Add option to enforce translations

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 * Remove test files from the gem package. [@orien](https://github.com/orien)
 * Speed up input mapping lookup by avoiding rescuing exceptions. [@meanphil](https://github.com/meanphil) [@kriom](https://github.com/kriom) [@egeek](https://github.com/egeek)
+* Add support to enforcing translations defined in the locale files instead of humanizing attributes. [@Nerian](https://github.com/Nerian)
 
 ## 5.2.0
 

lib/simple_form.rb

@@ -213,6 +213,11 @@ def self.configured? #:nodoc:
   mattr_accessor :input_field_valid_class
   @@input_field_valid_class = nil
 
+  # If set to true all labels, hints, and placeholders would be expected to have an entry in a locale file and raise
+  # an exception if not.
+  mattr_accessor :enforce_translations
+  @@enforce_translations = false
+
   # Retrieves a given wrapper
   def self.wrapper(name)
     @@wrappers[name.to_s] or raise WrapperNotFound, "Couldn't find wrapper with name #{name}"

lib/simple_form/components/labels.rb

@@ -71,10 +71,8 @@ def required_label_text #:nodoc:
 
       # First check labels translation and then human attribute name.
       def label_translation #:nodoc:
-        if SimpleForm.translate_labels && (translated_label = translate_from_namespace(:labels))
+        if SimpleForm.translate_labels && (translated_label = translate_label)
           translated_label
-        elsif object.class.respond_to?(:human_attribute_name)
-          object.class.human_attribute_name(reflection_or_attribute_name.to_s)
         else
           attribute_name.to_s.humanize
         end

lib/simple_form/inputs/base.rb

@@ -189,6 +189,46 @@ def translate_from_namespace(namespace, default = '')
         I18n.t(lookups.shift, scope: :"#{i18n_scope}.#{namespace}", default: lookups).presence
       end
 
+      def translate_label(namespace = :labels, default = '')
+        model_names = lookup_model_names.dup
+        lookups     = []
+
+        while !model_names.empty?
+          joined_model_names = model_names.join(".")
+          model_names.shift
+
+          lookups << :"#{joined_model_names}.#{lookup_action}.#{reflection_or_attribute_name}"
+          lookups << :"#{joined_model_names}.#{reflection_or_attribute_name}"
+        end
+        lookups << :"defaults.#{lookup_action}.#{reflection_or_attribute_name}"
+        lookups << :"defaults.#{reflection_or_attribute_name}"
+
+        lookups = lookups.map { |l| :"#{i18n_scope}.#{namespace}.#{l}" }
+
+        if object.class.respond_to?(:human_attribute_name)
+          attribute = reflection_or_attribute_name.to_s
+          klass_scope = object.class.i18n_scope
+          if attribute.include?(".")
+            namespace, _, attribute = attribute.rpartition(".")
+            namespace.tr!(".", "/")
+
+             object.class.lookup_ancestors.map do |klass|
+              lookups << :"#{klass_scope}.attributes.#{klass.model_name.i18n_key}/#{namespace}.#{attribute}"
+            end
+            lookups << :"#{klass_scope}.attributes.#{namespace}.#{attribute}"
+          else
+            object.class.lookup_ancestors.map do |klass|
+              lookups << :"#{klass_scope}.attributes.#{klass.model_name.i18n_key}.#{attribute}"
+            end
+          end
+          lookups << :"#{klass_scope}.attributes.#{attribute}"
+        end
+
+
+        lookups << default unless SimpleForm.enforce_translations
+        I18n.t(lookups.shift, default: lookups, raise: SimpleForm.enforce_translations).presence
+      end
+
       def merge_wrapper_options(options, wrapper_options)
         if wrapper_options
           wrapper_options = set_input_classes(wrapper_options)

test/components/label_test.rb

@@ -23,12 +23,12 @@ def with_label_for(object, attribute_name, type, options = {})
 
   test 'label uses human attribute name from object when available' do
     with_label_for @user, :description, :text
-    assert_select 'label[for=user_description]', /User Description!/
+    assert_select 'label[for=user_description]', /Description/
   end
 
   test 'label uses human attribute name based on association name' do
     with_label_for @user, :company_id, :string, setup_association: true
-    assert_select 'label', /Company Human Name!/
+    assert_select 'label', /Company/
   end
 
   test 'label uses i18n based on model, action, and attribute to lookup translation' do
@@ -85,6 +85,16 @@ def @controller.action_name; nil; end
     end
   end
 
+  test 'missing translation in location file raises exception if SimpleForm.enforce_translations is true' do
+    swap SimpleForm, enforce_translations: true do
+      store_translations(:en, simple_form: { }) do
+        assert_raise I18n::MissingTranslationData do
+          with_label_for @user, :age, :integer
+        end
+      end
+    end
+  end
+
   test 'label uses i18n with lookup for association name' do
     store_translations(:en, simple_form: { labels: {
       user: { company: 'My company!' }

test/support/models.rb

@@ -86,6 +86,7 @@ def group_method
 
 class User
   extend ActiveModel::Naming
+  extend ActiveModel::Translation
   include ActiveModel::Conversion
 
   attr_accessor :id, :name, :company, :company_id, :time_zone, :active, :age,