Media Grid View bulk deletion not respecting individual delete capabilities

[skaeser]

The bulk delete functionality of the Media Grid View does not check whether the deleted items where actually deleted or not, it simply assumes they where and removes them from the list. When using individual delete capabilities on media items this results in items being removed from the list while they have not actually been deleted.

Steps to reproduce this issue:

Register a custom filter for "user_has_cap" and set the "delete_posts" and "delete_post" capability for a specific attachment to "false":

function test_individual_media_delete_capability($allcaps, $caps, $args) {
  if ( count( $args ) > 2 && ( in_array( 'delete_post', $caps ) || in_array( 'delete_posts', $caps ) ) ) {
    $post = get_post( $args[2] );
    if ( $post->ID == [EXISTING ATTACHMENT ID] && $post->post_type ==
'attachment' ) {
      $allcaps['delete_post'] = false;
      $allcaps['delete_posts'] = false;
    }
  }
  return $allcaps;
}

add_filter("user_has_cap", test_individual_media_delete_capability, 100, 3);

Now go to the Media Library (Grid View) and click "Bulk Select".

Select the attachment having the ID used in the function above and press "Delete Selected". The attachment gets removed from the list.

Reload the page and the attachment is back in place.

As the AJAX call to "admin-ajax.php" (action: delete-post) properly returns a "-1" if deletion of the post fails, the fix should only involve JavaScript. Unfortunately I am not familiar enough with the JavaScript architecture in place to create a proper fix.

[wonderboymusic]

[29755] missed the ticket.

[tlovett1]

Not able to reproduce in r30026.

[johnbillion]

@tlovett1: This has been fixed in trunk but the ticket remains open because we'll be adding this to the 4.0.1 release.

[nacin]

In 30409:

Media Grid: Don't attempt to delete an attachment that can't be deleted.

Merges [29755] to the 4.0 branch.

props wonderboymusic.
fixes #29597.