Improve documentation for is_single()

[danburzo]

Please note that this is just by reading through the source code for get_body_class() and collating that with the docs, so I might be wrong, but would not this code branch be unreachable?

 if (is_single()) { 
    ... 
    if (is_attachment()) {
      // Unreachable?
    } 
 }

In file: https://core.trac.wordpress.org/browser/trunk/src/wp-includes/post-template.php#L570

[ocean90]

Hello @danburzo, welcome to Trac!

I've attached a unit test in 38225.patch​ which shows that it's working. is_single() is true because of this line​.

[danburzo]

Hi @ocean90, thank you for your patience with this!

I'm just starting out reading the source code (which is very well documented, BTW!), there might be something I'm missing. Does that mean that the is_single() function will return true for a single attachment page? In which case this comment needs to be updated?

Is the query for an existing single post?
Works for any post type, except attachments and pages

[ocean90]

#38241 was marked as a duplicate.

[ocean90]

@danburzo Yeah, we should update the docs. Do you want to work on a patch?

[swissspidy]

Just stumbled upon this while working on #18375. It would be great if we could fix it for this release.

[ryankienstra]

Request For Code Review

Hi @ocean90,
Could you please review this patch, which changes the documentation from:
* Works for any post type, except attachments and pages
to:
* Works for any post type, except pages.

As you showed in your comment, is_single() does work for attachment post types. You pointed to how is_single() will be true for attachments.

[swissspidy]

Thanks @ryankienstra! The patch looks good.

[DrewAPicture]

In 39052:

Docs: Update the DocBlock description for WP_Query::is_single() to mention that it works for any post types excluding pages.

Props ryankienstra.
Fixes #38225.

[ocean90]

In 39095:

Query: Add tests for WP_Query::is_single() and get_body_class() with attachments.

See [39052]
See #38225.