Fix: Only auto register settings if the plugin the connector references is installed and active.

[jorgefilipecosta]

Summary

• keep connector setting auto-registration unchanged for AI providers
• only auto-register non-AI connector settings when plugin.is_active exists, is callable, and returns true
• add focused PHPUnit coverage for the AI and non-AI registration paths
• The current behavior is wrong if plugin A registers a connector for plugin B we were having a bug where its settings were registered and exposed in REST even if plugin B was not installed and activated. This fixes the issue.

Ticket: https://core.trac.wordpress.org/ticket/65099

Testing

• Verify the connectors page works as before.
• Verify the unit tests pass.

[github-actions]

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[github-actions]

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Props jorgefilipecosta, peterwilsoncc.

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[peterwilsoncc]

As most non-AI connectors will be registered by the plugin itself, this is probably best treated as an optional argument with the default __return_true.

As is, an active plugin registering a connector will need to do something along the lines of the following even though the registration of the connector indicates the plugin is active:

<?php
/**
 * Plugin name: My connector
 */

function my_plugin_register_connector( $registry ) {
  $args = [...];
  $args['plugin']['is_active'] = function() { return function_exists( 'my_plugin_register_connector' ); };

  // etc
}

add_action( 'wp_connectors_init', 'my_plugin_register_connector' );

[jorgefilipecosta]

Good point @peterwilsoncc will make the required updates ☺️

[gziolo]

That's much nicer and more flexible 👍🏻

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 62289
GitHub commit: d141ecb

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.