[ogorzalka]

What

A data file, resources/i18n.php, lists the constructor parameters of the attributes that hold text shown to a person (labels, titles, descriptions, singular and plural names…), and composer.json announces it under extra.pollora.i18n.

return [
    PostType::class => ['singular', 'plural'],
    AdminCol::class => ['title'],
    // …
];

It is plain data: this package does not depend on any translation package, and a tool such as pollora/i18n can read the file to know which strings to extract and translate.

Drift guard

tests/Unit/I18nDeclarationTest.php walks every attribute class of src/ (file system and reflection, no hard-coded list) and requires each string or array constructor parameter to be either in resources/i18n.php or in an explicit "technical" list of the test (slugs, keys, hooks, capabilities, formats, callbacks…). A parameter that is in neither makes the test fail and says what to do, so a new text parameter cannot be added without deciding whether it is translated. It also checks that no parameter is classified twice, that no entry points at a parameter that no longer exists, that composer.json declares the file, and that .gitattributes does not exclude resources/.

Choices worth a look

• Translatable: Ability::label and description, Meta::label, description and group, PostType\FeaturedImage::value, Role::label.
• Not translatable: the array parameters that mix text and technical values (AdminCols, AdminFilters, Template, Meta::hints): the text inside them is marked where it is written, with new Translatable('…') from pollora/i18n, rather than declared here. Taxonomy\DefaultTerm (stored in the database at creation) and WpCli\Synopsis (WP-CLI does not translate them).

No dependency is added and no signature changes.