[11.x] Add wildcard directory discovery to the EventServiceProvider

[jared-cannon]

(Most of this post is copied from my Ideas discussion here: #53893 (comment))

Overview

As someone who uses the "Features/" project structure for larger applications, a way to automatically scan each new feature's Listeners directory is a nice, albeit simple, QOL improvement. My suggested change lives in the EventServiceProvider->discoverEvents() function:

Implementation

/**
 * Discover the events and listeners for the application.
 *
 * @return array
 */
public function discoverEvents(): array
{
    return (new Collection($this->discoverEventsWithin()))
        ->flatMap(function ($directory) {
            // Use glob to expand wildcard patterns into directory paths
            return glob($directory, GLOB_ONLYDIR);
        })
        ->reject(function ($directory) {
            return ! is_dir($directory);
        })
        ->reduce(function ($discovered, $directory) {
            return array_merge_recursive(
                $discovered,
                DiscoverEvents::within($directory, $this->eventDiscoveryBasePath())
            );
        }, []);
}

Result

This would allow a user to add the following line to their withEvents() function:

->withEvents(discover: [
    __DIR__.'/../app/Features/*/Listeners',
])

Tests

I could not find an existing test class for the EventServiceProvider, but I can create one if necessary.