automation: shore up rebooting behavior
There was a race condition in the old code. Use
instance.stop()/instance.start() to eliminate it.
As part of debugging this, I also found another race condition
related to PowerShell permissions after the reboot. Unfortunately,
I'm not sure the best way to work around it. I've added a comment
for now.
Differential Revision: https://phab.mercurial-scm.org/D6288
#!/usr/bin/env python
# Filters traceback lines from stdin.
from __future__ import absolute_import, print_function
import sys
state = 'none'
for line in sys.stdin:
if state == 'none':
if line.startswith('Traceback '):
state = 'tb'
elif state == 'tb':
if line.startswith(' File '):
state = 'file'
continue
elif not line.startswith(' '):
state = 'none'
elif state == 'file':
# Ignore lines after " File "
state = 'tb'
continue
print(line, end='')