Language pack is not installed when updating a plugin

[johnbillion]

My plan is to release an update one of my plugins which removes all the bundled language files so that language packs can be used instead. This is so that translations can be updated independently of the plugin.

I'm prevented from doing so because when a user updates a plugin on their site, the corresponding language pack for their selected language does not get installed. This means a user who was previously using my plugin on a (for example) French site will no longer have a French translation for my plugin until they manually visit the Updates screen and update their translations.

When a plugin update is performed, its language pack for the site's selected language should be installed, in addition to it being updated if it's already installed.

[ocean90]

Is this still an issue with trunk? It should be fixed by #34029.

[johnbillion]

Yep, still an issue in trunk.

[ocean90]

As discussed in the linked chat this currently works as expected (in code). Async​ upgrades are disabled if the install is a VCS checkout, see [29694].

To enable updating you can use the following snippet:

<?php
add_filter( 'automatic_updates_is_vcs_checkout', function( $val, $context ) {
    if ( $context === WP_CONTENT_DIR ) {
        return false;
    }

    return $val;
}, 10, 2 );