1--TEST--
2DateTime::modify() with empty string as format
3--FILE--
4<?php
5
6$datetime = new DateTime;
7var_dump(date_modify($datetime, ''));
8try {
9	var_dump($datetime->modify(''));
10} catch (DateMalformedStringException $e) {
11	echo $e::class, ': ', $e->getMessage(), "\n";
12}
13
14?>
15--EXPECTF--
16Warning: date_modify(): Failed to parse time string () at position 0 ( ): Empty string in %s
17bool(false)
18DateMalformedStringException: DateTime::modify(): Failed to parse time string () at position 0 ( ): Empty string
19