set -e
set -x

# skip commit logs
export HGMERGE=tkmerge
export EDITOR=true

rm -rf m m1 m2
mkdir m
cd m

echo "m     this  that"
echo "this" > a
echo "that" > b
hg init
hg addremove
hg commit
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ..
echo "m2    this  that "
mkdir m2
cd m2
hg branch ../m
hg checkout
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m
echo "m     this1 that "
echo "this1" > a
hg commit
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ..
echo "m1    this1 that "
mkdir m1
cd m1
hg branch ../m
hg checkout
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m1
echo "m1    this1 that1"
echo "that1" > b
hg commit
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m2
echo "m2    this  that2"
echo "that2" > b
hg commit
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m1
echo "m1:m2 this1 that1 that2"
hg merge ../m2 # b should conflict, a should be fine
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m2
echo "m2    this2 that2"
echo "this2" > a
hg commit
echo "a:" `hg dump a` "b:" `hg dump b`
echo

cd ../m2
echo "m2:m this12 that2"
hg merge ../m # a should conflict, b should be fine
echo "a:" `hg dump a` "b:" `hg dump b`
echo

# now here's the interesting bit
# if we choose ancestor by file, no conflicts
# otherwise we've got two equally close ancestors, each with a conflict
# if we go back to the root, we'll have both conflicts again
echo "m2:m1 this12 that12"
hg merge ../m1 # should be clean
echo "a:" `hg dump a` "b:" `hg dump b`
echo