Forum: Ruby-core DateTime.strptime() doesn't work correctly for '%s %z'

31e9336577dcba34f9ea8025a763c900?d=identicon&s=25 unknown (Guest)
on 2014-05-04 10:50
(Received via mailing list)
Issue #9794 has been updated by tadayoshi funaba.


Akira Tanaka wrote:
> tadayoshi funaba wrote:

> もしかして、DateTime.strptime に与えるフォーマットに時刻 (時間軸上の点) を同定するのに関係しない要素は与えるべきでない、
> と感じるという話でしょうか。

極端な話、単に読み飛ばすだけでも意味があると思ってます。

`s = 'Sunday 4 May <unknown garbage> 2014; blob'
h = Date._strptime(s, '%a %d %b')
s2 = h[:leftover].gsub(/ *<.*> */, '')
h2 = Date._strptime(s2, '%Y')`

h.merge(h2) #=> {:wday=>0, :mday=>4, :mon=>5, :leftover=>"; blob",
:year=>2014}

もちろん strptime でも。
結果的に捨てる部分がでてくるのは避けられないんじゃないですかね。


----------------------------------------
Bug #9794: DateTime.strptime() doesn't work correctly for '%s %z'
https://bugs.ruby-lang.org/issues/9794#change-46501

* Author: Felipe Contreras
* Status: Rejected
* Priority: Low
* Assignee: tadayoshi funaba
* Category: ext
* Target version:
* ruby -v: 2.1.1p76
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
Time.strptime() works correctly:

    Time.strptime('0 +0100', '%s %z').strftime('%s %z')
    => "0 +0100"

But DateTime.strptime() doesn't:

    DateTime.strptime('0 +0100', '%s %z').strftime('%s %z')
    => "0 +0000"

In Rubinious it does work correctly:

    DateTime.strptime('0 +0100', '%s %z').strftime('%s %z')
    => "0 +0100"

This make the RubySL date space fail:

    DateTime#strptime parses seconds and timezone correctly FAILED
    Expected "1970-01-01T00:00:00+00:00"
     to equal "1970-01-01T01:00:00+01:00"

In addition, both C and perl preserver the offset correctly when doing
'%s %z'.

So it's very clear DateTime.strptime() has to be fixed.

Patch attached.

---Files--------------------------------
0001-datetime-fix-strptime-s-z.patch (1.94 KB)
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