Petr Baudis wrote:
>>Mercurial's undo is taking a snapshot of all the changed file's repo file length
>>at every commit or pull.  It just truncate the file to original size and undo 
>>is done.
> 
> "Trunactes"? That sounds very wrong... you mean replace with old
> version? Anyway, what if the file has same length? It just doesn't make
> much sense to me.

I believe this works because the files stored in a binary format that 
appends new changesets onto the end. Thus, truncating the new stuff from 
the end effectively removes the commit.

-- 
Andrew Thompson
http://aktzero.com/