convert nested classes in Twitter::Base#attrs

lib/twitter/base.rb

@@ -94,7 +94,11 @@ def [](method)
     # @return [Hash]
     def attrs
       @attrs.inject({}) do |attrs, (key, value)|
-        attrs.merge!(key => respond_to?(key) ? send(key) : value)
+        if value.respond_to?(:attrs)
+          attrs.merge!(key => value.attrs)
+        else
+          attrs.merge!(key => respond_to?(key) ? send(key) : value)
+        end
       end
     end
     alias to_hash attrs

spec/twitter/base_spec.rb

@@ -108,4 +108,15 @@
     end
   end
 
+  describe '#attrs' do
+    it 'returns a hash of attributes' do
+      expect(Twitter::Base.new(:id => 1).attrs).to eq({:id => 1})
+    end
+
+    it 'converts nested classes' do
+      base = Twitter::Base.new(:id => 2, :user => Twitter::User.new(:id => 4))
+      expect(base.attrs).to eq({:id => 2, :user => {:id => 4}})
+    end
+  end
+
 end