public void When_CopyingToArray_Expect_CopiedToArray() { // Arrange OrderBy orderBy1 = new OrderBy(nameof(TestClass.Property1)); OrderBy orderBy2 = new OrderBy(nameof(TestClass.Property2)); OrderBy orderBy3 = new OrderBy(nameof(TestClass.Property3)); Ordering <TestClass> ordering = new Ordering <TestClass> { orderBy1, orderBy2, orderBy3, }; OrderBy[] array = new OrderBy[5]; // Act ordering.CopyTo(array, 1); // Assert Assert.Null(array[0]); Assert.Equal(orderBy1, array[1]); Assert.Equal(orderBy2, array[2]); Assert.Equal(orderBy3, array[3]); Assert.Null(array[4]); }