contrib/showstack.py

run-tests: fix whitelist/blacklist with directories on Windows

The file name is resolved with `os.path.relpath()` in the `Test` constructor,
which yields `\` on Windows.  That doesn't match the `/` separator when using
MSYS tools to build the list, and it isn't obvious that this is the problem
because directory separators can mostly be used interchangeably.  The
`--test-list` argument already seems to be properly handled.

# 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