WP_Comment_Query with WP_Meta_Query integration

[nikolov.tmw]

Basically the title says it all. What I'd like to see in WordPress is an implementation of the WP_Meta_Query that was intorduced in 3.2 for the comments query as well as ordering by meta values.

Basically if those features are implemented, developers will have greater flexibility about comments - the first things that come to mind are rating system(I know there should be a plugin out there for that already), separating comments by some parameter(let's say age/sex/country/etc, if there is some kind of sociological study) and many more.

I stumbled upon this quite recently when I was making an extension for qTranslata and I had to get comments by specific meta value - I had to either write custom MySQL(at which I'm not really good), or implement the meta query.

I'm attaching the diff file that I made(I've tested that with 3.4) for wp-includes/comments.php

Patch for integrating meta_query and meta_value ordering for comments queries

Looks good on first glance.

Needs a final review.

Unit tests can go here: ​http://unit-tests.trac.wordpress.org/browser/trunk/tests/comment.php#L8

Replying to ryan:

Unit tests can go here: ​http://unit-tests.trac.wordpress.org/browser/trunk/tests/comment.php#L8

Which I just moved to ​http://unit-tests.trac.wordpress.org/browser/trunk/tests/comment/query.php

Refresh

The last assertion in those tests fails. The same comment occurs twice in the results.

In WP_Query, we have this for dealing with duplicates:

if ( !empty( $this->tax_query->queries ) || !empty( $this->meta_query->queries ) ) {
	$groupby = "{$wpdb->posts}.ID";
}

Quick group by patch

In [22074]:

Support meta queries in WP_Comment_Query.

Props nikolov.tmw
fixes #21003

Replying to ryan:

In [22074]:

Support meta queries in WP_Comment_Query.

Props nikolov.tmw
fixes #21003

return $cache was left commented out on line 260.

In [22079]:

Remove debug cruft. Props duck_. fixes #21003

Follow-up: #23208