Bug 3333 - TimeZoneInfo.SupportsDaylightSavingTime always returns True
Summary: TimeZoneInfo.SupportsDaylightSavingTime always returns True
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: 2.10.x
Hardware: Other Other
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-02-09 15:49 UTC by Jon Skeet
Modified: 2015-04-08 09:58 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Jon Skeet 2012-02-09 15:49:08 UTC
TimeZoneInfo.SupportsDaylightSavingTime is documented thusly in MSDN:

"Gets a value indicating whether the time zone has any daylight saving time rules."

I would therefore expect that if it returns true for a particular zone, a call to GetAdjustmentRules() will return a non-empty array - and this is the case in .NET.

Under Mono 2.10.8, *every* TimeZoneInfo reports that it supports daylight saving time, even if it doesn't have any rules.
Comment 1 Adam Brengesjö 2012-06-27 15:50:59 UTC