Add filter to show post list table `column_cb` even without `edit_post` capability

[coreyw]

Right now the checkbox in the posts list table only shows if the user can edit the post. I am working on a plugin that allows posts to be archived, which means they are not visible publicly, and are no longer editable (until unarchived).

To do this, I have used the map_meta_cap filter to disallow the edit_post capability if the current post_status is archive. This is great because the post in the table no longer has a link to edit or quick edit, and if you use a direct URL to edit the post a message shows to user saying they are not allowed (having a custom message here that says the post is archived would be good, maybe there is already an easy way to do so?).

The problem though, is that the checkbox also is gone in the list table. This does not allow a user to select archived posts and then use the "Unarchive" bulk action.

Currently to get around this, I am looping over debug_backtrace() to check if the current_user_can('edit_post', $id) call is coming from the column_cb function or not and returning the appropriate value. Obviously this is not preferred though.

There may be a better way than simply allowing a filter for the column_cb as well, but hopefully this explains the end goal.

[johnbillion]

Yes please. I've had a need for this too.

https://core.trac.wordpress.org/ticket/51291

https://core.trac.wordpress.org/ticket/51291

[alexstine]

Hello @coreyw

I have linked a PR to this ticket. I've suggested a filter that if set to true, the checkbox will output regardless of capability check. Is this what you were after?

Can I also get your feedback @johnbillion ? Happy to alter or adjust if it's not quite right.

This filter can be added to child theme or plugin.

add_filter( 'bypass_cap_check_on_post_cb', '__return_true' );

Testing welcome.

Thanks.

[johnbillion]

This all looks good @alexstine, just two points:

• The filter needs a better name. Probably something along the lines of show_post_checkbox?
• Let's pass the $post object to the filter for additional context

[alexstine]

@johnbillion Looking better now?

I gave the filter a better name that more closely reflects the area, hopefully it's not too specific. I also added the $post parameter as a 2nd arg.

[johnbillion]

I just had a thought. If the result of the current_user_can check is used as the default value of the filter (instead of being used in place) then the filter can be used both to forcibly enable the checkbox when needed and to forcibly disable it when it isn't needed.

Example:

$show = current_user_can( 'edit_post', $post->ID );

/** ... */
if ( apply_filters( 'wp_list_table_show_post_checkbox', $show, $post ) ) :

@alexstine What do you think?

[alexstine]

@johnbillion Makes sense. current_user_can() returns true/false, so perfect way to use for this situation.

Updated the PR.

[johnbillion]

In 49950:

Posts, Post Types: Introduce the wp_list_table_show_post_checkbox filter which allows the visibility of the bulk edit checkbox on the post list table to be controlled separately from the edit_post capability of the current user.

Props coreyw, alexstine

Fixes #51291

👍 https://core.trac.wordpress.org/changeset/49950

[coreyw]

Thanks @alexstine! And @johnbillion said exactly what I was thinking as well. Looks good to me now.

[audrasjb]

Perhaps it would be nice to mention this change in the Miscellaneous Changes dev note. Tagging this has needs-dev-note to see if it's worth to mention.

[audrasjb]

Dev note published: ​https://make.wordpress.org/core/2021/02/23/miscellaneous-developer-focused-changes-in-wordpress-5-7/