12D: Never let a hook throw, whatever the host's code does

[nikolaystrikhar]

What: the plugins_loaded step in Boot\Scheduler, Absorber::render_notices() on all_admin_notices, and Loader::load_all() per sub-plugin all catch Throwable, report with _doing_it_wrong() and abandon that step alone.

Usage:

Absorber::register( [
    'slug'    => 'give-recurring',
    'enabled' => static fn() => give_licence_is_active(), // May throw. The site stays up.
] );

Why this way:

Configuration still throws. register() rejects a bad config array on the spot, at a call in the developer's own stack trace, before anything is hooked. Past that point this library is code on somebody's live site, and a white screen is never the better answer.

The load pass catches per sub-plugin as well. Everything past that catch is host code — the enabled and dependency_check callables, the notice messages, should_load, and the bundled file a require runs top to bottom — and one sub-plugin's throw took the whole site down, front end included, along with every sub-plugin behind it in the registration order.

The reporter takes the step's name and what the site got instead, because the sequence gains a second step at the priority ahead of this one and both have to report the same way.

A re-declaration is the one failure none of this catches, since PHP does not raise it as a Throwable. The guard constant, checked before the require, is what has always prevented that one.

[d4mation]

This is nice! Especially if something like the enabled callback references something that suddenly stops existing this could be a big deal.