customize-changesets-admin-ui.php

<?php
/**
 * Plugin Name: Customize Changesets Admin UI
 * Description: Enable revisions for customize changeset posts and enable admin screens.
 * Author: Weston Ruter, XWP
 *
 * @package Customize_Changesets_Admin_UI
 */

namespace Customize_Changesets_Admin_UI;

const POST_TYPE = 'customize_changeset';

/**
 * Extend post type object.
 */
function extend_post_type_object() {
	$post_type_obj = get_post_type_object( 'customize_changeset' );
	add_post_type_support( POST_TYPE, 'revisions' );
	$post_type_obj->show_ui = true;
	$post_type_obj->show_in_menu = true;
	$post_type_obj->menu_position = 100;
	$post_type_obj->_edit_link = 'post.php?post=%d'; /* internal use only. don't use this when registering your own post type. */
}
add_action( 'init', __NAMESPACE__ . '\extend_post_type_object', 100 );

/**
 * Add meta box.
 */
function add_meta_box() {
	$id = 'customize_changeset_data';
	$title = __( 'Changeset Data' );
	$callback = __NAMESPACE__ . '\render_meta_box';
	$screen = POST_TYPE;
	$context = 'normal';
	$priority = 'high';
	\add_meta_box( $id, $title, $callback, $screen, $context, $priority );
}
add_action( 'add_meta_boxes', __NAMESPACE__ . '\add_meta_box', 100 );

/**
 * Render meta box.
 *
 * @param int $post_id Post id.
 */
function render_meta_box( $post_id ) {
	echo '<pre>';
	echo esc_html( wp_json_encode( json_decode( get_post( $post_id )->post_content, true ), JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES ) );
	echo '</pre>';
}

/**
 * Re-map customize meta cap to edit_theme_options primitive cap.
 *
 * @param array  $caps All caps.
 * @param string $cap  Requested cap.
 *
 * @return array All caps.
 */
function remap_customize_meta_cap( $caps, $cap ) {
	$post_type_obj = get_post_type_object( POST_TYPE );
	if ( isset( $post_type_obj->cap->$cap ) && 'customize' === $post_type_obj->cap->$cap ) {
		foreach ( $caps as &$required_cap ) {
			if ( 'customize' === $required_cap ) {
				$required_cap = 'edit_theme_options';
			}
		}
	}
	return $caps;
}
add_filter( 'map_meta_cap', __NAMESPACE__ . '\remap_customize_meta_cap', 5, 4 );

/**
 * Add admin menu item.
 */
function add_admin_menu_item() {
	$post_type_object = get_post_type_object( POST_TYPE );
	$capability = $post_type_object->cap->edit_posts;
	$page_title = $post_type_object->labels->name;
	$menu_title = $post_type_object->labels->name;
	$menu_slug = 'edit.php?post_type=customize_changeset';
	add_theme_page( $page_title, $menu_title, $capability, $menu_slug );
}
add_action( 'admin_menu', __NAMESPACE__ . '\add_admin_menu_item' );

This is not working anymore. map_meta_cap doesnt find the req variable.