public void IsChangedShouldReturnTrueWhenAnyItemHasBeenChanged()
        {
            // arrange
            var items = new[] { new MockEditableObject(), new MockEditableObject() };

            items[0].FirstName = "test";

            // act
            var changed = items.IsChanged();

            // assert
            Assert.True( changed );
        }
        public void IsChangedShouldReturnFalseWhenNoItemHaveBeenChanged()
        {
            // arrange
            var items = new[] { new MockEditableObject(), new MockEditableObject() };

            // act
            var changed = items.IsChanged();

            // assert
            Assert.False( changed );
        }