public void UndoAllEdit_before_begin_edit()
        {
            MockEntity entity = new MockEntity()
            {
                IntProperty = 1
            };

            Should.Throw <ArgumentNullException>(() => entity.UndoAllEdit());
        }
        public void UndoAllEdit()
        {
            int        before = 1;
            int        after  = 2;
            MockEntity entity = new MockEntity()
            {
                IntProperty = before
            };

            entity.BeginEdit();

            entity.IntProperty = after;
            entity.UndoAllEdit();

            Assert.AreEqual(before, entity.IntProperty);
            Assert.IsTrue(entity.IsEditing);
        }