Edit report at https://bugs.php.net/bug.php?id=55575&edit=1
ID: 55575
Updated by: salathe@php.net
Reported by: vlayne dot tech+bugsphp at gmail dot com
Summary: strtotime() returns erroneous result on nonsense
DATE_RSS format date strings
-Status: Open
+Status: Not a bug
Type: Bug
Package: Date/time related
Operating System: Linux & Darwin
PHP Version: 5.3.8
Block user comment: N
Private report: N
New Comment:
Date strings sent to strtotime() can consist of absolute and relative parts.
For "Tue, 9 May 2010 04:24:36 GMT":
- absolute parts are processed first "9 May 2010 04:24:36 GMT"
- then, the relative part "Tue" is processed
This last step, as detailed on the Relative Formats [1] manual page, shifts the date to the 11th,
which is the next Tuesday.
This behaviour makes much more sense than ignoring parts of the subject date string, or disallowing
relative date parts and instead throwing an error.
[1] http://php.net/datetime.formats.relative
Previous Comments:
------------------------------------------------------------------------
[2014-07-17 12:40:24] datibbaw@php.net
How are we supposed to properly handle nonsense? How are you sure that what you have proposed is the
correct way of dealing with this? Have you seen other implementations that do this?
------------------------------------------------------------------------
[2011-09-03 04:04:09] vlayne dot tech+bugsphp at gmail dot com
Description:
------------
(Note: I was only able to test on 5.2.16, 5.3.0, and 5.3.4. Since there is no
evidence of it being fixed in the changelog of 5.3.8, I assume it's still there.)
The ninth of May, 2010, was a Sunday. However, if you assert to strtotime() that
it was a Monday, it will return the Unix timestamp for Monday, May 10th. Likewise
if you assert the ninth was a Tuesday, it will return the timestamp for the 11th;
a Wednesday the 12th, and so on right up to returning a Unix timestamp for
Saturday, 15 May 2010 if you provide it with "Saturday, 9 May 2010".
Presumably, the correct behavior is one of (1) to throw an error given a self-
contradictory date, (2) to return nothing at all, or (3) to ignore the day-of-the-
week element and return the Unix timestamp for the date specified (e.g. 9 May
2010). Returning the timestamp for another date altogether is wrong.
Test script:
---------------
$datestring="9 May 2010 04:24:36 GMT";
print "\"\": ".strtotime($datestring)." ".date($dateformat,
strtotime($datestri\
ng)) ."\n";
$datestring="Sun, 9 May 2010 04:24:36 GMT";
print "Sun: ".strtotime($datestring)." ".date($dateformat, strtotime($datestrin\
g)) ."\n";
$datestring="Mon, 9 May 2010 04:24:36 GMT";
print "Mon: ".strtotime($datestring)." ".date($dateformat, strtotime($datestrin\
g)) ."\n";
$datestring="Tue, 9 May 2010 04:24:36 GMT";
print "Tue: ".strtotime($datestring)." ".date($dateformat, strtotime($datestrin\
g)) ."\n";
Expected result:
----------------
"": 1273379076 Sun, 09 May 2010 00:24:36 -0400
Sun: 1273379076 Sun, 09 May 2010 00:24:36 -0400
Mon: 1273379076 Sun, 09 May 2010 00:24:36 -0400
Tue: 1273379076 Sun, 09 May 2010 00:24:36 -0400
(Alternatively:
"": 1273379076 Sun, 09 May 2010 00:24:36 -0400
Sun: 1273379076 Sun, 09 May 2010 00:24:36 -0400
Mon:
Tue:
)
Actual result:
--------------
"": 1273379076 Sun, 09 May 2010 00:24:36 -0400
Sun: 1273379076 Sun, 09 May 2010 00:24:36 -0400
Mon: 1273465476 Mon, 10 May 2010 00:24:36 -0400
Tue: 1273551876 Tue, 11 May 2010 00:24:36 -0400
------------------------------------------------------------------------
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Edit this bug report at https://bugs.php.net/bug.php?id=55575&edit=1