absorb: preserve changesets which were already empty
Most commands in Mercurial (commit, rebase, absorb itself) don’t create empty
changesets or drop them if they become empty. If there’s a changeset that’s
empty, it must be a deliberate choice of the user. At least it shouldn’t be
absorb’s responsibility to prune them. The fact that changesets that became
empty during absorb are pruned, is unaffected by this.
This case was found while writing patches which make it possible to configure
absorb and rebase to not drop empty changesets. Even without having such config
set, I think it’s valuable to preserve changesets which were already empty.
# Disable the $CAP wire protocol capability.
if test -z "$CAP"
then
echo "CAP environment variable not set."
fi
cat > notcapable-$CAP.py << EOF
from mercurial import extensions, localrepo
from mercurial.interfaces import repository
def extsetup(ui):
extensions.wrapfunction(repository.peer, 'capable', wrapcapable)
extensions.wrapfunction(localrepo.localrepository, 'peer', wrappeer)
def wrapcapable(orig, self, name, *args, **kwargs):
if name in b'$CAP'.split(b' '):
return False
return orig(self, name, *args, **kwargs)
def wrappeer(orig, self):
# Since we're disabling some newer features, we need to make sure local
# repos add in the legacy features again.
return localrepo.locallegacypeer(self)
EOF
echo '[extensions]' >> $HGRCPATH
echo "notcapable-$CAP = `pwd`/notcapable-$CAP.py" >> $HGRCPATH