Fix #215: allow delegate_attribute for derived entity.

Author: Batykov Stepan

CHANGELOG.md

@@ -2,11 +2,13 @@
 ============
 
 * [#215](https://github.com/ruby-grape/grape-entity/pull/217): Fix: `#delegate_attribute` no longer delegates to methods included with `Kernel` - [@maltoe](https://github.com/maltoe).
-* [#219](https://github.com/ruby-grape/grape-entity/pull/219): Fix: double pass options in serializable_hash - [@sbatykov](https://github.com/sbatykov).
-* [#226](https://github.com/ruby-grape/grape-entity/pull/226): Added fetch method to fetch from opts_hash - [@alanjcfs](https://github.com/alanjcfs).
+* [#219](https://github.com/ruby-grape/grape-entity/pull/219): Fix: double pass options in `serializable_hash` - [@sbatykov](https://github.com/sbatykov).
+* [#226](https://github.com/ruby-grape/grape-entity/pull/226): Added `fetch` from `opts_hash` - [@alanjcfs](https://github.com/alanjcfs).
 * [#232](https://github.com/ruby-grape/grape-entity/pull/232), [#213](https://github.com/ruby-grape/grape-entity/issues/213): Added `#kind_of?` and `#is_a?` to `OutputBuilder` to get an exact class of an `output` object - [@avyy](https://github.com/avyy).
 * [#234](https://github.com/ruby-grape/grape-entity/pull/234), [#233](https://github.com/ruby-grape/grape-entity/issues/233): Added ruby version checking in `Gemfile` to install needed gems versions for supporting old rubies too - [@avyy](https://github.com/avyy).
 * [#237](https://github.com/ruby-grape/grape-entity/pull/237): Added Danger, PR linter - [@dblock](https://github.com/dblock).
+* [#226](https://github.com/ruby-grape/grape-entity/pull/226): Add fetch method to fetch from opts_hash - [@alanjcfs](https://github.com/alanjcfs).
+* [#231](https://github.com/ruby-grape/grape-entity/pull/231), [#215](https://github.com/ruby-grape/grape-entity/issues/215): Fix: allow `delegate_attribute` for derived entity - [@sbatykov](https://github.com/sbatykov).
 * Your contribution here.
 
 0.5.1 (2016-4-4)

lib/grape_entity/entity.rb

@@ -478,7 +478,7 @@ def value_for(key, options = Options.new)
     end
 
     def delegate_attribute(attribute)
-      if respond_to?(attribute, true) && method(attribute).owner == self.class
+      if respond_to?(attribute, true) && Grape::Entity > method(attribute).owner
         send(attribute)
       else
         delegator.delegate(attribute)

spec/grape_entity/entity_spec.rb

@@ -1524,12 +1524,13 @@ class FriendEntity < Grape::Entity
         expect(subject.value_for(:fantasies)).to eq ['Nessy', 'Double Rainbows', 'Unicorns']
       end
 
-      it 'tries instance methods on the entity first' do
+      context 'delegate_attribute' do
         module EntitySpec
           class DelegatingEntity < Grape::Entity
             root 'friends', 'friend'
             expose :name
             expose :email
+            expose :system
 
             private
 
@@ -1539,26 +1540,33 @@ def name
           end
         end
 
-        friend = double('Friend', name: 'joe', email: '[email protected]')
-        rep = EntitySpec::DelegatingEntity.new(friend)
-        expect(rep.value_for(:name)).to eq 'cooler name'
-        expect(rep.value_for(:email)).to eq '[email protected]'
+        it 'tries instance methods on the entity first' do
+          friend = double('Friend', name: 'joe', email: '[email protected]')
+          rep = EntitySpec::DelegatingEntity.new(friend)
+          expect(rep.value_for(:name)).to eq 'cooler name'
+          expect(rep.value_for(:email)).to eq '[email protected]'
 
-        another_friend = double('Friend', email: '[email protected]')
-        rep = EntitySpec::DelegatingEntity.new(another_friend)
-        expect(rep.value_for(:name)).to eq 'cooler name'
-      end
+          another_friend = double('Friend', email: '[email protected]')
+          rep = EntitySpec::DelegatingEntity.new(another_friend)
+          expect(rep.value_for(:name)).to eq 'cooler name'
+        end
+
+        it 'does not delegate Kernel methods' do
+          foo = double 'Foo', system: 'System'
+          rep = EntitySpec::DelegatingEntity.new foo
+          expect(rep.value_for(:system)).to eq 'System'
+        end
 
-      it 'does not delegate to Kernel methods' do
         module EntitySpec
-          class DelegatingEntity < Grape::Entity
-            expose :system
+          class DerivedEntity < DelegatingEntity
           end
         end
 
-        foo = double 'Foo', system: 'System'
-        rep = EntitySpec::DelegatingEntity.new foo
-        expect(rep.value_for(:system)).to eq 'System'
+        it 'derived entity get methods from base entity' do
+          foo = double 'Foo', name: 'joe'
+          rep = EntitySpec::DerivedEntity.new foo
+          expect(rep.value_for(:name)).to eq 'cooler name'
+        end
       end
 
       context 'using' do