Source code for django.utils.translation

"""
Internationalization support.
"""
from __future__ import unicode_literals

import re

from django.utils import six
from django.utils.decorators import ContextDecorator
from django.utils.encoding import force_text
from django.utils.functional import lazy

__all__ = [
    'activate', 'deactivate', 'override', 'deactivate_all',
    'get_language', 'get_language_from_request',
    'get_language_info', 'get_language_bidi',
    'check_for_language', 'to_locale', 'templatize', 'string_concat',
    'gettext', 'gettext_lazy', 'gettext_noop',
    'ugettext', 'ugettext_lazy', 'ugettext_noop',
    'ngettext', 'ngettext_lazy',
    'ungettext', 'ungettext_lazy',
    'pgettext', 'pgettext_lazy',
    'npgettext', 'npgettext_lazy',
    'LANGUAGE_SESSION_KEY',
]

LANGUAGE_SESSION_KEY = '_language'


class TranslatorCommentWarning(SyntaxWarning):
    pass


# Here be dragons, so a short explanation of the logic won't hurt:
# We are trying to solve two problems: (1) access settings, in particular
# settings.USE_I18N, as late as possible, so that modules can be imported
# without having to first configure Django, and (2) if some other code creates
# a reference to one of these functions, don't break that reference when we
# replace the functions with their real counterparts (once we do access the
# settings).

class Trans(object):
    """
    The purpose of this class is to store the actual translation function upon
    receiving the first call to that function. After this is done, changes to
    USE_I18N will have no effect to which function is served upon request. If
    your tests rely on changing USE_I18N, you can delete all the functions
    from _trans.__dict__.

    Note that storing the function with setattr will have a noticeable
    performance effect, as access to the function goes the normal path,
    instead of using __getattr__.
    """

    def __getattr__(self, real_name):
        from django.conf import settings
        if settings.USE_I18N:
            from django.utils.translation import trans_real as trans
        else:
            from django.utils.translation import trans_null as trans
        setattr(self, real_name, getattr(trans, real_name))
        return getattr(trans, real_name)

_trans = Trans()

# The Trans class is no more needed, so remove it from the namespace.
del Trans


[docs]def gettext_noop(message): return _trans.gettext_noop(message)
ugettext_noop = gettext_noop
[docs]def gettext(message): return _trans.gettext(message)
[docs]def ngettext(singular, plural, number): return _trans.ngettext(singular, plural, number)
[docs]def ugettext(message): return _trans.ugettext(message)
[docs]def ungettext(singular, plural, number): return _trans.ungettext(singular, plural, number)
[docs]def pgettext(context, message): return _trans.pgettext(context, message)
[docs]def npgettext(context, singular, plural, number): return _trans.npgettext(context, singular, plural, number)
gettext_lazy = lazy(gettext, str) ugettext_lazy = lazy(ugettext, six.text_type) pgettext_lazy = lazy(pgettext, six.text_type) def lazy_number(func, resultclass, number=None, **kwargs): if isinstance(number, six.integer_types): kwargs['number'] = number proxy = lazy(func, resultclass)(**kwargs) else: class NumberAwareString(resultclass): def __mod__(self, rhs): if isinstance(rhs, dict) and number: try: number_value = rhs[number] except KeyError: raise KeyError('Your dictionary lacks key \'%s\'. ' 'Please provide it, because it is required to ' 'determine whether string is singular or plural.' % number) else: number_value = rhs kwargs['number'] = number_value translated = func(**kwargs) try: translated = translated % rhs except TypeError: # String doesn't contain a placeholder for the number pass return translated proxy = lazy(lambda **kwargs: NumberAwareString(), NumberAwareString)(**kwargs) return proxy
[docs]def ngettext_lazy(singular, plural, number=None): return lazy_number(ngettext, str, singular=singular, plural=plural, number=number)
[docs]def ungettext_lazy(singular, plural, number=None): return lazy_number(ungettext, six.text_type, singular=singular, plural=plural, number=number)
[docs]def npgettext_lazy(context, singular, plural, number=None): return lazy_number(npgettext, six.text_type, context=context, singular=singular, plural=plural, number=number)
[docs]def activate(language): return _trans.activate(language)
[docs]def deactivate(): return _trans.deactivate()
[docs]class override(ContextDecorator): def __init__(self, language, deactivate=False): self.language = language self.deactivate = deactivate def __enter__(self): self.old_language = get_language() if self.language is not None: activate(self.language) else: deactivate_all() def __exit__(self, exc_type, exc_value, traceback): if self.old_language is None: deactivate_all() elif self.deactivate: deactivate() else: activate(self.old_language)
[docs]def get_language(): return _trans.get_language()
[docs]def get_language_bidi(): return _trans.get_language_bidi()
def check_for_language(lang_code): return _trans.check_for_language(lang_code)
[docs]def to_locale(language): return _trans.to_locale(language)
[docs]def get_language_from_request(request, check_path=False): return _trans.get_language_from_request(request, check_path)
def get_language_from_path(path): return _trans.get_language_from_path(path)
[docs]def templatize(src, origin=None): return _trans.templatize(src, origin)
[docs]def deactivate_all(): return _trans.deactivate_all()
def _string_concat(*strings): """ Lazy variant of string concatenation, needed for translations that are constructed from multiple parts. """ return ''.join(force_text(s) for s in strings) string_concat = lazy(_string_concat, six.text_type)
[docs]def get_language_info(lang_code): from django.conf.locale import LANG_INFO try: lang_info = LANG_INFO[lang_code] if 'fallback' in lang_info and 'name' not in lang_info: info = get_language_info(lang_info['fallback'][0]) else: info = lang_info except KeyError: if '-' not in lang_code: raise KeyError("Unknown language code %s." % lang_code) generic_lang_code = lang_code.split('-')[0] try: info = LANG_INFO[generic_lang_code] except KeyError: raise KeyError("Unknown language code %s and %s." % (lang_code, generic_lang_code)) if info: info['name_translated'] = ugettext_lazy(info['name']) return info
trim_whitespace_re = re.compile('\s*\n\s*') def trim_whitespace(s): return trim_whitespace_re.sub(' ', s.strip())
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