Debugging Translations

.. versionadded:: 2.5

The ``translation:debug`` command was introduced in Symfony 2.5.

When maintaining a bundle, you may use or remove the usage of a translation

message without updating all message catalogues. The ``translation:debug``

command helps you to find these missing or unused translation messages for a

given locale. It shows you a table with the result when translating the

message in the given locale and the result when the fallback would be used.

On top of that, it also shows you when the translation is the same as the

fallback translation (this could indicate that the message was not correctly

translated).

Thanks to the messages extractors, the command will detect the translation

tag or filter usages in Twig templates:

.. code-block:: jinja

It will also detect the following translator usages in PHP templates:

.. code-block:: php

.. caution::

The extractors are not able to inspect the messages translated outside templates which means

that translator usages in form labels or inside your controllers won't be detected.

Dynamic translations involving variables or expressions are not detected in templates,

which means this example won't be analyzed:

.. code-block:: jinja

Suppose your application's default_locale is ``fr`` and you have configured ``en`` as the fallback locale

(see :ref:`book-translation-configuration` and :ref:`book-translation-fallback` for how to configure these).

And suppose you've already setup some translations for the ``fr`` locale inside an AcmeDemoBundle:

.. configuration-block::

.. code-block:: xml

.. code-block:: php

.. code-block:: yaml

and for the ``en`` locale:

.. configuration-block::

.. code-block:: xml

.. code-block:: php

.. code-block:: yaml

To inspect all messages in the ``fr`` locale for the AcmeDemoBundle, run:

.. code-block:: bash

You will get this output:

.. image:: /images/book/translation/debug_1.png

:align: center

It indicates that the message ``Symfony2 is great`` is unused because it is translated,

but you haven't used it anywhere yet.

Now, if you translate the message in one of your templates, you will get this output:

.. image:: /images/book/translation/debug_2.png

:align: center

The state is empty which means the message is translated in the ``fr`` locale and used in one or more templates.

If you delete the message ``Symfony2 is great`` from your translation file for the ``fr`` locale

and run the command, you will get:

.. image:: /images/book/translation/debug_3.png

:align: center

The state indicates the message is missing because it is not translated in the ``fr`` locale

but it is still used in the template.

Moreover, the message in the ``fr`` locale equals to the message in the ``en`` locale.

This is a special case because the untranslated message id equals its translation in the ``en`` locale.

If you copy the content of the translation file in the ``en`` locale, to the translation file

in the ``fr`` locale and run the command, you will get:

.. image:: /images/book/translation/debug_4.png

:align: center

You can see that the translations of the message are identical in the ``fr`` and ``en`` locales

which means this message was probably copied from French to English and maybe you forgot to translate it.

By default all domains are inspected, but it is possible to specify a single domain:

.. code-block:: bash

When bundles have a lot of messages, it is useful to display only the unused

or only the missing messages, by using the ``--only-unused`` or ``--only-missing`` switches:

.. code-block:: bash