I think this is ready for a quick look @acobster or @gchtr. There is one failing test related to PostQuery being used in Timber::context(); ...

1) TestTimberContext::testPostsContextSimple
Unexpected deprecated notice for Timber\PostQuery::get_posts()
Failed asserting that an array is empty.

/srv/www/wordpress-trunk/public_html/tests/phpunit/includes/abstract-testcase.php:494
/srv/www/timber/tests/Timber_UnitTestCase.php:17
/srv/www/wordpress-trunk/public_html/tests/phpunit/includes/abstract-testcase.php:506

... but this isn't connected to the code here and I believe is addressed in #2316

@jarednova looks good to me (and you're correct about that PostQuery usage), although I was kinda planning on deleting this class (among others) as part of THE PURGE. 🔪 It's not documented AFAIK and will break expectations set in the docs if it's used. If you see a good reason to keep it around as deprecated, I suppose I can stay my bloodlust.

@acobster cool! let's take up the question of deprecation vs. blood over on #2323