Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:39322
Return-Path: <derick@php.net>
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Delivered-To: mailing list internals@lists.php.net
Received: (qmail 90595 invoked from network); 25 Jul 2008 11:12:16 -0000
Received: from unknown (HELO lists.php.net) (127.0.0.1)
  by localhost with SMTP; 25 Jul 2008 11:12:16 -0000
Authentication-Results: pb1.pair.com smtp.mail=derick@php.net; spf=unknown; sender-id=unknown
Authentication-Results: pb1.pair.com header.from=derick@php.net; sender-id=unknown
Received-SPF: unknown (pb1.pair.com: domain php.net does not designate 82.94.239.7 as permitted sender)
X-PHP-List-Original-Sender: derick@php.net
X-Host-Fingerprint: 82.94.239.7 mail.jdi-ict.nl Linux 2.6
Received: from [82.94.239.7] ([82.94.239.7:38307] helo=mail.jdi-ict.nl)
	by pb1.pair.com (ecelerity 2.1.1.9-wez r(12769M)) with ESMTP
	id A1/37-22699-F05B9884 for <internals@lists.php.net>; Fri, 25 Jul 2008 07:12:15 -0400
Received: from localhost (localhost [127.0.0.1])
	by mail.jdi-ict.nl (8.13.7/8.12.11) with ESMTP id m6PBCBMP020513;
	Fri, 25 Jul 2008 13:12:11 +0200
Date: Fri, 25 Jul 2008 13:12:11 +0200 (CEST)
X-X-Sender: derick@kossu.ez.no
To: Jack Steadman <jack@smartertravelmedia.com>
cc: Christian Seiler <chris_se@gmx.net>,
        PHP Developers Mailing List <internals@lists.php.net>
In-Reply-To: <7AFF263C3DBE2549899F71BB925794FF0492A865@sullivan.smartertravelmedia.com>
Message-ID: <alpine.DEB.0.98.0807241547250.1453@kossu.ez.no>
References: <7AFF263C3DBE2549899F71BB925794FF0492A863@sullivan.smartertravelmedia.com>
 <48884251.1020300@gmx.net>
 <7AFF263C3DBE2549899F71BB925794FF0492A865@sullivan.smartertravelmedia.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=UTF-8
Subject: RE: [PHP-DEV] question about backward-compatibility break/bug in
 php 5.2.6
From: derick@php.net (Derick Rethans)

On Thu, 24 Jul 2008, Jack Steadman wrote:

> Thank you for taking the time to explain this to me.  A couple more
> points below:
> 
> > strtotime() has always accepted month and day numbers 0 in order to
> > express "last month of the previos year" and "last day of the previous
> > month". Take:
> 
> So my biggest issue with this is that it's exception-case behavior,
> treating truly invalid dates as valid dates for no obvious reason.  Who
> needs this functionality?  Why is it even a good idea?

It's nice to find the last day of next month. 

> A close second is that this behavior is completely undocumented.
> http://us.php.net/strtotime states that the time argument to strtotime
> is "The string to parse, according to the GNU > Date Input Formats
> syntax" and that false is returned on failure.  GNU date formats do NOT
> allow for zero months and days (see
> http://www.gnu.org/software/tar/manual/html_node/Calendar-date-items.htm
> l#SEC116).  No official mention is made of the exception case that you
> describe.  The closest the docs come is a user comment on the strtotime
> page from June 19 of this year (perhaps someone who upgraded to 5.2.6
> and found this behavior for the first time?) warning other users that
> 2008-00-14 is interpreted as 2007-12-14.

Yes, the documentation is broken. I'm working on fixing that.

> This is not actually the case.  Take one of our machines (first part of
> php -i included here):

<snip>

> This 64-bit machine is running 5.2.5 and returns false on the all-zero
> datetime string.  It was upgraded last week to 5.2.6 and started
> returning the large negative integer.

<snip>

> *Something* changed in date handling between 5.2.5 and 5.2.6.  Whether
> you perpetuate the exception case or not, it *is* a regression.

Yes, because there was a regression in 5.2.[45]:

php-5.2.6$ sapi/cli/php -n -r 'var_dump( strtotime( "0000-00-00 00:00" ) );'
int(-62169987600)

php-5.2.5$ sapi/cli/php -n -r 'var_dump( strtotime( "0000-00-00 00:00" ) );'
bool(false)

php-5.2.4$ sapi/cli/php -n -r 'var_dump( strtotime( "0000-00-00 00:00" ) );'
bool(false)

even in PHP 5.1 it doesn't return false (although it's incorrect):

$ php-5.1dev -n -r 'var_dump( strtotime( "0000-00-00 00:00" ) );' 
int(943916400)

and *even* on 4.3.9:

$ php-4.3.9 -n -r 'var_dump( strtotime( "0000-00-00 00:00" ) );'
int(943916400)

regards,
Derick

-- 
HEAD before 5_3!: http://tinyurl.com/6d2esb
http://derickrethans.nl | http://ezcomponents.org | http://xdebug.org