Trac 57662 test plugin -- enables custom WordPress package update

fake-wordpress-update.php

<?php
/**
 * Plugin Name: Fake WordPress Update
 * Description: Filters the value of <code>site_transient_update_core</code> to allow a custom install package.
 * Author:      WordPress Core Contributors
 * Author URI:  https://make.wordpress.org/core
 * License:     GPLv2 or later
 * Version:     1.0.0
 *
 * Adapted from https://gist.githubusercontent.com/hellofromtonya/bb0aa2d4b2311c8b40fa5ae8ada4dc19
 */

add_filter(
    'site_transient_update_core',
    function ( $value ) {
        if ( ! isset( $value->updates ) ) {
            return $value;
        }
        
        $fake_update_location = trailingslashit( get_bloginfo( 'url' ) ) . 'wordpress-custom.zip';
        $fake_update          = (object) array(
            'response' => 'upgrade',
            'download' => $fake_update_location,
            'locale' => 'en_US',
            'packages' => 
            (object) array(
                'full' => $fake_update_location,
                'no_content' => $fake_update_location,
                'new_bundled' => $fake_update_location,
                'partial' => '',
                'rollback' => '',
            ),
            'current' => '6.3.0-custom',
            'version' => '6.3.0-custom',
            'php_version' => '5.6.20',
            'mysql_version' => '5.0',
            'new_bundled' => '6.3',
            'partial_version' => '',
            'version_checked' => '',
        );

        array_unshift( $value->updates, $fake_update );

        return $value;
    }
);

To test the patch for Trac 57662 using this plugin:

1. First follow the setup Steps 1-7 outlined here: https://core.trac.wordpress.org/ticket/57662#comment:3
2. Refer to the following commands to prepare a custom package ZIP that contains the patch (this is instead of using the WordPress Beta Tester plugin to upgrade):

# AFTER COMPLETING TEST STEP 7, CONTINUE HERE:

# PREPARE CUSTOM PACKAGE ZIP
# download 6.2-beta1 (or update to a newer zip if needed)
curl -O https://downloads.wordpress.org/release/wordpress-6.2-beta1.zip
unzip wordpress-6.2-beta1.zip
# download patch file for PR 4029 (for update-core.php)
cd wordpress
curl -O https://patch-diff.githubusercontent.com/raw/WordPress/wordpress-develop/pull/4029.diff
# apply patch
patch wp-admin/includes/update-core.php 4029.diff
# should show: patching file wp-admin/includes/update-core.php
# now zip the customized package
cd ..
zip -r wordpress-custom.zip wordpress
# change directory to test site root, e.g.
cd ~/Sites/wp-install-test/
# copy custom package into the site root, e.g.
cp ~/Downloads/wordpress-custom.zip .
# NOTE: Custom ZIP file must be accessible at:
#   http://<your-test.site>/wordpress-custom.zip

# PREPARE CUSTOM UPDATE PLUGIN
# install custom wordpress update plugin
curl https://gist.githubusercontent.com/ironprogrammer/1aaff6f60b263c1842e3584365729ffc/raw/782e3683a88f560c665313c8365c807b6093847b/fake-wordpress-update.php -o wp-content/plugins/fake-wordpress-update.php
# enable the plugin
wp plugin activate fake-wordpress-update

# NOW PROCEED WITH TEST STEP 10

3. Now continue with the original test instructions at Step 10.

Once testing is complete, deactivate the plugin to prevent the fake update nag.

On 2023-06-27 updated plugin to fake version 6.3.0-custom for Trac 58206 testing.