c# - 如何使用单元测试断言 Linq 集合

Question

我已经用 LinQ 编写了简单的 group by

public IList dividedNumbersto5(IEnumerable<int> NumberOfCollection)
{
    IList reminderNumber = NumberOfCollection.ToList().GroupBy(g => g%5).OrderBy(g=>g.Key)
        .Select(g => new { Numbers = g, Remindar = g.Key}).ToList();
    return reminderNumber;                              
}

当我尝试测试它时，它说第一个索引项与我的期望不匹配。

var groupingoperators = new GroupingOperators();
IEnumerable<int> numberOfCollection = new List<int>{ 5,14,9,8};
IList remindernumber = groupingoperators.dividedNumbersto5(numberOfCollection);
IList expectedNumberCollection = new List<int>{0,3,4};
CollectionAssert.AreEqual(expectedNumberCollection, remindernumber);

CollectionAssert.AreEqual failed. (Element at index 0 do not match.)

我想知道我应该如何为它编写测试。

Answer 1

你的测试失败的原因是因为:

   "Two collections are equal if they have the same elements 
   in the same order and quantity."

Source

Basically you need to mock your second collection a little better. I think this should work:

IList expectedNumberCollection = new List<object>{
 new {Numbers = new List<int>{5},Remindar=0},
 new {Numbers = new List<int>{8},Remindar=3}, 
 new {Numbers = new List<int>{14,9},Remindar=4}
};