contrib/showstack.py

localrepo: delete obsolete comment about `prefix in repo` raising exception

We dropped support for `prefix in repo`, where `prefix` is a hex
prefix, in 8b86acc7aa64 (context: drop support for looking up context
by ambiguous changeid (API), 2018-04-28), after having deprecated it a
while before that. These days you get a `ProgrammingError` instead if
you pass in a short nodeid.

Differential Revision: https://phab.mercurial-scm.org/D9599

# showstack.py - extension to dump a Python stack trace on signal
#
# binds to both SIGQUIT (Ctrl-\) and SIGINFO (Ctrl-T on BSDs)
r"""dump stack trace when receiving SIGQUIT (Ctrl-\) or SIGINFO (Ctrl-T on BSDs)
"""

from __future__ import absolute_import, print_function
import signal
import sys
import traceback


def sigshow(*args):
    sys.stderr.write("\n")
    traceback.print_stack(args[1], limit=10, file=sys.stderr)
    sys.stderr.write("----\n")


def sigexit(*args):
    sigshow(*args)
    print('alarm!')
    sys.exit(1)


def extsetup(ui):
    signal.signal(signal.SIGQUIT, sigshow)
    signal.signal(signal.SIGALRM, sigexit)
    try:
        signal.signal(signal.SIGINFO, sigshow)
    except AttributeError:
        pass