Don't disable new invalid translations

After adding a new translation with invalid data and sending the form,
we were disabling the new translation when displaying the form again to
the user, which was confusing.

app/helpers/globalize_helper.rb

@@ -23,7 +23,9 @@ module GlobalizeHelper
   end
 
   def enable_locale?(resource, locale)
-    resource.translated_locales.include?(locale) || locale == I18n.locale
+    # Use `map` instead of `pluck` in order to keep the `params` sent
+    # by the browser when there's invalid data
+    resource.translations.map(&:locale).include?(locale) || locale == I18n.locale
   end
 
   def highlight_current?(locale)

app/helpers/translatable_form_helper.rb

@@ -25,7 +25,6 @@ module TranslatableFormHelper
           fields_for(:translations, translation_for(locale), builder: TranslationsFieldsBuilder) do |translations_form|
             @template.concat translations_form.hidden_field(
               :_destroy,
-              value: !@template.enable_locale?(@object, locale),
               class: "destroy_locale",
               data: { locale: locale })
 
@@ -48,7 +47,9 @@ module TranslatableFormHelper
     end
 
     def new_translation_for(locale)
-      @object.translations.new(locale: locale)
+      @object.translations.new(locale: locale).tap do |translation|
+        translation.mark_for_destruction unless locale == I18n.locale
+      end
     end
   end
 

spec/shared/features/translatable.rb

@@ -60,6 +60,23 @@ shared_examples "translatable" do |factory_name, path_name, fields|
       expect(page).to have_field(field_for(field, :fr), with: text_for(field, :fr))
     end
 
+    scenario "Add an invalid translation", :js do
+      skip("can't have invalid translations") if required_fields.empty?
+
+      field = required_fields.sample
+
+      visit path
+      select "Français", from: "translation_locale"
+      fill_in field_for(field, :fr), with: ""
+      click_button update_button_text
+
+      expect(page).to have_css "#error_explanation"
+
+      click_link "Français"
+
+      expect(page).to have_field(field_for(field, :fr), with: "")
+    end
+
     scenario "Update a translation", :js do
       visit path