }

        #endregion

        public DataStateMachine(IDataService dataService)
        {
            InstanceState(x => x.CurrentState);

            Event(() => CheckFile, x => x.CorrelateById(context => context.Message.Id));

            Initially(When(CheckFile).TransitionTo(CheckingForFiles));

            WhenEnter(CheckingForFiles, binder => binder
                .Then(x => x.Instance.Files= dataService.GetFiles())
                .IfElse(x => dataService.HasFiles(),
                        x => x.TransitionTo(ValidatingFiles),
                        x => x.TransitionTo(NoFilesFound))
                .Catch<Exception>(ex => ex
                    .Then(x => Console.WriteLine(x.Exception.Message))));

            WhenEnter(ValidatingFiles, binder => binder
                .IfElse(x => dataService.ValidateFiles(),
                        x => x.TransitionTo(Validated),
                        x => x.TransitionTo(ValidationFailed))
                .Catch<Exception>(ex => ex
                    .Then(x => Console.WriteLine(x.Exception.Message))));

            WhenEnter(NoFilesFound, binder => binder.Then(x => Console.WriteLine("No Files found")).Finalize());
            WhenEnter(Validated, binder => binder.Then(x => Console.WriteLine("Validated")).Finalize());
            WhenEnter(ValidationFailed, binder => binder.Then(x => Console.WriteLine("Validation Failed")).Finalize());

            SetCompletedWhenFinalized();
        }
    }

我编写了一些单元测试，我可以启动机器（遵循 MassTransit 文档中的 this 指南），但我想检查状态 CheckingForFiles 和 ValidatingFiles 是否正在独立执行它们应该执行的操作其他。

到目前为止，我可以通过遵循状态机的流程来模拟 IDataService 方法来达到所需的状态，但是有没有办法启动状态机并跳转到特定状态？

更新

假设我还有另一种状态：

 public class CheckFilesStateMachine : MassTransitStateMachine<DataState>, ICheckFilesStateMachine
    {
        #region Events
        public Event<IEventCheckFile> CheckFile { get; private set; }
        #endregion

        #region States
        
        public State CheckingForFiles { get; }

        public State ValidatingFiles { get; }

        public State DeletingFiles{ get; }

        public State NoFilesFound { get; }

        public State Validated { get; }

        public State FilesProcessed { get; }

        public State ValidationFailed{ get; }

        #endregion

        public DataStateMachine(IDataService dataService)
        {
            InstanceState(x => x.CurrentState);

            Event(() => CheckFile, x => x.CorrelateById(context => context.Message.Id));

            Initially(When(CheckFile).TransitionTo(CheckingForFiles));

            WhenEnter(CheckingForFiles, binder => binder
                .Then(x => x.Instance.Files= dataService.GetFiles())
                .IfElse(x => dataService.HasFiles(),
                        x => x.TransitionTo(ValidatingFiles),
                        x => x.TransitionTo(NoFilesFound))
                .Catch<Exception>(ex => ex
                    .Then(x => Console.WriteLine(x.Exception.Message))));

            WhenEnter(ValidatingFiles, binder => binder
                .IfElse(x => dataService.ValidateFiles(),
                        x => x.TransitionTo(Validated),
                        x => x.TransitionTo(DeletingFiles))
                .Catch<Exception>(ex => ex
                    .Then(x => Console.WriteLine(x.Exception.Message))));

            WhenEnter(DeletingFiles, binder => binder
                .Then(x => x.Instance.Files= dataService.RemoveFiles())
                .TransitionTo(ValidationFailed)
                .Catch<Exception>(ex => ex
                    .Then(x => Console.WriteLine(x.Exception.Message))));

            WhenEnter(NoFilesFound, binder => binder.Then(x => Console.WriteLine("No Files found")).Finalize());
            WhenEnter(Validated, binder => binder.Then(x => Console.WriteLine("Validated")).Finalize());
            WhenEnter(ValidationFailed, binder => binder.Then(x => Console.WriteLine("Validation Failed")).Finalize());

            SetCompletedWhenFinalized();
        }
    }

这种情况，我可以输入CheckingForFiles然后跳转到DeletingFiles吗？可以吗？

Answer 1

如果您使用基于容器的内存测试工具，您可以从容器中解析 saga 字典并添加一个实例：

var dictionary = provider.GetRequiredService<IndexedSagaDictionary<DataState>>();

dictionary.Add(new SagaInstance<DataState>(new DataState() 
{
    CorrelationId = dataId,
    CurrentState = "CheckingForFiles" 
}));

更新

最新版本的MassTransit，在使用测试工具时，有一个扩展方法来添加saga实例：

harness.AddSagaInstance<DataState>(dataId, x => 
{
    x.CurrentState = "CheckingForFiles";
});