Entity#serializable_hash returns nil if the represented object is nil.

Author: Michael Bleigh

lib/grape/entity.rb

@@ -118,6 +118,7 @@ def exposures
     #   representation, this is where you can trigger things from conditional options
     #   etc.
     def serializable_hash(runtime_options = {})
+      return nil if object.nil?
       opts = options.merge(runtime_options || {})
       exposures.inject({}) do |output, (attribute, exposure_options)|
         output[key_for(attribute)] = value_for(attribute, opts) if conditions_met?(exposure_options, opts)

spec/grape/entity_spec.rb

@@ -90,6 +90,11 @@
       it 'should not throw an exception if a nil options object is passed' do
         expect{ fresh_class.new(model).serializable_hash(nil) }.not_to raise_error
       end
+
+      it 'should not blow up when the model is nil' do
+        fresh_class.expose :name
+        expect{ fresh_class.new(nil).serializable_hash }.not_to raise_error
+      end
     end
 
     describe '#value_for' do