php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login

go to bug id or search bugs for

Bug #74681 createFromFormat incorrect behavior if no day provided
Submitted: 2017-05-31 15:14 UTC Modified: 2017-05-31 15:45 UTC
From: raul at reyes dot solutions Assigned:
Status: Not a bug Package: Date/time related
PHP Version: Irrelevant OS: Any
Private report: No CVE-ID: None
View Developer Edit
 [2017-05-31 15:14 UTC] raul at reyes dot solutions 
Description:
------------
Seems to default all dates to 31. if trying to create February of 2018 for example it defaults to March 3rd. 

DateTime::createFromFormat('my',"0218")

sets the date to 2018-03-03. I would think the correct behavior is setting the date to 01 (or maybe the last day 't')

Test script:
---------------
$date = DateTime::createFromFormat('my',"0218");
echo $date->format('Y-m-t') . " when expecting 2018-02-01";

Expected result:
----------------
2018-02-01

Actual result:
--------------
2018-03-03

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2017-05-31 15:38 UTC] derick@php.net
-Status: Open +Status: Not a bug
 [2017-05-31 15:38 UTC] derick@php.net 
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php

By default, all the fields are prefilled in with the current year/month/day values.

So my with 0218 becomes "2017-02-31", which overflows to 2017-03-03. You can prevent this by using the ! format specifier before "my" or the "|" specifier behind the "my" to set all values to 1970-01-01 00:00:00 first:


<?php
var_dump(DateTime::createFromFormat('!my',"0218"));
var_dump(DateTime::createFromFormat('my|',"0218"));
?>

your "Actual result" is not "2018-03-03" btw, it's "2018-03-31" as "t" is the number of days in the month (3), which is 31.
 [2017-05-31 15:45 UTC] raul at reyes dot solutions 
oops, meant to change the t to a d ... thanks for letting me know about ! and | modifiers,
 
PHP Copyright © 2001-2025 The PHP Group
All rights reserved. 		Last updated: Mon Dec 22 12:00:01 2025 UTC