Fix: using 'only' option with exposed attribute that is an entity

Author: estevaoam

.rubocop_todo.yml

@@ -1,34 +1,34 @@
 # This configuration was generated by `rubocop --auto-gen-config`
-# on 2015-03-16 03:40:21 -0300 using RuboCop version 0.28.0.
+# on 2015-03-22 20:12:08 -0300 using RuboCop version 0.28.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 7
+# Offense count: 8
 Metrics/AbcSize:
   Max: 51
 
 # Offense count: 1
 # Configuration parameters: CountComments.
 Metrics/ClassLength:
-  Max: 330
+  Max: 337
 
 # Offense count: 5
 Metrics/CyclomaticComplexity:
   Max: 17
 
-# Offense count: 187
+# Offense count: 175
 # Configuration parameters: AllowURI, URISchemes.
 Metrics/LineLength:
-  Max: 147
+  Max: 146
 
 # Offense count: 7
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
   Max: 32
 
-# Offense count: 4
+# Offense count: 5
 Metrics/PerceivedComplexity:
   Max: 15
 

lib/grape_entity/entity.rb

@@ -499,8 +499,8 @@ def should_return_attribute?(attribute, options)
       only_fields(options).include?(self.class.key_for(attribute))
     end
 
-    def only_fields(options)
-      return {} unless options[:only]
+    def only_fields(options, for_attribute = nil)
+      return nil unless options[:only]
 
       @only_fields ||= options[:only].inject({}) do |allowed_fields, attribute|
         if attribute.is_a?(Hash)
@@ -514,6 +514,12 @@ def only_fields(options)
 
         allowed_fields
       end
+
+      if for_attribute && @only_fields[for_attribute].is_a?(Array)
+        @only_fields[for_attribute]
+      elsif for_attribute.nil?
+        @only_fields
+      end
     end
 
     alias_method :as_json, :serializable_hash
@@ -650,7 +656,8 @@ def options_for_using(attribute, options)
       using_options = options.dup
       using_options.delete(:collection)
       using_options[:root] = nil
-      using_options[:only] = only_fields(using_options)[attribute]
+      using_options[:only] = only_fields(using_options, attribute)
+
       using_options
     end
 

spec/grape_entity/entity_spec.rb

@@ -546,6 +546,19 @@ class Parent < Person
             expect(representation).to eq(id: nil, title: nil)
           end
         end
+
+        context 'attribute that is an entity itself' do
+          it 'returns correctly the children entity attributes' do
+            user_entity = Class.new(Grape::Entity)
+            user_entity.expose(:id, :name, :email)
+
+            subject.expose(:id, :name, :phone)
+            subject.expose(:user, using: user_entity)
+
+            representation = subject.represent(OpenStruct.new(user: {}), only: [:id, :name, :user], serializable: true)
+            expect(representation).to eq(id: nil, name: nil, user: { id: nil, name: nil, email: nil })
+          end
+        end
       end
     end