Fall back to parent locale before it falls back to the :errors namespace

1 files changed, 18 insertions, 2 deletions

diff --git a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
index 703c24b340..993c201f03 100644
--- a/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
+++ b/activerecord/test/cases/validations/i18n_generate_message_validation_test.rb
@@ -4,16 +4,20 @@ require "cases/helper"
 require "models/topic"
 
 class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
+  class Backend < I18n::Backend::Simple
+    include I18n::Backend::Fallbacks
+  end
+
   def setup
     Topic.clear_validators!
     @topic = Topic.new
-    I18n.backend = I18n::Backend::Simple.new
+    I18n.backend = Backend.new
   end
 
   def reset_i18n_load_path
     @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
     I18n.load_path.clear
-    I18n.backend = I18n::Backend::Simple.new
+    I18n.backend = Backend.new
     yield
   ensure
     I18n.load_path.replace @old_load_path
@@ -83,4 +87,16 @@ class I18nGenerateMessageValidationTest < ActiveRecord::TestCase
       assert_equal "Custom taken message", @topic.errors.generate_message(:title, :taken, value: "title")
     end
   end
+
+  test "activerecord attributes scope falls back to parent locale before it falls back to the :errors namespace" do
+    reset_i18n_load_path do
+      I18n.backend.store_translations "en", activerecord: { errors: { models: { topic: { attributes: { title: { taken: "custom en message" } } } } } }
+      I18n.backend.store_translations "en-US", errors: { messages: { taken: "generic en-US fallback" } }
+
+      I18n.with_locale "en-US" do
+        assert_equal "custom en message", @topic.errors.generate_message(:title, :taken, value: "title")
+        assert_equal "generic en-US fallback", @topic.errors.generate_message(:heading, :taken, value: "heading")
+      end
+    end
+  end
 end