Mockowanie IEnumerable/IEnumerator z fakeiteasy

  1:  private IEnumerable<T> create_fake_enumerable<T>(params T[] items)
  2:  {
  3:      var enumerable = A.Fake<IEnumerable<T>>();
  4:      var enumerator = A.Fake<IEnumerator<T>>();
  5:  
  6:      A.CallTo(() => enumerable.GetEnumerator())
  7:          .Returns(enumerator);
  8:  
  9:      // fake configuration is LIFO ->
 10:      // -> define last action first
 11:      A.CallTo(() => enumerator.MoveNext())
 12:          .Returns(false)
 13:          .Once();
 14:  
 15:      // define true for each element in enumerator
 16:      // overriding earlier configuration
 17:      A.CallTo(() => enumerator.MoveNext())
 18:          .Returns(true)
 19:          .NumberOfTimes(items.Length);
 20:  
 21:      A.CallTo(() => enumerator.Current)
 22:          .ReturnsNextFromSequence(items);
 23:  
 24:      return enumerable;
 25:  }
 26:  
 27:  [Fact]
 28:  public void is_usable_in_linq()
 29:  {
 30:      var enumerable = create_fake_enumerable(3, 6, 9);
 31:  
 32:      var between4and9 = enumerable.Where(x => x > 4 && x < 9);
 33:  
 34:      Assert.Equal(1, between4and9.Count());
 35:  }
 36:  
 37:  [Fact]
 38:  public void is_usable_in_foreach()
 39:  {
 40:      var enumerable = create_fake_enumerable(6, 6, 6, 6);
 41:  
 42:      int counter = 0;
 43:  
 44:      foreach (var number in enumerable)
 45:      {
 46:          Assert.Equal(6, number);
 47:          counter++;
 48:      }
 49:  
 50:      Assert.Equal(4, counter);
 51:  }