Bug #65730 [Nab]: DateTime::format('W') returns wrong week number
Edit report at https://bugs.php.net/bug.php?id=65730edit=1
ID: 65730
Updated by: ras...@php.net
Reported by:glavic at gmail dot com
Summary:DateTime::format('W') returns wrong week number
Status: Not a bug
Type: Bug
Package:Date/time related
Operating System: ALL
PHP Version:Irrelevant
Block user comment: N
Private report: N
New Comment:
2013-12-30 ('Y W'); returns 2013 01 is correct. The 'Y' is the year. The ISO
8601 Year for 2013-12-30 is obviously 2013. However the ISO 8601 Week number
for
2013-12-30 is also just as obviously 1. So 2013 01 is correct.
And your next statement makes no sense either:
So now we have two identical week number for year 2013 with a year difference
between dates ;)
We are talking about Dec.30 and 31 in 2013. That is Monday and Tuesday. They
both fall in ISO week 1 and they are both in 2013. Wednesday Jan.1 2014 also
falls in ISO week 1 even though it is in 2014. That's how ISO weeks work.
Is your confusion that you think the 'Y' has to be associated with the 'W'
somehow? The 'Y' refers to the date you are formatting.
Previous Comments:
[2013-09-21 18:05:44] glavic at gmail dot com
@rasmus: I never said nothing about first or last week of the month containing
dates from before/after year. You probably agree with statement that the last
week of the year 2013 (and first week of the year 2014) is from 2013-12-30 to
2014-01-05?
I reported this, not because what you said, but because code echo (new
DateTime('2013-12-30'))-format('Y W'); returns 2013 01 which is incorrect,
and for me this is bug. This should, like I already said in report, return
2014 01.
Code echo (new DateTime('2012-12-31'))-format('Y W'); also returns 2013
01. So now we have two identical week number for year 2013 with a year
difference between dates ;)
[2013-09-21 14:33:53] ras...@php.net
PHP uses the ISO 8601 standard for day, month and week numbers. This is pretty
clearly documented and if you read ISO 8601 it states that the first week of
the
year is the week with the year's first Thursday in it and since ISO 8601
weeks
start on Mondays, it is quite normal for the first ISO week to contain days
from
a previous year. If they didn't then it would be impossible to consistently
start
weeks on Mondays since Jan.1 is not always a Monday. If you apply the ISO 8601
definition to the dates in question here you will find PHP is quite correct
here.
[2013-09-21 11:04:29] glavic at gmail dot com
Description:
DateTime::format('W') returns wrong week number when date is 2013-12-30 or
2013-12-31.
Test script:
---
?php
$dt = new DateTime;
for ($w = 52; $w = 54; $w++) {
$dt-setISODate(2013, $w);
print_r($dt);
echo $dt-format('Y W') . \n\n;
}
# see this script running on all php versions http://3v4l.org/9aua5
Expected result:
DateTime Object
(
[date] = 2013-12-23 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2013 52
DateTime Object
(
[date] = 2013-12-30 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2014 01 # or 2013 53, but surely not 2013 01 !!!
DateTime Object
(
[date] = 2014-01-06 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2014 02
Actual result:
--
DateTime Object
(
[date] = 2013-12-23 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2013 52
DateTime Object
(
[date] = 2013-12-30 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2013 01
DateTime Object
(
[date] = 2014-01-06 11:02:12
[timezone_type] = 3
[timezone] = UTC
)
2014 02
--
Edit this bug report at https://bugs.php.net/bug.php?id=65730edit=1
Bug #65730 [Nab]: DateTime::format('W') returns wrong week number
Edit report at https://bugs.php.net/bug.php?id=65730edit=1
ID: 65730
Updated by: der...@php.net
Reported by:glavic at gmail dot com
Summary:DateTime::format('W') returns wrong week number
Status: Not a bug
Type: Bug
Package:Date/time related
Operating System: ALL
PHP Version:Irrelevant
Block user comment: N
Private report: N
New Comment:
Nope, we won't delete it so that we can point other people to it in the future.
Previous Comments:
[2013-09-21 18:51:06] glavic at gmail dot com
Ah, I found it, it is 'o' format character.
Sorry for your trouble. Can you delete this failed bug report? ;)
Tnx
[2013-09-21 18:48:10] glavic at gmail dot com
I made a copy/paste typo before, but that doesn't matter now because you said
that 'Y' returns the year of the date, which is totally correct, where was my
head...
I understand what you are saying; I agree that Dec 30 and 31 fall in week 1;
but year 2014, not 2013.
Maybe I should rephrase my question: how do I get correct week year from echo
(new DateTime('2013-12-30'))-format('W '); ?
[2013-09-21 18:18:50] ras...@php.net
2013-12-30 ('Y W'); returns 2013 01 is correct. The 'Y' is the year. The ISO
8601 Year for 2013-12-30 is obviously 2013. However the ISO 8601 Week number
for
2013-12-30 is also just as obviously 1. So 2013 01 is correct.
And your next statement makes no sense either:
So now we have two identical week number for year 2013 with a year difference
between dates ;)
We are talking about Dec.30 and 31 in 2013. That is Monday and Tuesday. They
both fall in ISO week 1 and they are both in 2013. Wednesday Jan.1 2014 also
falls in ISO week 1 even though it is in 2014. That's how ISO weeks work.
Is your confusion that you think the 'Y' has to be associated with the 'W'
somehow? The 'Y' refers to the date you are formatting.
[2013-09-21 18:05:44] glavic at gmail dot com
@rasmus: I never said nothing about first or last week of the month containing
dates from before/after year. You probably agree with statement that the last
week of the year 2013 (and first week of the year 2014) is from 2013-12-30 to
2014-01-05?
I reported this, not because what you said, but because code echo (new
DateTime('2013-12-30'))-format('Y W'); returns 2013 01 which is incorrect,
and for me this is bug. This should, like I already said in report, return
2014 01.
Code echo (new DateTime('2012-12-31'))-format('Y W'); also returns 2013
01. So now we have two identical week number for year 2013 with a year
difference between dates ;)
[2013-09-21 14:33:53] ras...@php.net
PHP uses the ISO 8601 standard for day, month and week numbers. This is pretty
clearly documented and if you read ISO 8601 it states that the first week of
the
year is the week with the year's first Thursday in it and since ISO 8601
weeks
start on Mondays, it is quite normal for the first ISO week to contain days
from
a previous year. If they didn't then it would be impossible to consistently
start
weeks on Mondays since Jan.1 is not always a Monday. If you apply the ISO 8601
definition to the dates in question here you will find PHP is quite correct
here.
The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
https://bugs.php.net/bug.php?id=65730
--
Edit this bug report at https://bugs.php.net/bug.php?id=65730edit=1
