Merge pull request ruby-grape#48 from Matchbook/master

regard an exposure as safe if its nested exposures are safe

Author: dblock

lib/grape_entity/entity.rb

@@ -388,10 +388,14 @@ def self.key_for(attribute)
       exposures[attribute.to_sym][:as] || name_for(attribute)
     end
 
+    def self.nested_exposures_for(attribute)
+      exposures.select { |a, _| a.to_s =~ /^#{attribute}__/ }
+    end
+
     def value_for(attribute, options = {})
       exposure_options = exposures[attribute.to_sym]
 
-      nested_exposures = exposures.select { |a, _| a.to_s =~ /^#{attribute}__/ }
+      nested_exposures = self.class.nested_exposures_for(attribute)
 
       if exposure_options[:using]
         using_options = options.dup
@@ -438,6 +442,8 @@ def delegate_attribute(attribute)
     end
 
     def valid_exposure?(attribute, exposure_options)
+      nested_exposures = self.class.nested_exposures_for(attribute)
+      (nested_exposures.any? && nested_exposures.all? { |a, o| valid_exposure?(a, o) }) || \
       exposure_options.has_key?(:proc) || \
       !exposure_options[:safe] || \
       object.respond_to?(self.class.name_for(attribute))

spec/grape_entity/entity_spec.rb

@@ -105,6 +105,21 @@ class BogusEntity < Grape::Entity
               another_nested: "value"
             }
           end
+
+          it 'is safe if its nested exposures are safe' do
+            subject.with_options safe: true do
+              subject.expose :awesome do
+                subject.expose(:nested) { |_| "value" }
+              end
+              subject.expose :not_awesome do
+                subject.expose :nested
+              end
+            end
+
+            valid_keys = subject.represent({}).valid_exposures.keys
+            valid_keys.include?(:awesome).should == true && \
+            valid_keys.include?(:not_awesome).should == false
+          end
         end
       end