makemessages doesn't detect the context of {% trans %} strings with a filter

[Alexandre Pocquet]

The following:

{% trans 'inactive'|upper context 'plural' %}

Is (incorrectly) extracted as:

msgid "inactive"
msgstr ""

Whereas the following:

{% trans 'inactive' context 'plural' %}

Is (correctly) extracted as:

msgctxt "plural"
msgid "inactive"
msgstr ""

Translating the former has no effect on the template rendering, as it lacks the context.
Translating the latter makes the translation to be correctly rendered, both without the filter, and with the filter if added after makemessages was called.

I think this is a bug with the makemessages command.

Environnement:
Linux Mint Debian Edition
CPython 3.4.2
Django 1.8.3
GNU gettext 0.19.3

Command used:
./manage.py makemessages -v 1 -l fr
./manage.py compilemessages

[Tim Graham]

If this cannot be made to work for some reason, documenting the restriction may be helpful.

[Alexandre Pocquet]

I think the problem may come from the inline_re definition in django.utils.translation.trans_real . It it used by the templatize function, which it itself called from the commandline handler.

Current:

inline_re = re.compile(r"""^\s*trans\s+((?:"[^"]*?")|(?:'[^']*?'))(\s+.*context\s+((?:"[^"]*?")|(?:'[^']*?')))?\s*""")

Possible correction:

inline_re = re.compile(r"""^\s*trans\s+((?:"[^"]*?")|(?:'[^']*?'))(?:\s*\|\s*[^\s:]+(?::(?:[^\s'":]+|(?:"[^"]*?")|(?:'[^']*?')))?)*(\s+.*context\s+((?:"[^"]*?")|(?:'[^']*?')))?\s*""")

The (?:\s*\|\s*[^\s]+(?::(?:\s+|(?:"[^"]*?")|(?:'[^']*?'))?))* regex should catch and throw away any filter. I may be wrong, I don't know the precise syntax of a filter name.
The first part is quite simple and matches a | followed by a filter name. The second part (starting with ?::) is more complex because it must match filter arguments, including string literals.

Test ​here.

[Tim Graham]

​PR (but has a test failure).

[Tim Graham]

Left some comments for improvement on the pull request.

[Tim Graham <timograham@…>]

In e7b7f946:

Fixed #25297 -- Allowed makemessages to work with {% trans %} tags that use template filters.