PHP notices throws when the attachment parent not exists

[alex-ye]

Some functions throws PHP notices when the attachment parent not exists ( the attachment have a value for a parent post but this post removed by any reason ).

like:
get_attachment_link()
WP_Media_List_Table=>display_rows()

[adamsilverstein]

Replying to alex-ye:

thank you for contributing the bug report _and_ a patch! bravo!

a few notes:

• its best to generate your patches from wp root, this makes applying easier
• you can combine all your file updates into a single patch (same reason)
• watch out for spaces vs. tabs, you might want to turn these on visually in your editor; your patch files had many lines indented with spaces - check the ​php coding standards

24258.diff​​ refactors your patches and is generated from the root, also cleans up spaces vs. tabs issue and a little OCD space cleanup on the get_attachment_link since we were in there anyway (although you don't usually need to clean up old code that isn't to standard)

[SergeyBiryukov]

Thanks for the contribution. This is, however, a duplicate of #22312 and #23154.

[alex-ye]

Thanks for your reply @adamsilverstein you really helps me :)

@SergeyBiryukov mmm, can apply the patch:
​http://core.trac.wordpress.org/attachment/ticket/24258/24258.diff

Insted of
​http://core.trac.wordpress.org/attachment/ticket/23154/23154.diff

I think the @adamsilverstein patch is better.

[SergeyBiryukov]

See the combined patch in #23154.

if ( empty( $post ) ) check in get_attachment_link() from 24258.diff​ probably makes sense, but it should return a string instead of null to be in line with the function's PHPDocs, and should be consistent with other get_*_link() functions, so it's better to address that in a separate ticket.