我最近开始了一个新项目，并决定使用它随Nunit3附带的Specflow 2.1。

目前，该项目已经安装完毕，Visual studio中的测试运行程序正在正确执行，但是，当我尝试从NUnit3控制台运行程序运行相同的测试时，我得到了一个错误。

我使用的命令是nunit3-console.exe--labels=all--framework=net-4.5 blah.testing.specflow.dll

我用相同的程序集添加了两个本机Nunit测试，它们都执行得很好，这是一个失败的specflow测试

NUnit Console Runner 3.2.1
Copyright (C) 2016 Charlie Poole

Runtime Environment
   OS Version: Microsoft Windows NT 10.0.10586.0
  CLR Version: 4.0.30319.42000

Test Files
    Blah.Testing.Specflow.dll

=> Blah.Testing.Specflow.MyTest.TestOne
=> Blah.Testing.Specflow.MyTest.TestTwo
=> Blah.Testing.Specflow.MyTestFeature.AddTwoNumbers

Errors and Failures

1) TearDown Error : Blah.Testing.Specflow.MyTestFeature
System.ArgumentNullException : Value cannot be null.
Parameter name: instance
TearDown : System.NullReferenceException : Object reference not set to an instance of an object.
   at BoDi.ObjectContainer.RegisterInstanceAs(Object instance, Type interfaceType, String name, Boolean dispose)
   at TechTalk.SpecRun.SpecFlowPlugin.Runtime.SpecRunTestRunnerManager.CreateTestRunnerInstance() in c:\TeamCity\BuildAgent\work\245a3e4d646c0875\SpecFlowPlugins\TechTalk.SpecRun.SpecFlowPlugin.2-0-0\Runtime\SpecRunTestRunnerManager.cs:line 33
   at TechTalk.SpecFlow.TestRunnerManager.CreateTestRunner(Int32 threadId)
   at TechTalk.SpecFlow.TestRunnerManager.GetTestRunner(Int32 threadId)
   at TechTalk.SpecFlow.TestRunnerManager.GetTestRunner(Assembly testAssembly, Nullable`1 managedThreadId)
   at Blah.Testing.Specflow.MyTestFeature.FeatureSetup() in D:\Projects\Blah\src\Testing\Blah.Testing.Specflow\MyTest.feature.cs:line 0
--TearDown
   at Blah.Testing.Specflow.MyTestFeature.FeatureTearDown() in D:\Projects\Blah\src\Testing\Blah.Testing.Specflow\MyTest.feature.cs:line 0

2) Error : Blah.Testing.Specflow.MyTestFeature.AddTwoNumbers
OneTimeSetUp: System.ArgumentNullException : Value cannot be null.
Parameter name: instance

Run Settings
    RuntimeFramework: net-4.5
    WorkDirectory: D:\Projects\Blah\src\Testing\Blah.Testing.Specflow\bin\Dev
    ImageRuntimeVersion: 4.0.30319
    ImageTargetFrameworkName: .NETFramework,Version=v4.5.1
    ImageRequiresX86: False
    ImageRequiresDefaultAppDomainAssemblyResolver: False
    NumberOfTestWorkers: 8

Test Run Summary
  Overall result: Failed
  Test Count: 3, Passed: 2, Failed: 1, Inconclusive: 0, Skipped: 0
    Failed Tests - Failures: 0, Errors: 1, Invalid: 0
  Start time: 2016-05-16 00:52:52Z
    End time: 2016-05-16 00:52:53Z
    Duration: 0.380 seconds

Results (nunit3) saved as TestResult.xml

我曾尝试反射TechTalk.SpecFlow程序集来查看CreateTestRunnerInstance方法，但是没有找到任何有用的方法来指导我找到解决方案。

生成的步骤文件代码为

// ------------------------------------------------------------------------------
//  <auto-generated>
//      This code was generated by SpecFlow (http://www.specflow.org/).
//      SpecFlow Version:2.1.0.0
//      SpecFlow Generator Version:2.0.0.0
// 
//      Changes to this file may cause incorrect behavior and will be lost if
//      the code is regenerated.
//  </auto-generated>
// ------------------------------------------------------------------------------
#region Designer generated code
#pragma warning disable
namespace Blah.Testing.Specflow
{
    using TechTalk.SpecFlow;


    [System.CodeDom.Compiler.GeneratedCodeAttribute("TechTalk.SpecFlow", "2.1.0.0")]
    [System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
    [NUnit.Framework.TestFixtureAttribute()]
    [NUnit.Framework.DescriptionAttribute("MyTest")]
    public partial class MyTestFeature
    {

        private TechTalk.SpecFlow.ITestRunner testRunner;

#line 1 "MyTest.feature"
#line hidden

        [NUnit.Framework.TestFixtureSetUpAttribute()]
        public virtual void FeatureSetup()
        {
            testRunner = TechTalk.SpecFlow.TestRunnerManager.GetTestRunner();
            TechTalk.SpecFlow.FeatureInfo featureInfo = new TechTalk.SpecFlow.FeatureInfo(new System.Globalization.CultureInfo("en-US"), "MyTest", "\tIn order to avoid silly mistakes\r\n\tAs a math idiot\r\n\tI want to be told the sum o" +
                    "f two numbers", ProgrammingLanguage.CSharp, ((string[])(null)));
            testRunner.OnFeatureStart(featureInfo);
        }

        [NUnit.Framework.TestFixtureTearDownAttribute()]
        public virtual void FeatureTearDown()
        {
            testRunner.OnFeatureEnd();
            testRunner = null;
        }

        [NUnit.Framework.SetUpAttribute()]
        public virtual void TestInitialize()
        {
        }

        [NUnit.Framework.TearDownAttribute()]
        public virtual void ScenarioTearDown()
        {
            testRunner.OnScenarioEnd();
        }

        public virtual void ScenarioSetup(TechTalk.SpecFlow.ScenarioInfo scenarioInfo)
        {
            testRunner.OnScenarioStart(scenarioInfo);
        }

        public virtual void ScenarioCleanup()
        {
            testRunner.CollectScenarioErrors();
        }

        [NUnit.Framework.TestAttribute()]
        [NUnit.Framework.DescriptionAttribute("Add two numbers")]
        [NUnit.Framework.CategoryAttribute("mytag")]
        public virtual void AddTwoNumbers()
        {
            TechTalk.SpecFlow.ScenarioInfo scenarioInfo = new TechTalk.SpecFlow.ScenarioInfo("Add two numbers", new string[] {
                        "mytag"});
#line 7
this.ScenarioSetup(scenarioInfo);
#line 8
 testRunner.Given("I am on the homepage", ((string)(null)), ((TechTalk.SpecFlow.Table)(null)), "Given ");
#line 9
testRunner.Then("I set the Implicit Wait to \"5000\"ms", ((string)(null)), ((TechTalk.SpecFlow.Table)(null)), "Then ");
#line 10
testRunner.Then("I take a screenshot called \"\"", ((string)(null)), ((TechTalk.SpecFlow.Table)(null)), "Then ");
#line hidden
            this.ScenarioCleanup();
        }
    }
}
#pragma warning restore
#endregion

如有任何帮助，将不胜感激