Merge pull request #18777 from yasyf/issue_15209

Take DST into account when locating TimeZone from Numeric

1 files changed, 7 insertions, 1 deletions

diff --git a/activesupport/lib/active_support/values/time_zone.rb b/activesupport/lib/active_support/values/time_zone.rb
index da39f0d245..ab6a78052c 100644
--- a/activesupport/lib/active_support/values/time_zone.rb
+++ b/activesupport/lib/active_support/values/time_zone.rb
@@ -239,7 +239,7 @@ module ActiveSupport
           end
           when Numeric, ActiveSupport::Duration
             arg *= 3600 if arg.abs <= 13
-            all.find { |z| z.utc_offset == arg.to_i }
+            all.find { |z| z.utc_total_offset == arg.to_i }
           else
             raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
         end
@@ -285,6 +285,12 @@ module ActiveSupport
       end
     end
 
+    # Returns the offset of this time zone from UTC in seconds,
+    # taking DST into account.
+    def utc_total_offset
+      tzinfo.current_period.utc_total_offset if tzinfo
+    end
+
     # Returns the offset of this time zone as a formatted string, of the
     # format "+HH:MM".
     def formatted_offset(colon=true, alternate_utc_string = nil)