KeyNotFoundException，但调试时没有

Question

我一直在构建一个扩展库，并且我在http://www.extensionmethod.net上使用了一个很好的扩展方法。在我的单元测试中（使用NUnit 1.5.2），我遇到了一个有趣的问题。首先，让我们来看看代码：

/// <summary> 
    /// Groups and aggregates the sequence of elements. 
    /// </summary> 
    /// <typeparam name="TSource">The source type in the sequence.</typeparam> 
    /// <typeparam name="TFirstKey">The first key type to group by.</typeparam> 
    /// <typeparam name="TSecondKey">The second key type to rotate by.</typeparam> 
    /// <typeparam name="TValue">The type of value that will be aggregated.</typeparam> 
    /// <param name="source">The source sequence.</param> 
    /// <param name="firstKeySelector">The first key selector.</param> 
    /// <param name="secondKeySelector">The second key selector.</param> 
    /// <param name="aggregator">The aggregating function.</param> 
    /// <returns>A <see cref="Dictionary{TKey,TValue}" /> representing the pivoted data.</returns>  
    public static Dictionary<TFirstKey, Dictionary<TSecondKey, TValue>> Pivot<TSource, TFirstKey, TSecondKey, TValue> 
     (this IEnumerable<TSource> source, 
     Func<TSource, TFirstKey> firstKeySelector, 
     Func<TSource, TSecondKey> secondKeySelector, 
     Func<IEnumerable<TSource>, TValue> aggregator) 
    { 
     return source.GroupBy(firstKeySelector).Select(
      x => new 
      { 
       X = x.Key, 
       Y = x.GroupBy(secondKeySelector).Select(
        z => new { Z = z.Key, V = aggregator(z) }).ToDictionary(e => e.Z, o => o.V) 
      }).ToDictionary(e => e.X, o => o.Y); 
    } 

功能做什么，是发生在类型TSource的IEnumerable和枢轴转动物品放入一个字典，并使用您定义的任何功能汇总的项目。我的样本数据集是一组人（在一个名为Person的类型中）。

 private static readonly Person[] people = 
     new[] 
     { 
      new Person { Forename = "Matt", Surname = "Someone", Email = "[email protected]", Age = 25, IsMale = true }, 
      new Person { Forename = "Chris", Surname = "Someone", Email = "[email protected]", Age = 28, IsMale = false }, 
      new Person { Forename = "Andy", Surname = "Someone", Email = "[email protected]", Age = 30, IsMale = true }, 
      new Person { Forename = "Joel", Surname = "Someone", Email = "[email protected]", Age = 30, IsMale = true }, 
      new Person { Forename = "Paul", Surname = "Someone", Email = "[email protected]", Age = 30, IsMale = true } 
     }; 

最后，我们做我们的测试：

/// <summary> 
    /// Performs a pivot function on the sample array. 
    /// </summary> 
    [Test] 
    public void Pivot() 
    { 
     /* Our sample data is an array of Person instances. 
     * Let's organise it first by gender (IsMale), and then by Age. 
     * Finally, we'll return a count. */ 
     var organised = people.Pivot(p => p.IsMale, p => p.Age, l => l.Count()); 

     Assert.IsTrue(organised.Count == 2, "More than two genders were returned."); 
     Assert.IsTrue(organised[true].Count == 2, "More than two ages were returned for males."); 
     Assert.IsTrue(organised[false].Count == 1, "More than 1 age was returned for females."); 

     int count = organised[true][30];    
     Assert.IsTrue(count == 3, "There are more than 3 male 30 year olds in our data."); 
    } 

什么在这个测试用例返回，是一个字典>实例。布尔值是IsMale组的结果，在我们的示例数据中，正确地返回2个项目，true和false。内部词典有一个关键的年龄和计数值。在我们的测试数据中，有组织的[true] [30]反映了所有30岁以上的男性。

问题不在于函数本身，而是因为某些原因，当我们通过NUnit测试运行器和Resharper的单元测试运行器运行时，测试失败，报告一行KeyNotFoundException“int count = organized [TRUE] [30];”。当我们调试这个测试时，它正确地返回值3（如在我们的样本数据中，我们有3个30岁的男性）。

有什么想法？

Answer 1

你是否尝试配置NUnit从VS（作为外部程序）运行它？这样你可以让NUint运行你的测试。在调试器下