contrib/showstack.py

check-code: detect "missing _() in ui message" more exactly

Before this patch, "missing _() in ui message" rule overlooks
translatable message, which starts with other than alphabet.

To detect "missing _() in ui message" more exactly, this patch
improves the regexp with assumptions below.

  - sequence consisting of below might precede "translatable message"
    in same string token

    - formatting string, which starts with '%'
    - escaped character, which starts with 'b' (as replacement of '\\'), or
    - characters other than '%', 'b' and 'x' (as replacement of alphabet)

  - any string tokens might precede a string token, which contains
    "translatable message"

This patch builds an input file, which is used to examine "missing _()
in ui message" detection, before '"$check_code" stringjoin.py' in
test-contrib-check-code.t, because this reduces amount of change churn
in subsequent patch.

This patch also applies "()" instead of "_()" on messages below to
hide false-positives:

  - messages for ui.debug() or debug commands/tools
    - contrib/debugshell.py
    - hgext/win32mbcs.py (ui.write() is used, though)
    - mercurial/commands.py
      - _debugchangegroup
      - debugindex
      - debuglocks
      - debugrevlog
      - debugrevspec
      - debugtemplate

  - untranslatable messages
    - doc/gendoc.py (ReST specific text)
    - hgext/hgk.py (permission string)
    - hgext/keyword.py (text written into configuration file)
    - mercurial/cmdutil.py (formatting strings for JSON)

# 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