WordPress at a glance
function is not described

find_core_auto_update() WP 3.7.0

Gets the best available (and enabled) Auto-Update for WordPress Core.

If there's 1.2.3 and 1.3 on offer, it'll choose 1.3 if the installation allows it, else, 1.2.3

No Hooks.

Return

Array/false. False on failure, otherwise the core update offering.

Usage

find_core_auto_update();

Code of find core auto update: wp-admin/includes/update.php WP 5.2.2

<?php
function find_core_auto_update() {
	$updates = get_site_transient( 'update_core' );
	if ( ! $updates || empty( $updates->updates ) ) {
		return false;
	}

	include_once( ABSPATH . 'wp-admin/includes/class-wp-upgrader.php' );

	$auto_update = false;
	$upgrader    = new WP_Automatic_Updater;
	foreach ( $updates->updates as $update ) {
		if ( 'autoupdate' != $update->response ) {
			continue;
		}

		if ( ! $upgrader->should_update( 'core', $update, ABSPATH ) ) {
			continue;
		}

		if ( ! $auto_update || version_compare( $update->current, $auto_update->current, '>' ) ) {
			$auto_update = $update;
		}
	}
	return $auto_update;
}