`get_post_status()` is can be incorrect for attachments.

[peterwilsoncc]

get_post_status() can return an incorrect status for attachments in the following circumstances:

• Attachment with inherit status from future post: returns 'publish', ought to be 'future'
• Attachment with status draft and no parent: returns 'publish', ought to be 'draft' (can't be done in admin, only via code)
• Attachment with inherit status and post_parent set to nonexistent post: returns false, ought to be 'publish'.

I've attached unit tests to demonstrate.

https://core.trac.wordpress.org/ticket/52326

[peterwilsoncc]

In ​PR #881:

• Unit tests
• A valid attachment ID can no longer return false as the status
• attachment with inherit status always inherits parent posts status unless trashed (need to confirm this is correct)
• trashed posts return the status immediately prior to the post been trashed using the meta data
• if the meta data is not set/the parent post does not exist the attachment defaults to publish.
• attachments are now passed through the get_post_status filter, they bypassed it before.

[peterwilsoncc]

Putting this on the milestone as it's going to be helpful for #5272.

Will need a comment in the general dev note (rather than a dedicated one) that the get_post_status filter now runs for attachments too.

trash changes were introduced in 4.0.0 but various other bugs have been around since the function was introduced in 2.2.0.

[peterwilsoncc]

In 49985:

Media: Ensure get_post_status() returns correct result for attachments.

Prevent get_post_status() returning false for attachments if the parent post has been deleted. The returned attachment post status is now passed through the get_post_status filter.

Add tests for get_post_status().

Props peterwilsoncc, timothyblynjacobs for review.
Fixes #52326.

[SergeyBiryukov]

// Attachment permitted statuses: 'inherit', , see wp_insert_post().

Did this list mean to include something other than inherit? I assume publish, but wanted to double-check :)

[peterwilsoncc]

@SergeyBiryukov Failed cut and paste when I moved it to the elseif below. Fix incoming.

[peterwilsoncc]

In 49986:

Media: Ensure get_post_status() does not contain half a comment.

Removes a misplaced comment, follow up to [49985].

Props SergeyBiryukov.
Fixes #52326.

[joyously]

A valid attachment ID can no longer return false as the status
attachment with inherit status always inherits parent posts status unless trashed (need to confirm this is correct)
if the meta data is not set/the parent post does not exist the attachment defaults to publish

publish seems like the wrong default for an attachment with no parent. Where is it published? I would suggest draft in this case.

Is this marked for a dev note? There could be plugins checking for false.

[peterwilsoncc]

Replying to joyously:

publish seems like the wrong default for an attachment with no parent. Where is it published? I would suggest draft in this case.

For trashed parents, attachments have worked like this for a long time (at least as far back as 4.4.0). An attachment uploaded with one post as the parent may be published on another and WP Core offers no protections against using files in the uploads folder.

Is this marked for a dev note? There could be plugins checking for false.

Yes, this is marked for a dev note.

[audrasjb]

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