如何正确指示与步骤一起使用的 StepArgumentTransformation？

Question

我正在尝试在两个不同的步骤中将 SpecFlow 步骤参数转换为相同的返回类型。

这是简化的功能文件：

Feature: TransforMe

@UseTableToIntsTransform
Scenario: First
Given I have some condition
When I do something
Then the results should be
| Index |
| 1     |
| 2     |
| 3     |

@UseStringToIntsTransform
Scenario Outline: Second
Given I have some condition
When I do something
Then the results should contain <expectedResults>

Examples: 
| expectedResults |
| 0               |
| 0,3,5,7,10      |

我要做的是从 Then 步骤中的场景转换 Table 和 string 以将 IEnumerable 作为 step 参数返回。我正在尝试使用范围，属性正则表达式限制，......没有成功。以下是步骤定义：

[Binding]
public class TransforMeSteps
{
    [Given(@"I have some condition")]
    public void GivenIHaveSomeCondition()
    { }

    [When(@"I do something")]
    public void WhenIDoSomething()
    { }

    [Then(@"the results should be")]
    [Scope(Scenario = "First", Tag = "UseTableToIntsTransform")]
    public void ThenTheResultsShouldBe(IEnumerable<int> results)
    {
        results.ToList().ForEach(x => Debug.WriteLine(x));
    }

    [Then(@"the results should contain (.*)")]
    [Scope(Scenario = "Second", Tag = "UseStringToIntsTransform")]
    public void ThenTheResultsShouldContain(IEnumerable<int> results)
    {
        results.ToList().ForEach(x => Debug.WriteLine(x));
    }
}

[Binding]
[Scope(Scenario = "First", Tag = "UseTableToIntsTransform")]
public class TableToIntsTransform
{
    [StepArgumentTransformation(@"the results should be")]
    public IEnumerable<int> TableToInts(Table intsTable)
    {
        return new List<int> { 1, 2, 3 };
    }
}

[Binding]
public class StringToIntsTransform
{
    [StepArgumentTransformation(@"the results should contain (.*)")]
    [Scope(Scenario = "Second", Tag = "UseStringToIntsTransform")]
    public IEnumerable<int> StringToInts(string integersString)
    {
        return new List<int> { 4, 5, 6 };
    }
}

对于“第一个”场景，我得到了绿色测试，但有警告：多步转换与输入匹配（| 索引 | | 1 | | 2 | | 3 | ，目标类型：[System.Collections.Generic.IEnumerable`1[System.Int32]]）。我们使用第一个。

对于“第二个”场景，抛出 InvalidCastException：Invalid cast from 'System.String' to 'System.Collections.Generic.IEnumerable`1[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral , PublicKeyToken=b77a5c561934e089]]'。

每个转换都通过相应的步骤定义自行工作。例如，如果我将转换类的顺序更改为首先具有 StringToIntsTransform，那么“第二”场景的测试是绿色的。

那么我如何正确地指示或限制正确转换的范围？

我希望有这样的东西作为我的最终解决方案：

    [Then(@"the results should contain (.*)")]
    [Then(@"the results should be")]
    public void ThenTheResultsShouldContain(IEnumerable<int> results)
    {
        results.ToList().ForEach(x => Debug.WriteLine(x));
    }

所以只有一步定义。

Answer 1

这可能并不理想，但我要做的是创建一个类来表示我要返回的对象并在此处使用它。这个类可能只是简单地包装一个 int，但是作为一个不同的类将允许 specflow 区分要使用的步骤转换。所以大致如下：

[Binding]
public class TransforMeSteps
{
    [Given(@"I have some condition")]
    public void GivenIHaveSomeCondition()
    { }

    [When(@"I do something")]
    public void WhenIDoSomething()
    { }

    [Then(@"the results should be")]
    [Scope(Scenario = "First", Tag = "UseTableToIntsTransform")]
    public void ThenTheResultsShouldBe(IEnumerable<Index> results)
    {
        results.ToList().ForEach(x => Debug.WriteLine(x));
    }

    [Then(@"the results should contain (.*)")]
    [Scope(Scenario = "Second", Tag = "UseStringToIntsTransform")]
    public void ThenTheResultsShouldContain(IEnumerable<ExpectedResult> results)
    {
        results.ToList().ForEach(x => Debug.WriteLine(x));
    }
}

[Binding]
[Scope(Scenario = "First", Tag = "UseTableToIntsTransform")]
public class TableToIntsTransform
{
    [StepArgumentTransformation(@"the results should be")]
    public IEnumerable<Index> TableToInts(Table intsTable)
    {
        return new List<Index> { 1, 2, 3 };
    }
}

[Binding]
public class StringToIntsTransform
{
    [StepArgumentTransformation(@"the results should contain (.*)")]
    [Scope(Scenario = "Second", Tag = "UseStringToIntsTransform")]
    public IEnumerable<ExpectedResult> StringToInts(string integersString)
    {
        return new List<ExpectedResult> { 4, 5, 6 };
    }
}

public class Index
{
     private int value;
     public Index(int value)
     { this.value=value;}

     public static implicit operator int(Index index)
     {
         return index.value;
     }

     public static implicit operator Index(int value)
     {
         return new Index(value);
     }
}

您也许可以将 Index 和 ExpectedResult 类隐式转换为 int 以使其更方便使用。