annotate contrib/showstack.py @ 30144:14031d183048

perf: get subsettable from appropriate module for Mercurial earlier than 2.9

Before this patch, using branchmap.subsettable prevents perfbranchmap
from measuring performance of Mercurial earlier than 2.9 (or
175c6fd8cacc), because 175c6fd8cacc moved subsettable from repoview.py
to branchmap.py, even though there are some code paths for Mercurial
earlier than 2.9 in perf.py.

For example, setting "_prereadsize" attribute in perfindex() and
perfnodelookup() is effective only with hg earlier than 1.8 (or
61c9bc3da402).

To get subsettable from appropriate module, this patch examines
existence of subsettable in branchmap and repoview.

This patch also adds check-perf-code.py an extra check entry to detect
direct usage of subsettable attribute in perf.py.

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

from __future__ import absolute_import
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 extsetup(ui):
    signal.signal(signal.SIGQUIT, sigshow)
    try:
        signal.signal(signal.SIGINFO, sigshow)
    except AttributeError:
        pass