Store empty (default) branch in branch cache, too.
Operations on this branch don't work otherwise.
Reading branches.cache had to be adjusted to allow an empty label.
Adjusted reading of the cache tip for symmetry, no functional change here.
#!/bin/sh
set -e
mkdir r1
cd r1
hg init
echo a > a
hg addremove
hg commit -m "1" -d "1000000 0"
hg clone . ../r2
cd ../r2
hg up
echo abc > a
hg diff --nodates
cd ../r1
echo b > b
echo a2 > a
hg addremove
hg commit -m "2" -d "1000000 0"
cd ../r2
hg -q pull ../r1
hg status
hg parents
hg --debug up
hg parents
hg --debug up 0
hg parents
hg --debug merge || echo failed
hg parents
hg --debug up
hg parents
hg -v history
hg diff --nodates
# create a second head
cd ../r1
hg up 0
echo b2 > b
echo a3 > a
hg addremove
hg commit -m "3" -d "1000000 0"
cd ../r2
hg -q pull ../r1
hg status
hg parents
hg --debug up || echo failed
hg --debug merge || echo failed
hg --debug merge -f
hg parents
hg diff --nodates
# test a local add
cd ..
hg init a
hg init b
echo a > a/a
echo a > b/a
hg --cwd a commit -A -m a
cd b
hg add a
hg pull -u ../a
hg st