Update inspect method to handle nil serializable_hash

CHANGELOG.md

@@ -7,7 +7,7 @@
 #### Fixes
 
 * Your contribution here.
-
+* [#384](https://github.com/ruby-grape/grape-entity/pull/384): Fix `inspect` to correctly handle `nil` values - [@fcce](https://github.com/fcce).
 
 ### ### 1.0.1 (2024-04-10)
 

lib/grape_entity/entity.rb

@@ -472,8 +472,13 @@ def presented
 
     # Prevent default serialization of :options or :delegator.
     def inspect
-      fields = serializable_hash.map { |k, v| "#{k}=#{v}" }
-      "#<#{self.class.name}:#{object_id} #{fields.join(' ')}>"
+      object = serializable_hash
+      if object.nil?
+        "#<#{self.class.name}:#{object_id}> nil"
+      else
+        fields = object.map { |k, v| "#{k}=#{v}" }
+        "#<#{self.class.name}:#{object_id} #{fields.join(' ')}>"
+      end
     end
 
     def initialize(object, options = {})

spec/grape_entity/entity_spec.rb

@@ -1769,6 +1769,12 @@ class NoPathCharacterEntity < Grape::Entity
         expect(data).to_not include '@options'
         expect(data).to_not include '@delegator'
       end
+
+      it 'returns a nil string when subject is nil' do
+        data = subject.class.new(nil).inspect
+        expect(data).to include 'nil'
+      end
+
     end
 
     describe '#value_for' do