Re-setup the translation system about bileto HOT 4 CLOSED

I'm bringing this subject back to 0.2-dev and extending it.

I realize we can't translate strings based on a number. The old way was to use transchoice:

{{ '{0} No users|{1} 1 user|]1,Inf[ %count% users' | trans(users|length) }}

But transchoice no longer exists since Symfony 5! Two solutions:

1. Use conditions in the template:

{% if users|length == 0 %}
    {{ 'No users' | trans }}
{% elseif users|length == 1 %}
    {{ '1 user' | trans }}
{% else %}
    {{ '%count% users' | trans({ '%choice%': users|length }) }}
{% endif %}

2. use ICU format

The first solution is definitely not an option on the long term and makes things complicated.
The second solution looks better (ICU is the current supported format), but I had troubles the last time I tried.
Hopefully problems have been fixed since then.

The migration to ICU format should be done in four steps:

• migrate files to +intl-icu.yaml
• adapt current strings to use ICU format
• change translation keys to use a keyword format (e.g. users.number) (ICU format is more verbose)
• adapt the make i18n-extract script?

from bileto.

References:

• symfony/symfony-docs#11002 (comment)
• https://symfony.com/doc/current/translation.html
• https://symfony.com/doc/current/reference/formats/message_format.html

from bileto.

I just migrated the translations to ICU format. It was painful because I wanted to use a keyword format for keys. At least it's done for the messages domain.

The validators domain is not fully migrated since the {{ value }} variables have to be renamed to { value } and there are a lot of strings. Instead, I'd like to remove all the unused keys (generated by Symfony) and only keep the ones that I explicitly use in Bileto. Btw, it seems that TranslatableMessage is optional for entity assertions messages (see https://symfony.com/doc/current/validation/translations.html), BUT the extract command was only able to find some keys when I tried 🤷

It would be the occasion to improve the error messages to be more assertive and explain what have to be done to fix the errors (e.g. "Choose a different email address since { value } is already used.")

from bileto.

I think I found a solution:

1. change the domain of the actual "validators" and "security" (only https://github.com/Probesys/bileto/blob/main/src/Controller/BaseController.php#L33 is concerned) domains to "errors" (but keep the files for the default translations of Symfony)
2. stop extracting messages for the "validators" and "security" domains
3. extract the "errors" domain as it is done for "messages"

The only potential problem is that I don't know if the --domain argument of the extract command can take several domains. Otherwise, I'll have to extract "errors" and "messages" with two different commands :/

from bileto.