manipulating post order in Timber $context['posts'] object - timber

Question

I'm trying to ensure the first two posts in my {{ posts }} object have thumbnails while the rest of the posts continue to order by most recently published first. I am trying to create a filter like so to accomplish this:
Filter definition in PHP:
function posts_with_thumbs_first_filter( $posts, $num_top_posts = 2 ){
// find first posts with thumbnails in them to decide what posts need to be reordered to first position in the array
$first_posts_with_thumbs = array();
foreach ($posts as $key => $post) {
if ($post->thumbnail) {
$first_posts_with_thumbs[] = $key;
if (count($first_posts_with_thumbs) == $num_top_posts) { break; }
}
}
...manipulate order of posts here...
return $posts;
}
Use of filter in Twig:
{% for post in posts|posts_with_thumbs_first %}
...regular post output here, only with posts now reordered...
{% endfor %}
But it looks like manipulating the order of the posts is tricky because it's not a standard array, it's a Timber\PostQuery object with private iterators and methods inside that control the posts data. I can't use PHP's array functions like array_slice, array_splice, etc. because posts is not an array, it's an object.
Is there a solid way to manipulate the order of the posts?

Answer 1

Here's one way to do it: convert the posts object to an array to enable usage of PHP's array manipulation functions.
function posts_with_thumbs_first_filter( $posts, $num_top_posts = 2 ){
$posts = (array) $posts; // convert posts object to array to use PHP's array manipulating functions
$first_posts_with_thumbs = array();
foreach ($posts as $key => $post) {
if ($post->thumbnail) {
$first_posts_with_thumbs[] = $key;
if (count($first_posts_with_thumbs) === $num_top_posts) { break; }
}
}
$posts_to_move_to_top = array();
for ($i = count($first_posts_with_thumbs) - 1; $i >= 0; $i--){
$posts[$first_posts_with_thumbs[$i]]->moved = true;
$posts_to_move_to_top[] = array_splice($posts, ($first_posts_with_thumbs[$i]), 1); // extract post from posts array
}
foreach ($posts_to_move_to_top as $post) { // put back into posts at beginning
array_unshift($posts, $post[0]);
}
return $posts;
}