Robin Farine <robin.farine@terminus.org> [Tue, 28 Feb 2006 23:47:40 -0800] rev 1822
copy/rename to a removed destination file
When the destination of a copy or rename operation has been
marked for removal, we need to restore it before we overwrite
it with the new content. This also handles the case of
idempotent renames, i.e.
hg rename "a" "b"
hg rename "b" "a"