Documentation for add_meta_boxes hook specifies incomplete parameter types

[jbeales]

Issue Description

The documentation page for the add_meta_boxes hook says that the second parameter is a WP_Post type, but it is sometimes a WP_Comment, and is sometimes a stdClass which leads to fatal errors if developers hook a function to add_meta_boxes with typed parameters.

A WP_Comment is passed to the hook in the Edit Comment screen, for example: /wp-admin/comment.php?action=editcomment&c=12332

A `stcClass is passed to the hook in the Edit lInk screen, for example: /wp-admin/link.php?action=edit&link_id=5

The possibility that the second parameter could be a WP_Comment was reported and fixed in Trac 6 years ago, but maybe the fix there never got migrated to developer.wordpress.org. I haven't found any reference to the possibility of the parameter being a stdClass.

URL of the Page with the Issue

https://developer.wordpress.org/reference/hooks/add_meta_boxes/

Section of Page with the issue

The function definition at the top of the page and the parameter descriptions include the erroneous WP_Post type.

Why is this a problem?

PHP is moving more towards typed function definitions, and if developers try to hook a function to add_meta_boxes that has a WP_Post type for the second argument, (like I did!), they get a fatal error.

Suggested Fix

Specify that the second argument may be a WP_Post, WP_Comment, or stcClass.

[github-actions[bot]]

Heads up @WordPress/docs-issues-coordinators, we have a new issue open. Time to use 'em labels.