This fixes a bug that Chris Mason found. As for a test case, I can't think of one. It's a very weird case. Basically, if there is a file listed as changed in the changelog entry, but not showing up in any of the associated manifest entries, hg would abort when trying to create a changeset. Now it just decides the file must not have any versions relevant to the changeset.

#!/bin/sh

hg init
touch unknown

touch a
hg add a
hg ci -m "1" -d "0 0"

touch b
hg add b
hg ci -m "2" -d "0 0"

echo %% Should show unknown
hg status
hg revert -r 0
echo %% Should show unknown and b removed
hg status
echo %% Should show a and unknown
ls