_set_preview( WP_Post $post ): WP_Post|false

869function _set_preview( $post ) {870	if ( ! is_object( $post ) ) {871		return $post;872	}873 874	$preview = wp_get_post_autosave( $post->ID );875 876	if ( is_object( $preview ) ) {877		$preview = sanitize_post( $preview );878 879		$post->post_content = $preview->post_content;880		$post->post_title   = $preview->post_title;881		$post->post_excerpt = $preview->post_excerpt;882	}883 884	add_filter( 'get_the_terms', '_wp_preview_terms_filter', 10, 3 );885	add_filter( 'get_post_metadata', '_wp_preview_post_thumbnail_filter', 10, 3 );886	add_filter( 'get_post_metadata', '_wp_preview_meta_filter', 10, 4 );887 888	return $post;889}