NUnit，Assert失败后是否可以继续执行测试？

Question

在包含一些断言的测试中，例如：

Assert.AreEqual(1,1);
Assert.AreEqual(2,1);
Assert.AreEqual(2,2);

是否有可能让测试在某些时候失败后继续运行？在该示例中，第一个条件为真，第二个条件失败并且测试停止。我还要评估以下条件。

Answer 1

NUnit 3.6添加了Assert.Multiple方法和MultipleAsserts属性。

见https://github.com/nunit/docs/wiki/Multiple-Asserts。

Answer 2

我更喜欢实用，并在一种方法中放入几个相关的断言。

我有一个辅助类，它启用以下语法（我使用）：

AssertAll.Succeed(
    () => Assert.AreEqual("bb", id.Context),
    () => Assert.AreEqual("abc", id.FullName),
    () => Assert.AreEqual("b", id.SessionID));

这给了我这样的错误信息：

Assert.AreEqual failed. Expected:<bb>. Actual:<b\c>. 
Assert.AreEqual failed. Expected:<abc>. Actual:<[b\c]a{103}>. 
at FXP_COM.Tests.EnumToStringConverterterTests.<>c__DisplayClass3.<ShouldConvert>b__0() in UnitTest1.cs: line 31
at FXP_COM.Tests.AssertAll.Succeed(Action[] assertions) in UnitTest1.cs: line 46 at FXP_COM.Tests.AssertAll.Succeed(Action[] assertions) in UnitTest1.cs: line 62
at FXP_COM.Tests.EnumToStringConverterterTests.ShouldConvert() in UnitTest1.cs: line 30

辅助类如下：

using System;
using NUnit.Framework;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;

public static class AssertAll
{
    public static void Succeed(params Action[] assertions)
    {
        var errors = new List<Exception>();

        foreach (var assertion in assertions)
            try
            {
                assertion();
            }
            catch (Exception ex)
            {
                errors.Add(ex);
            }

        if (errors.Any())
        {
            var ex = new AssertionException(
                string.Join(Environment.NewLine, errors.Select(e => e.Message)),
                errors.First());

            // Use stack trace from the first exception to ensure first
            // failed Assert is one click away
            ReplaceStackTrace(ex, errors.First().StackTrace);

            throw ex;
        }
    }

    static void ReplaceStackTrace(Exception exception, string stackTrace)
    {
        var remoteStackTraceString = typeof(Exception)
            .GetField("_remoteStackTraceString",
                BindingFlags.Instance | BindingFlags.NonPublic);

        remoteStackTraceString.SetValue(exception, stackTrace);
    }
}

Answer 3

通常在这种情况下，您可以将断言上方的所有代码放入设置方法中，然后将每个断言写入自己的测试用例。

Answer 4

不，你不能单独使用NUnit。你必须做像@Konstantin Spirin这样的事情。我创建了一个可以使用的小扩展;它被称为NUnit-GroupAssert。它可以在这里找到：https://github.com/slvnperron/NUnit-GroupAssert

如何使用它：

[Test]
public void Verify_GroupsExceptions()
{
    var group = new AssertGroup();
    group.Add(() => Assert.AreEqual(10, 20));
    group.Add(() => Assert.AreEqual(1, 1));
    group.Add(() => Assert.AreEqual(3, 4));
    group.Add(() => Assert.IsTrue(1 > 3));
    group.Verify();
}

// OR

public void Verify_GroupsExceptions()
{
    // Verifies on disposal
    using (var group = new AssertGroup())
    {
        group.Add(() => Assert.AreEqual(10, 20));
        group.Add(() => Assert.AreEqual(1, 1));
        group.Add(() => Assert.AreEqual(3, 4));
        group.Add(() => Assert.IsTrue(1 > 3));
    }
}

它将输出：

测试失败，因为一个或多个断言失败： 1）预期：10 但是：20 来自第18行的Verify_GroupsExceptions

2）预期：3 但是：4 来自第20行的Verify_GroupsExceptions

3）预期：是的 但是：是的 来自第21行的Verify_GroupsExceptions

Answer 5

你可以稍微作弊而不是在给定点上实际失败，而是标记失败，然后在最后失败，如下所示：

var sbError = new StringBuilder();
if (!SomeCondition()) {
  sbError.AppendLine("SomeCondition failed");
}
if (!SomeOtherCondition()) {
  sbError.AppendLine("SomeOtherCondition failed");
}
Assert.AreEqual(0, sbError.Length, sbError.ToString());

