Automattic
Bug: Quick Edit in User Groups PHP Error
Expected/Desired Behavior
No PHP Errors when using Quick Edit
Actual Behavior
PHP Error:
[07-Jun-2021 17:34:31 UTC] PHP Warning: Undefined array key "hook_suffix" in /wp-admin/includes/class-wp-screen.php on line 223
In the console:
component: "Plugin: Edit-Flow"
file: "wp-admin/includes/class-wp-screen.php"
key: "d5841370c9175d9d14dff829bd2b4b69"
line: 224
message: "Undefined array key \"hook_suffix\""
stack: Array(6)
0: "WP_Screen::get()"
1: "convert_to_screen()"
2: "WP_List_Table->__construct()"
3: "EF_Usergroups_List_Table->__construct()"
4: "EF_User_Groups->handle_ajax_inline_save_usergroup()"
5: "do_action('wp_ajax_inline_save_usergroup')"
length: 6
__proto__: Array(0)
type: "warning"
__proto__: Object
Steps to Reproduce the Problem
- Go to Edit Flow -> User Groups
- Click Quick Edit
- Make a change
- Click "Update User Group"
(Optional) Additional notes
I think the problem is here: https://github.com/Automattic/Edit-Flow/blob/master/modules/user-groups/user-groups.php#L1097-L1103
The __construct() should have screen because the method WordPress uses to determine this doesn't run when an AJAX call is made.
As mentioned in https://github.com/Automattic/Edit-Flow/pull/666#pullrequestreview-681493522, this is a bug in core WP https://core.trac.wordpress.org/ticket/49089
Replicate this issue in the core
- Add this file under wp-content/mu-plugins https://gist.github.com/htdat/06d77ea326d53cb1ae1e6b68c96aa0c3
- Visit wp-admin/edit.php
- Try to edit a post with "Quick Edit" to trigger the ajax action
- Check PHP error log (debug.log)
Error with track trace:
[12-Jul-2021 04:28:47 UTC] PHP Notice: Undefined index: hook_suffix in /var/www/html/wp-admin/includes/class-wp-screen.php on line 223 [12-Jul-2021 04:28:47 UTC] PHP Stack trace: [12-Jul-2021 04:28:47 UTC] PHP 1. {main}() /var/www/html/wp-admin/admin-ajax.php:0 [12-Jul-2021 04:28:47 UTC] PHP 2. do_action() /var/www/html/wp-admin/admin-ajax.php:187 [12-Jul-2021 04:28:47 UTC] PHP 3. WP_Hook->do_action() /var/www/html/wp-includes/plugin.php:484 [12-Jul-2021 04:28:47 UTC] PHP 4. WP_Hook->apply_filters() /var/www/html/wp-includes/class-wp-hook.php:316 [12-Jul-2021 04:28:47 UTC] PHP 5. {closure:/var/www/html/wp-content/mu-plugins/trac-49089.php:11-24}() /var/www/html/wp-includes/class-wp-hook.php:292 [12-Jul-2021 04:28:47 UTC] PHP 6. WP_List_Table->__construct() /var/www/html/wp-content/mu-plugins/trac-49089.php:14 [12-Jul-2021 04:28:47 UTC] PHP 7. convert_to_screen() /var/www/html/wp-admin/includes/class-wp-list-table.php:149 [12-Jul-2021 04:28:47 UTC] PHP 8. WP_Screen::get() /var/www/html/wp-admin/includes/template.php:2571
Root cause
The error happens around this line http://github.com/WordPress/WordPress/blob/9f91305af2bd18c914096cc5e5cc1d6882163200/wp-admin/includes/class-wp-screen.php#L223-L223
$id = $GLOBALS['hook_suffix'];
admin-ajax.php requests do not load file wp-admin/admin.php, which is loaded when admins browse wp-admin pages.
Then global $hook_suffix is not added and defined, hence, the PHP error Undefined index: hook_suffix happens.
- http://github.com/WordPress/WordPress/blob/9f91305af2bd18c914096cc5e5cc1d6882163200/wp-admin/admin.php#L203-L210
A side note here: I searched hook_suffix and $hook_suffix across WordPress core and found out that this global $hook_suffix var is set up in file wp-admin/admin.php.
Solution
I think the ultimate solution here is to change the way we handle $GLOBALS['hook_suffix']. Here is my proposal :D
Index: wp-admin/includes/class-wp-screen.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/wp-admin/includes/class-wp-screen.php b/wp-admin/includes/class-wp-screen.php
--- a/wp-admin/includes/class-wp-screen.php (date 1623657694433)
+++ b/wp-admin/includes/class-wp-screen.php (date 1623657694433)
@@ -220,7 +220,10 @@
if ( $hook_name ) {
$id = $hook_name;
} else {
- $id = $GLOBALS['hook_suffix'];
+ // AJAX requests does not load wp-admin/admin.php, which sets value for global $hook_suffix
+ $id = wp_doing_ajax()
+ ? 'wp_ajax_' . esc_attr( $_REQUEST['action'] )
+ : $GLOBALS['hook_suffix'];
}
// For those pesky meta boxes.
What do you think, @mikeyarce? If you have time, I would like to see your thought too, @nielslange.
@mikeyarce pointed out a great point: This notice error will be converted into a warning in PHP8 and that might cause a bigger headache. Ref:
- https://stackoverflow.com/a/66125363
- https://www.php.net/manual/en/migration80.incompatible.php:
A number of notices have been converted into warnings: ... Attempting to read an undefined array key.
FYI. Submitted a PR for this core issue:
- https://core.trac.wordpress.org/ticket/49089#comment:3
- https://github.com/WordPress/wordpress-develop/pull/1490