public void IndexerShouldIndexerItemAndRaiseEvents()
        {
            // arrange
            var collection = new ObservableCollection <int>(new[] { 1, 2, 3 });
            var assert     = new Asserter();

            // act, assert (Count and Item[])
            assert.IndexerChangedCollection(collection, 4, 1, c => c[0]);
        }
        public void IndexerShouldIndexerItem()
        {
            // arrange
            var collection = new ObservableCollection <int>(new[] { 1, 2, 3 });
            var assert     = new Asserter();

            // act, assert
            assert.IndexerChangedCollection(collection, 4, 1);
        }