public void Insert_OneItemAtSecondIndex_ItemIsAddedAndCollectionChangedRaised()
{
var collectionChangedEventArgsList = new List <NotifyCollectionChangedEventArgs>();
var collection = new ExtendedObservableCollection <int> {
123, 456, 789
};
collection.CollectionChanged += (_, args) => collectionChangedEventArgsList.Add(args);
collection.Insert(1, 0);
Assert.Equal(4, collection.Count);
Assert.Equal(new[] { 123, 0, 456, 789 }, collection);
Assert.Single(collectionChangedEventArgsList);
Assert.Equal(NotifyCollectionChangedAction.Add, collectionChangedEventArgsList[0].Action);
Assert.NotNull(collectionChangedEventArgsList[0].NewItems);
Assert.Single(collectionChangedEventArgsList[0].NewItems);
Assert.Equal(0, collectionChangedEventArgsList[0].NewItems[0]);
}
