Negative slicing gives unexpected result

This may be related to bug 239767: results[-1:] gives me all of results, but list(results)[-1:] gives me just the last row as I would expect.

It's been pointed out to me that I can use last(), but the -1 is just the test case I hit this with; it's actually a variable in my code.

I've worked around this by reversing the sort order myself and using the absolute value of the slice value. It's ugly though, as the change spans a module boundary.