[MERGE] #303568: tree lock is not released after a failing attempt at shelving an unversioned file

[Aaron Bentley]

Benoît PIERRE wrote:
> On 2009-03-02 19:27:33, Martin Pool wrote:
>> Martin Pool has voted resubmit.
>> Status is now: Resubmit
>> Comment:
>> I agree with John, it does seem like you need to defer this until the  
>> iterator is run.
>>
>> The name 'finalize' seems to imply you can run it from a finally block  
>> which would be cleaner than a bare except block.
>>
>> Is there maybe also a blackbox test for unshelve where you could add a  
>> test for this case.
> 
> A "PathsNotVersionedError" exception can be raised during the
> iterator setup. I added a test to test_shelf.py.

bb:tweak

As Martin noted, a try/finally block is a cleaner way of doing this.
Since this change is small, I'll apply this and submit it.

Aaron