Issue a warning if "-r ." is used with two working directory parents. Rationale for not aborting instead: The first parent is usually more important as it is the local branch during a merge and commands like 'hg diff' and 'hg diff -r.' behave still identically (except for the warning of course). Added a test for log -r. with one and two parents.

#!/bin/sh

hg init
touch unknown

touch a
hg add a
hg ci -m "1" -d "1000000 0"

touch b
hg add b
hg ci -m "2" -d "1000000 0"

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