[wp-hackers] Filters on get_posts()

[John Blackbourn]

These days I find myself using multiple additional loops on the
majority of sites I build, as I'm sure many people on this list do.
The problem I'm now running into is the all-or-nothing filtering on
the get_posts() function which is used for additional loops.

By default, get_posts() sets the 'suppress_filters' parameter to
'true' meaning all the filters such as 'posts_where', 'posts_join' and
'posts_request' are not applied. This is desired behaviour, because
plugins that use these filters often filter the query based on the
global conditionals and the main WordPress query. If these filters
were applied to additional loops then we'd probably get unexpected
results.

So the problem is that with 'suppress_filters' set to 'true', we're
left with absolutely no filters on get_posts(). (Well, we have the
'posts_search' filter that affects the query if we're doing a search,
but that's it.)

I'd like to use get_posts() to get posts for my additional loop, but
I'd also like to filter the query string so I can join an additional
table (specifically, the translations lookup table from WPML [1] in
order to fetch translated posts). The only filter I can use is the
all-encompassing 'query' filter which applied to every single database
query.

In order to get around this I'm currently adding a filter to 'query'
before calling get_posts() and removing the filter immediately
afterwards. This is not good for my OCD. I also contemplated fetching
the posts and then fetching the translated posts in a second query,
but this isn't ideal either (especially as WPML is a bit heavy on
queries anyway).

Is there an argument here for adding a filter to the get_posts() query
string that's applied regardless of the 'suppress_filters' argument?
Is that just asking for trouble from plugins that end up incorrectly
using this filter? Or is there a better way of going about this?

Regards,
John

P.S. I'm aware of the 'pre_get_posts' action that affects the query
object in this function, but this only lets you control the query
arguments used to build the query string, not the query string itself.

[1] http://wpml.org/