From: andrew@avit.ca
To: ruby-core@ruby-lang.org
Subject: [ruby-core:73320] [Ruby trunk - Bug #11595] Time#utc? and Time#gmt? return misleading results based on $TZ
Date: Sat, 23 Jan 2016 18:55:16 +0000 [thread overview]
Message-ID: <redmine.journal-56549.20160123185515.d684fbcd2e754155@ruby-lang.org> (raw)
In-Reply-To: redmine.issue-11595.20151014193359@ruby-lang.org
Issue #11595 has been updated by Andrew Vit.
Careful: not every time with offset 0 is UTC.
A time zone with offset +0100/-0100 may have DST rules, and should not be `utc?`.
----------------------------------------
Bug #11595: Time#utc? and Time#gmt? return misleading results based on $TZ
https://bugs.ruby-lang.org/issues/11595#change-56549
* Author: David Celis
* Status: Open
* Priority: Normal
* Assignee: Akira Tanaka
* ruby -v: ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-darwin14]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
There is an issue with Time#utc? and its alias, Time#gmt?, that return misleading results based on the value of the TZ environment variable. It seems that the only way for a Time instance to return `true` for `utc?` is if you explicitly call `#utc` on it before:
~~~
ENV['TZ'] = 'UTC'
# => "UTC"
time = Time.now
# => 2015-10-14 19:30:00 +0000
time.utc?
# => false
time = time.utc
# => 2015-10-14 19:30:00 UTC
time.utc?
# => true
~~~
This seems misleading based on the value of $TZ being "UTC". The expected result for calling `Time.now.utc?` in this case would be `true`, as would that be expected for time zones that are considered links to "UTC" based on the [tzdata list](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones). These include "UTC", "GMT", "Etc/UTC", "Etc/GMT", "Universal", etc.
---Files--------------------------------
time_utc.patch (927 Bytes)
--
https://bugs.ruby-lang.org/
next prev parent reply other threads:[~2016-01-23 18:21 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <redmine.issue-11595.20151014193359@ruby-lang.org>
2015-10-14 19:34 ` [ruby-core:71089] [Ruby trunk - Bug #11595] [Open] Time#utc? and Time#gmt? return misleading results based on $TZ me
2015-11-30 13:24 ` [ruby-core:71753] [Ruby trunk - Bug #11595] " yasuhiro6194
2015-11-30 13:27 ` [ruby-core:71754] " yasuhiro6194
2015-11-30 16:55 ` [ruby-core:71759] " me
2016-01-23 18:55 ` andrew [this message]
2016-11-05 16:09 ` [ruby-core:77990] [Ruby trunk Bug#11595][Rejected] " akr
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