我不推荐这个，但如果你需要做一两次，那应该不会那么糟糕。

Answer 6

不。无论如何，每次测试都不应该有多个断言，这样可以减少分离，并且更难以找出哪个失败。

如果您有许多需要在Assert之前执行的代码，请将其分离为[SetUp]函数，或将其作为单独的过程。

Answer 7

断言如果失败则抛出NUnit.Framework.AssertionException。您可以在第二个断言上捕获该异常，评估第三个断言，然后重新抛出异常。

不过，出于Ed Woodcock和Carl Manaster所指出的原因，这并不是我推荐的。

Answer 8

您可以重新构建测试以将断言包装在try / catch块中并跟踪它们以供以后验证。但是，我不建议这样做。如果您希望独立测试，您应该对每种情况使用单独的测试。

  bool[] assertionSuccesses = new bool[] { false, false, false };

  try
  {
       Assert.AreEqual( 1, 1 );
       assertionSuccesses[0] = true;
  }
  catch (AssertionException) {}
  ...

  if (assertionSuccesses.Any( s => !s ))
  {
       Assert.Fail("one of the assertions failed");
  }

Answer 9

我将Konstantin Spirin的代码示例重写为VB。

Imports NUnit.Framework
Imports System.Reflection

Public Class Group_LIB_NUnit_Assert_Multiple

    Public Shared Sub Multiple(ParamArray Assertions As Action())
        Dim ExceptionObj As Exception
        Dim Exceptions As New List(Of Exception)
        Dim Message As String

        For Each Assertion In Assertions
            Try
                Assertion()
            Catch ex As Exception
                Exceptions.Add(ex)
            End Try
        Next

        If Exceptions.Count > 0 Then
            Message = String.Format("{0}{1} assertions failed: {2}{3}", Environment.NewLine, Exceptions.Count, Environment.NewLine, String.Join(Environment.NewLine, Exceptions.Select(Function(e) e.Message).ToList()))

            ExceptionObj = New AssertionException(Message)

            StackTraceReplace(ExceptionObj, Exceptions.First.StackTrace)

            Throw ExceptionObj
        End If
    End Sub

    Public Shared Sub StackTraceReplace(ExceptionObj As Exception, StackTrace As String)
        Dim RemoteStackTraceString As FieldInfo

        RemoteStackTraceString = GetType(Exception).GetField("_remoteStackTraceString", Reflection.BindingFlags.Instance Or Reflection.BindingFlags.NonPublic)

        RemoteStackTraceString.SetValue(ExceptionObj, StackTrace)

    End Sub
End Class

Imports Group.Library4
Imports NUnit.Framework

<TestFixture()> _
Public Class TEST_Group_LIB_NUnit_Assert_Multiple

    <Test()> _
    <TestCaseSource("Factory")> _
    Public Sub Multiple(TestObj As TEST_DATA_Group_LIB_NUnit_Assert_Multiple)

        Group_LIB_NUnit_Assert_Multiple.Multiple(Sub() Assert.That(TestObj.Gender, [Is].EqualTo("F"c), "Gender"), Sub() Assert.That(TestObj.Name, [Is].EqualTo("George Washington"), "Name"))
    End Sub

    Public Function Factory() As List(Of TEST_DATA_Group_LIB_NUnit_Assert_Multiple)
        Dim L As New List(Of TEST_DATA_Group_LIB_NUnit_Assert_Multiple)
        Dim TestObj As TEST_DATA_Group_LIB_NUnit_Assert_Multiple

        TestObj = New TEST_DATA_Group_LIB_NUnit_Assert_Multiple()
        TestObj.DOB = New DateTime(2015, 8, 12)
        TestObj.Gender = "M"c
        TestObj.Name = "Abraham Lincoln"
        L.Add(TestObj)

        TestObj = New TEST_DATA_Group_LIB_NUnit_Assert_Multiple()
        TestObj.DOB = New DateTime(2015, 8, 12)
        TestObj.Gender = "F"c
        TestObj.Name = "George Washington"
        L.Add(TestObj)

        TestObj = New TEST_DATA_Group_LIB_NUnit_Assert_Multiple()
        TestObj.DOB = New DateTime(2015, 8, 12)
        TestObj.Gender = "A"c
        TestObj.Name = "John Hancock"
        L.Add(TestObj)

        Return L
    End Function
End Class

Public Class TEST_DATA_Group_LIB_NUnit_Assert_Multiple

    Public Property DOB As Date

    Public Property Gender As Char

    Public Property Name As String

End Class