view contrib/showstack.py @ 51352:7083b33a2699

delta-find: explicitly deal with usage of the cached revision

We can remove this from the general logic path and directly deal with this
corner case early.

This result in a small change in test-generaldelta.t as it turns out that:

- at commit time we (sometimes) precompute a delta against p1 and pass it as the
  cached delta.
- since cached delta where going through the same filtering as everything, we
  could "optimize" the base if it applied to an empty delta, resulting in not
  using the pre-computed delta.

The simpler logic fix the second item, making the cached delta base always actually
tested when requested.

Note that the computation of a fast delta against p1 only is questionable, but
looking into that is out of scope for this series.

# 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)
"""

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