RecyclableLongList.Enumerator restored as the issue was somewhere else.

Recyclable.Collections/RecyclableLongList.Enumerator.cs

@@ -26,7 +26,7 @@ namespace Recyclable.Collections
 			{
 				var list = _list;
 
-				if (_currentBlockIndex <= list._lastBlockWithData && _currentItemIndex <= (_currentBlockIndex == list._lastBlockWithData && list._nextItemIndex > 0 ? list._nextItemIndex - 1: list._blockSizeMinus1))
+				if (_currentBlockIndex < list._lastBlockWithData)
 				{
 					_current = list._memoryBlocks[_currentBlockIndex][_currentItemIndex];
 					if (_currentItemIndex + 1 < list._blockSize)
@@ -41,7 +41,14 @@ namespace Recyclable.Collections
 
 					return true;
 				}
+
 				// Move to the next item if we're within block boundaries, otherwise report end of collection.
+				if (list._longCount > 0 && _currentItemIndex < (list._nextItemIndex > 0 ? list._nextItemIndex : list._blockSize))
+				{
+					_current = list._memoryBlocks[_currentBlockIndex][_currentItemIndex];
+					_currentItemIndex++;
+					return true;
+				}
 
 				return false;
 			}