Merge pull request rails#53199 from bogdan/time-zone-standard-name

Add AS::TimeZone#standard_name method

Author: rafaelfranca

activesupport/CHANGELOG.md

@@ -1,3 +1,15 @@
+*   Add `ActiveSupport::TimeZone#standard_name` method.
+
+    ``` ruby
+    zone = ActiveSupport::TimeZone['Hawaii']
+    # Old way
+    ActiveSupport::TimeZone::MAPPING[zone.name]
+    # New way
+    zone.standard_name # => 'Pacific/Honolulu'
+    ```
+
+    *Bogdan Gusiev*
+
 *   Add Structured Event Reporter, accessible via `Rails.event`.
 
     The Event Reporter provides a unified interface for producing structured events in Rails

activesupport/lib/active_support/values/time_zone.rb

@@ -314,6 +314,12 @@ def initialize(name, utc_offset = nil, tzinfo = nil)
     end
     # :startdoc:
 
+    # Returns a standard time zone name defined by IANA
+    # https://www.iana.org/time-zones
+    def standard_name
+      MAPPING[name] || name
+    end
+
     # Returns the offset of this time zone from UTC in seconds.
     def utc_offset
       @utc_offset || tzinfo&.current_period&.base_utc_offset

activesupport/test/time_zone_test.rb

@@ -920,4 +920,10 @@ def test_works_as_ruby_time_zone
     assert_equal "EDT", time.strftime("%Z")
     assert_equal true, time.isdst
   end
+
+  def test_standard_name
+    assert_equal "America/New_York", ActiveSupport::TimeZone["Eastern Time (US & Canada)"].standard_name
+    assert_equal "America/Montevideo", ActiveSupport::TimeZone["Montevideo"].standard_name
+    assert_equal "America/Toronto", ActiveSupport::TimeZone["America/Toronto"].standard_name
+  end
 end