Fixes for push corner case TAH found a bug where push would push things the remote already had, raising an assertion. This turned out to be because the changeset protocol was not recording a common subset node in one case. Also discovered was that the protocol was queueing multiple copies of a node for pull. Fixed by changing fetch to a hash. Add some more debugging output.

#!/bin/sh

hg init
echo 123 > a
hg add a
hg commit -m "first" -d "0 0" a
mkdir sub
echo 321 > sub/b
hg add sub/b
hg commit -m "second" -d "0 0" sub/b
cat sub/b
hg co 0
cat sub/b
ls sub

true