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

mkdir alpha
touch alpha/one
mkdir beta
touch beta/two

hg add alpha/one beta/two
hg ci -m "start" -d "1000000 0"

echo 1 > alpha/one
echo 2 > beta/two

echo EVERYTHING
hg diff --nodates

echo BETA ONLY
hg diff --nodates beta

echo INSIDE BETA
cd beta
hg diff --nodates .