mktag
mustsucceed $push_spec # succeeds
+mktag
+mustfail 'push is missing head ref update' $push_spec
+
+git commit --allow-empty -m 'Dummy update'
mktag
mustfail 'not replacing previously-pushed version' $push_spec
+git reset --hard HEAD~
prep_dm_mangle () {
prep unstable sid