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
hg init repo
cd repo
touch foo
hg add foo
for i in 0 1 2 3 4 5 6 7 8 9 10 11; do
echo "foo-$i" >> foo
hg ci -m "foo-$i" -d "0 0"
done
for out in "%nof%N" "%%%H" "%b-%R" "%h" "%r"; do
echo "# foo-$out.patch"
hg export -v -o "foo-$out.patch" 2:tip
done