Ensure I18n format values always have precedence over defaults

Always merge I18n format values, namespaced or not, over the default
ones, to ensure I18n format defaults will have precedence over our
namespaced values.

Precedence should happen like this:

    default :format
    default :namespace :format
    i18n    :format
    i18n    :namespace :format

Because we cannot allow our namespaced default to override a I18n
:format config - ie precision in I18n :format should always have higher
precedence than our default precision for a particular :namespace.

Also simplify default format options logic.

2 files changed, 7 insertions, 1 deletions

diff --git a/activesupport/test/number_helper_i18n_test.rb b/activesupport/test/number_helper_i18n_test.rb
index 4d0d5e8631..65aecece71 100644
--- a/activesupport/test/number_helper_i18n_test.rb
+++ b/activesupport/test/number_helper_i18n_test.rb
@@ -56,6 +56,13 @@ module ActiveSupport
       assert_equal("-$10.00", number_to_currency(-10, :locale => 'empty'))
     end
 
+    def test_locale_default_format_has_precedence_over_helper_defaults
+      I18n.backend.store_translations 'ts',
+        { :number => { :format => { :separator => ";" } } }
+
+      assert_equal("&$ - 10;00", number_to_currency(10, :locale => 'ts'))
+    end
+
     def test_number_to_currency_without_currency_negative_format
       I18n.backend.store_translations 'no_negative_format', :number => {
         :currency => { :format => { :unit => '@', :format => '%n %u' } }
diff --git a/activesupport/test/number_helper_test.rb b/activesupport/test/number_helper_test.rb
index f26d75edfb..5f54587f93 100644
--- a/activesupport/test/number_helper_test.rb
+++ b/activesupport/test/number_helper_test.rb
@@ -369,7 +369,6 @@ module ActiveSupport
           assert number_helper.respond_to?(:valid_float?, true)
         end
       end
-
     end
   end
 end