contrib/memory.py

replace Python standard textwrap by MBCS sensitive one for i18n text

Mercurial has problem around text wrapping/filling in MBCS encoding
environment, because standard 'textwrap' module of Python can not
treat it correctly. It splits byte sequence for one character into two
lines.

According to unicode specification, "east asian width" classifies
characters into:

   W(ide), N(arrow), F(ull-width), H(alf-width), A(mbiguous)


W/N/F/H can be always recognized as 2/1/2/1 bytes in byte sequence,
but 'A' can not. Size of 'A' depends on language in which it is used.

Unicode specification says:

   If the context(= language) cannot be established reliably they
   should be treated as narrow characters by default

but many of class 'A' characters are full-width, at least, in Japanese
environment.

So, this patch treats class 'A' characters as full-width always for
safety wrapping.

This patch focuses only on MBCS safe-ness, not on writing/printing
rule strict wrapping for each languages

MBCS sensitive textwrap class is originally implemented
by ITO Nobuaki <[e-mail]>.

# memory.py - track memory usage
#
# Copyright 2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''helper extension to measure memory usage

Reads current and peak memory usage from ``/proc/self/status`` and
prints it to ``stderr`` on exit.
'''

import atexit

def memusage(ui):
    """Report memory usage of the current process."""
    status = None
    result = {'peak': 0, 'rss': 0}
    try:
        # This will only work on systems with a /proc file system
        # (like Linux).
        status = open('/proc/self/status', 'r')
        for line in status:
            parts = line.split()
            key = parts[0][2:-1].lower()
            if key in result:
                result[key] = int(parts[1])
    finally:
        if status is not None:
            status.close()
    ui.write_err(", ".join(["%s: %.1f MiB" % (key, value / 1024.0)
                            for key, value in result.iteritems()]) + "\n")

def extsetup(ui):
    atexit.register(memusage, ui)