typing: add an assertion to util.versiontuple
Fixes the following warning:
line 1177, in versiontuple: No attribute 'split' on None [attribute-error]
In Optional[bytes]
Differential Revision: https://phab.mercurial-scm.org/D7676
--- a/mercurial/util.py Sun Dec 15 21:28:30 2019 -0500
+++ b/mercurial/util.py Sun Dec 15 21:36:06 2019 -0500
@@ -1173,6 +1173,8 @@
else:
vparts, extra = m.group(1), None
+ assert vparts is not None # help pytype
+
vints = []
for i in vparts.split(b'.'):
try: