view mercurial/i18n.py @ 23031:3c0983cc279e

i18n: cache the result of every gettext call In looking at profiler output for 'hg log' on mozilla-central, I noticed we spent a _huge_ amount of time in gettext relative to what it's doing. Caching provides a roughly 15% performance improvement even on repositories as small as hg. == hg repo on linux == Before: % cumulative self time seconds seconds name 5.05 0.19 0.19 i18n.py:62:gettext 4.84 0.18 0.18 revlog.py:88:decompress 2.95 0.17 0.11 changelog.py:201:node 2.32 0.09 0.09 ui.py:577:write 2.11 0.08 0.08 i18n.py:72:gettext 2.11 0.08 0.08 obsolete.py:196:_fm0readmarkers 1.89 0.07 0.07 obsolete.py:569:_load 1.68 0.63 0.06 localrepo.py:29:__get__ real 0m4.026s user 0m3.993s sys 0m0.034s After: % cumulative self time seconds seconds name 8.05 0.26 0.26 revlog.py:88:decompress 2.68 0.22 0.09 color.py:395:write 2.20 0.07 0.07 obsolete.py:196:_fm0readmarkers 1.95 0.06 0.06 obsolete.py:174:_fm0readmarkers 1.95 0.06 0.06 ui.py:577:write 1.95 0.06 0.06 util.py:1228:datestr 1.71 0.06 0.06 utf_8.py:16:decode 1.71 0.06 0.06 revlog.py:273:__len__ real 0m3.519s user 0m3.447s sys 0m0.073s == mozilla-central repo on linux == Before: % cumulative self time seconds seconds name 7.72 2.35 2.35 revlog.py:88:decompress 4.46 1.36 1.36 i18n.py:62:gettext 2.22 0.67 0.67 i18n.py:72:gettext 2.19 1.14 0.67 changelog.py:201:node 2.16 0.66 0.66 ui.py:577:write 1.96 0.60 0.60 utf_8.py:16:decode 1.93 1.97 0.59 color.py:395:write 1.85 0.81 0.56 changelog.py:136:tip real 0m30.822s user 0m30.660s sys 0m0.149s After: % cumulative self time seconds seconds name 9.82 2.49 2.49 revlog.py:88:decompress 2.67 1.31 0.68 localrepo.py:29:__get__ 2.57 0.65 0.65 utf_8.py:16:decode 2.48 1.01 0.63 changelog.py:201:node 2.10 0.82 0.53 changelog.py:136:tip 2.01 0.51 0.51 ui.py:577:write 1.91 0.49 0.49 util.py:1232:datestr 1.85 1.65 0.47 color.py:395:write real 0m25.619s user 0m25.446s sys 0m0.166s == cpython repo on os x = Before: % cumulative self time seconds seconds name 5.05 1.35 1.35 cmdutil.py:982:_show 4.59 1.22 1.22 revlog.py:274:__len__ 3.98 1.06 1.06 i18n.py:62:gettext 3.91 1.04 1.04 revlog.py:1016:revision 3.68 0.98 0.98 revlog.py:337:parents 3.45 0.92 0.92 revlog.py:88:decompress 2.91 0.78 0.78 revlog.py:309:rev 2.62 0.70 0.70 revlog.py:1033:revision real 0m30.414s user 0m28.145s sys 0m0.541s After: % cumulative self time seconds seconds name 7.98 1.66 1.66 cmdutil.py:982:_show 6.83 1.42 1.42 changelog.py:46:decodeextra 5.18 1.08 1.08 revlog.py:274:__len__ 3.94 0.82 0.82 revlog.py:1016:revision 3.41 0.71 0.71 revlog.py:309:rev 3.32 0.69 0.69 revlog.py:88:decompress 2.99 0.63 0.62 revlog.py:1033:revision 2.69 0.56 0.56 revlog.py:341:start real 0m22.811s user 0m21.883s sys 0m0.397s
author Augie Fackler <raf@durin42.com>
date Fri, 17 Oct 2014 13:52:10 -0400
parents 0d0350cfc7ab
children 2c07c6884394
line wrap: on
line source

# i18n.py - internationalization support for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import encoding
import gettext as gettextmod, sys, os, locale

# modelled after templater.templatepath:
if getattr(sys, 'frozen', None) is not None:
    module = sys.executable
else:
    module = __file__


_languages = None
if (os.name == 'nt'
    and 'LANGUAGE' not in os.environ
    and 'LC_ALL' not in os.environ
    and 'LC_MESSAGES' not in os.environ
    and 'LANG' not in os.environ):
    # Try to detect UI language by "User Interface Language Management" API
    # if no locale variables are set. Note that locale.getdefaultlocale()
    # uses GetLocaleInfo(), which may be different from UI language.
    # (See http://msdn.microsoft.com/en-us/library/dd374098(v=VS.85).aspx )
    try:
        import ctypes
        langid = ctypes.windll.kernel32.GetUserDefaultUILanguage()
        _languages = [locale.windows_locale[langid]]
    except (ImportError, AttributeError, KeyError):
        # ctypes not found or unknown langid
        pass

_ugettext = None

def setdatapath(datapath):
    localedir = os.path.join(datapath, 'locale')
    t = gettextmod.translation('hg', localedir, _languages, fallback=True)
    global _ugettext
    _ugettext = t.ugettext

_msgcache = {}

def gettext(message):
    """Translate message.

    The message is looked up in the catalog to get a Unicode string,
    which is encoded in the local encoding before being returned.

    Important: message is restricted to characters in the encoding
    given by sys.getdefaultencoding() which is most likely 'ascii'.
    """
    # If message is None, t.ugettext will return u'None' as the
    # translation whereas our callers expect us to return None.
    if message is None or not _ugettext:
        return message

    if message not in _msgcache:
        if type(message) is unicode:
            # goofy unicode docstrings in test
            paragraphs = message.split(u'\n\n')
        else:
            paragraphs = [p.decode("ascii") for p in message.split('\n\n')]
        # Be careful not to translate the empty string -- it holds the
        # meta data of the .po file.
        u = u'\n\n'.join([p and _ugettext(p) or '' for p in paragraphs])
        try:
            # encoding.tolocal cannot be used since it will first try to
            # decode the Unicode string. Calling u.decode(enc) really
            # means u.encode(sys.getdefaultencoding()).decode(enc). Since
            # the Python encoding defaults to 'ascii', this fails if the
            # translated string use non-ASCII characters.
            _msgcache[message] = u.encode(encoding.encoding, "replace")
        except LookupError:
            # An unknown encoding results in a LookupError.
            _msgcache[message] = message
    return _msgcache[message]

def _plain():
    if 'HGPLAIN' not in os.environ and 'HGPLAINEXCEPT' not in os.environ:
        return False
    exceptions = os.environ.get('HGPLAINEXCEPT', '').strip().split(',')
    return 'i18n' not in exceptions

if _plain():
    _ = lambda message: message
else:
    _ = gettext