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
#
# A B
#
# 3 4 3
# |\/| |\
# |/\| | \
# 1 2 1 2
# \ / \ /
# 0 0
#
# if the result of the merge of 1 and 2
# is the same in 3 and 4, no new manifest
# will be created and the manifest group
# will be empty during the pull
#
# (plus we test a failure where outgoing
# wrongly reported the number of csets)
#
hg init a
cd a
touch init
hg ci -A -m 0 -d "1000000 0"
touch x y
hg ci -A -m 1 -d "1000000 0"
hg update 0
touch x y
hg ci -A -m 2 -d "1000000 0"
hg merge 1
hg ci -A -m m1 -d "1000000 0"
#hg log
#hg debugindex .hg/store/00manifest.i
hg update -C 1
hg merge 2
hg ci -A -m m2 -d "1000000 0"
#hg log
#hg debugindex .hg/store/00manifest.i
cd ..
hg clone -r 3 a b
hg clone -r 4 a c
hg -R a outgoing b
hg -R a outgoing c
hg -R b outgoing c
hg -R c outgoing b
hg -R b pull a
hg -R c pull a