1 files changed, 23 insertions, 6 deletions
diff --git a/railties/lib/rails/tasks/misc.rake b/railties/lib/rails/tasks/misc.rake
index 4195106961..371bcb8fe0 100644
--- a/railties/lib/rails/tasks/misc.rake
+++ b/railties/lib/rails/tasks/misc.rake
@@ -10,29 +10,46 @@ task about: :environment do
 end
 
 namespace :time do
+  desc 'List all time zones, list by two-letter country code (`rake time:zones[US]`), or list by UTC offset (`rake time:zones[-8]`)'
+  task :zones, :country_or_offset do |t, args|
+    zones, offset = ActiveSupport::TimeZone.all, nil
+
+    if country_or_offset = args[:country_or_offset]
+      begin
+        zones = ActiveSupport::TimeZone.country_zones(country_or_offset)
+      rescue TZInfo::InvalidCountryCode
+        offset = country_or_offset
+      end
+    end
+
+    build_time_zone_list zones, offset
+  end
+
   namespace :zones do
-    desc 'Displays all time zones, also available: time:zones:us, time:zones:local -- filter with OFFSET parameter, e.g., OFFSET=-6'
+    # desc 'Displays all time zones, also available: time:zones:us, time:zones:local -- filter with OFFSET parameter, e.g., OFFSET=-6'
     task :all do
-      build_time_zone_list(:all)
+      build_time_zone_list ActiveSupport::TimeZone.all
     end
 
     # desc 'Displays names of US time zones recognized by the Rails TimeZone class, grouped by offset. Results can be filtered with optional OFFSET parameter, e.g., OFFSET=-6'
     task :us do
-      build_time_zone_list(:us_zones)
+      build_time_zone_list ActiveSupport::TimeZone.us_zones
     end
 
     # desc 'Displays names of time zones recognized by the Rails TimeZone class with the same offset as the system local time'
     task :local do
       require 'active_support'
       require 'active_support/time'
+
       jan_offset = Time.now.beginning_of_year.utc_offset
       jul_offset = Time.now.beginning_of_year.change(month: 7).utc_offset
       offset = jan_offset < jul_offset ? jan_offset : jul_offset
-      build_time_zone_list(:all, offset)
+
+      build_time_zone_list(ActiveSupport::TimeZone.all, offset)
     end
 
     # to find UTC -06:00 zones, OFFSET can be set to either -6, -6:00 or 21600
-    def build_time_zone_list(method, offset = ENV['OFFSET'])
+    def build_time_zone_list(zones, offset = ENV['OFFSET'])
       require 'active_support'
       require 'active_support/time'
       if offset
@@ -47,7 +64,7 @@ namespace :time do
         end
       end
       previous_offset = nil
-      ActiveSupport::TimeZone.__send__(method).each do |zone|
+      zones.each do |zone|
         if offset.nil? || offset == zone.utc_offset
           puts "\n* UTC #{zone.formatted_offset} *" unless zone.utc_offset == previous_offset
           puts zone.name