WordPress: Timestamp to date/time

timestamp-to-date-time.php

<?php
/**
 * Formats a timestamp into a date and time based on WordPress settings.
 *
 * @param  int    $timestamp The timestamp.
 * @param  string $format    Optional date time format.
 * @return string
 */
function timestamp_to_date_time( $timestamp, $format = false ) {

	if ( empty( $format ) ) {
		$format = get_option( 'date_format' ) . ' ' . get_option( 'time_format' );
	}

	$tzstring  = get_option( 'timezone_string' );
	$date_time = null;

	if ( ! empty( $tzstring ) ) {
		$date_time = new \DateTime( 'now', new \DateTimeZone( $tzstring ) );
	} else {
		$date_time = new \DateTime( 'now' );
	}

	$date_time->setTimestamp( $timestamp );

	return $date_time->format( $format );
}