Narrow return type of do_meta_boxes() (#403)

Author: IanDelMar

functionMap.php

@@ -74,6 +74,7 @@
     'do_action' => ['void', 'hook_name' => 'non-empty-string'],
     'do_action_ref_array' => ['void', 'hook_name' => 'non-empty-string'],
     'do_action_deprecated' => ['void', 'hook_name' => 'non-empty-string'],
+    'do_meta_boxes' => ['int<0, max>'],
     'edit_link' => ['int<0, max>'],
     'edit_term_link' => ['($display is true ? void : string|void)'],
     'get_approved_comments' => ["(\$args is array{count: true}&array ? int : (\$args is array{fields: 'ids'}&array ? array<int, int> : array<int, \WP_Comment>))"],

tests/data/return/do-meta-boxes.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpStubs\WordPress\Core\Tests;
+
+use function do_meta_boxes;
+use function PHPStan\Testing\assertType;
+
+assertType('int<0, max>', do_meta_boxes(Faker::string(), Faker::string(), Faker::mixed()));

wordpress-stubs.php

@@ -89985,6 +89985,7 @@ function _get_plugin_from_callback($callback)
      *                                      Often this is the object that's the focus of the current screen,
      *                                      for example a `WP_Post` or `WP_Comment` object.
      * @return int Number of meta_boxes.
+     * @phpstan-return int<0, max>
      */
     function do_meta_boxes($screen, $context, $data_object)
     {