weblate/docs/formats/gettext.rst
Michal Čihař 2a2c704285 feat(formats): support removing obsolete entries from PO files
This should avoid confusion by the previous keeping by adding a clear way
to remove obsolete strings.

Fixes #20049
2026-06-15 07:39:14 +02:00

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5.9 KiB
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.. _gettext:
GNU gettext PO (Portable Object)
--------------------------------
.. index::
pair: gettext; file format
pair: PO; file format
Most widely used format for translating libre software.
Contextual info stored in the file is supported by adjusting its
headers or linking to corresponding source files.
.. seealso::
* :doc:`../devel/gettext`
* :doc:`../devel/sphinx`
* `Gettext on Wikipedia <https://en.wikipedia.org/wiki/Gettext>`_
* :doc:`tt:formats/po`
* :ref:`addon-weblate.gettext.authors`
* :ref:`addon-weblate.gettext.configure`
* :ref:`addon-weblate.gettext.customize`
* :ref:`addon-weblate.gettext.linguas`
* :ref:`addon-weblate.gettext.mo`
* :ref:`addon-weblate.gettext.msgmerge`
Showing source string change
++++++++++++++++++++++++++++
Weblate can extract previous source strings from the PO files if present and
show the string difference for strings needing editing based on that. To
include these, :program:`msgmerge` has to be executed with ``--previous`` and
the resulting PO file then contains lines such as:
.. code-block:: po
#, fuzzy
#| msgid "previous-untranslated-string"
msgid "untranslated-string"
msgstr "translated-string"
This is controlled by the ``po_keep_previous`` :ref:`file_format_params`
parameter. It does not affect obsolete entries marked with ``#~``.
Obsolete strings
++++++++++++++++
:program:`msgmerge` keeps strings removed from the POT file as obsolete ``#~``
entries by default. Enable the ``po_remove_obsolete`` :ref:`file_format_params`
parameter to remove obsolete entries when Weblate saves PO files.
PO file header
++++++++++++++
The header of the PO file is automatically maintained by Weblate.
It can be configured to include the ``Language-Team``, ``Last-Translator``,
``X-Generator`` and ``Report-Msgid-Bugs-To`` headers using the :ref:`file_format_params`.
The header comments also can be updated to contain author names using :ref:`addon-weblate.gettext.authors`.
Line wrapping
+++++++++++++
The line wrapping mostly matches GNU gettext behavior. Both the wrapping
algorithm in the GNU gettext and the Unicode data the wrapping is based on
evolve which might cause differences in some corner cases.
The wrapping width can be configured using the ``po_line_wrap`` parameter, see :ref:`file_format_params`.
Generating matching MO files
++++++++++++++++++++++++++++
In case MO files are kept in the repository together with PO files,
:ref:`addon-weblate.gettext.mo` can be used to keep them up-to-date with PO
files.
Updating PO files from the POT file
+++++++++++++++++++++++++++++++++++
:ref:`addon-weblate.gettext.msgmerge` can be used to update PO files from the
POT file, see :ref:`updating-target-files`.
.. _mono_gettext:
Monolingual gettext
+++++++++++++++++++
Some projects decide to use gettext as monolingual formats—they code just the IDs
in their source code and the string then needs to be translated to all languages,
including English. This is supported, though you have to choose
this file format explicitly when importing components into Weblate.
Example files
+++++++++++++
The bilingual gettext PO file typically looks like this:
.. code-block:: po
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "Monday"
msgstr "Pondělí"
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "Tuesday"
msgstr "Úterý"
#: weblate/accounts/avatar.py:163
msgctxt "No known user"
msgid "None"
msgstr "Žádný"
The monolingual gettext PO file typically looks like this:
.. code-block:: po
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "day-monday"
msgstr "Pondělí"
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "day-tuesday"
msgstr "Úterý"
#: weblate/accounts/avatar.py:163
msgid "none-user"
msgstr "Žádný"
While the base language file will be:
.. code-block:: po
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "day-monday"
msgstr "Monday"
#: weblate/media/js/bootstrap-datepicker.js:1421
msgid "day-tuesday"
msgstr "Tuesday"
#: weblate/accounts/avatar.py:163
msgid "none-user"
msgstr "None"
.. include:: /snippets/format-features/po-mono-features.rst
.. include:: /snippets/format-features/po-features.rst
Weblate configuration
+++++++++++++++++++++
+-------------------------------------------------------------------+
| Typical Weblate :ref:`component` for bilingual gettext |
+================================+==================================+
| File mask | ``po/*.po`` |
+--------------------------------+----------------------------------+
| Monolingual base language file | `Empty` |
+--------------------------------+----------------------------------+
| Template for new translations | ``po/messages.pot`` |
+--------------------------------+----------------------------------+
| File format | `Gettext PO file` |
+--------------------------------+----------------------------------+
+-------------------------------------------------------------------+
| Typical Weblate :ref:`component` for monolingual gettext |
+================================+==================================+
| File mask | ``po/*.po`` |
+--------------------------------+----------------------------------+
| Monolingual base language file | ``po/en.po`` |
+--------------------------------+----------------------------------+
| Template for new translations | ``po/messages.pot`` |
+--------------------------------+----------------------------------+
| File format | `Gettext PO file (monolingual)` |
+--------------------------------+----------------------------------+
File format parameters
++++++++++++++++++++++
:ref:`file_format_params` with the pattern `po_*` can be used to configure the behavior of the gettext format.