Tell SearchWP to give more weight to WP_Posts with more comments

searchwp-customizations.php

<?php

// Add relevance weight based on number of comments.
add_filter( 'searchwp\query\mods', function( $mods ) {
	global $wpdb;

	// Multiply the number of comments by this multiplier.
	$comment_count_multiplier = 1;

	$mod = new \SearchWP\Mod();
	$mod->set_local_table( $wpdb->posts );
	$mod->on( 'ID', [ 'column' => 'id' ] );

	$mod->weight( function( $runtime_mod ) use ( $comment_count_multiplier ) {
		$local_alias = $runtime_mod->get_local_table_alias();

		return "(IF({$local_alias}.comment_count > 0,
			(CASE
				WHEN (LOG({$local_alias}.comment_count) > 6) THEN 6
				WHEN (LOG({$local_alias}.comment_count) < 1) THEN 1
				ELSE ROUND(LOG({$local_alias}.comment_count))
			END),0))";
	} );

	$mods[] = $mod;

	return $mods;
} );