Merge pull request #45675 from hirotaka/fix_date_select_with_locale

jonathanhefner · jonathanhefner · commit b3e79be9c6f1 · 2022-08-09T11:33:02.000-05:00
Fixes Date Helper with locale (cherry picked from commit 3661d0d)
diff --git a/actionview/lib/action_view/helpers/date_helper.rb b/actionview/lib/action_view/helpers/date_helper.rb
@@ -888,7 +888,7 @@ def set_day_if_discarded
         def month_names
           @month_names ||= begin
             month_names = @options[:use_month_names] || translated_month_names
-            month_names.unshift(nil) if month_names.size < 13
+            month_names = [nil, *month_names] if month_names.size < 13
             month_names
           end
         end
diff --git a/actionview/test/template/date_helper_i18n_test.rb b/actionview/test/template/date_helper_i18n_test.rb
@@ -114,6 +114,16 @@ def test_select_month_given_use_short_month_option_translates_abbr_monthnames
     end
   end
 
+  def test_select_month_with_frozen_month_names
+    month_names = Date::MONTHNAMES.dup.drop(1).freeze
+
+    assert_called_with(I18n, :translate, [:'date.month_names', locale: "en"], returns: month_names) do
+      select_month(8, locale: "en")
+    end
+  end
+
+  # date_or_time_select
+
   def test_date_or_time_select_translates_prompts
     prompt_defaults = { year: "Year", month: "Month", day: "Day", hour: "Hour", minute: "Minute", second: "Seconds" }
     defaults = { [:'date.order', locale: "en", default: []] => %w(year month day) }
@@ -137,8 +147,6 @@ def test_date_or_time_select_translates_prompts
     assert_equal defaults.count, @prompt_called
   end
 
-  # date_or_time_select
-
   def test_date_or_time_select_given_an_order_options_does_not_translate_order
     assert_not_called(I18n, :translate) do
       datetime_select("post", "updated_at", order: [:year, :month, :day], locale: "en", use_month_names: Date::MONTHNAMES)
