Priority Queue Contains Test

PriorityQueueTest.cs

public class PriorityQueueTest
{
  
  [Fact]
  public void ContainsOnlyEnqueuedItems()
  {
      // Arrange
      var jdoe = new Patient { Id = 3, Triage = 1 };
      var jsmith = new Patient { Id = 5, Triage = 3 };
      var unqueued = new Patient { Id = 7, Triage = 3 };

      var sut = new PriorityQueue<Patient>(Patient.TriageComparer);
      sut.Enqueue(jdoe);
      sut.Enqueue(jsmith);

      // Act && Assert
      Assert.True(sut.Contains(jdoe));
      Assert.True(sut.Contains(jsmith));
      Assert.False(sut.Contains(unqueued));
  }
  
  private class Patient
  {
      public static readonly IComparer<Patient> TriageComparer = 
          new ByTriage();
      public int Id { get; set; }
      public string MRN { get; set; }
      public int Triage { get; set; }

      public override bool Equals(object obj)
      {
          if (ReferenceEquals(this, obj)) return true;
          var other = obj as Patient;
          if (other == null) return false;
          return Id.Equals(other.Id);
      }

      public override int GetHashCode()
      {
          return Id.GetHashCode();
      }

      private class ByTriage : IComparer<Patient>
      {
          public int Compare(Patient x, Patient y)
          {
              if (x == null && y == null) return 0;
              if (x == null) return -1;
              if (y == null) return 1;
              return x.Triage - y.Triage;
          }
      }
  }
}