Merge pull request #322 from G5/no_class

Raise error if model class is nil

Author: lgebhardt

lib/jsonapi/resource.rb

@@ -621,7 +621,10 @@ def paginator(paginator)
       end
 
       def _model_class
-        @model ||= _model_name.to_s.safe_constantize
+        return @model if @model
+        @model = _model_name.to_s.safe_constantize
+        fail "model could not be found for #{self.name}" if @model.nil?
+        @model
       end
 
       def _allowed_filter?(filter)

test/unit/resource/resource_test.rb

@@ -8,6 +8,9 @@ def self.records(options)
   end
 end
 
+class NoMatchResource < JSONAPI::Resource
+end
+
 class CatResource < JSONAPI::Resource
   attribute :id
   attribute :name
@@ -52,6 +55,14 @@ def test_model
     assert_equal(PostResource._model_class, Post)
   end
 
+  def test_nil_model_class
+    error = assert_raises(StandardError) { NoMatchResource._model_class }
+    assert_equal(
+      error.message,
+      "model could not be found for NoMatchResource"
+    )
+  end
+
   def test_model_alternate
     assert_equal(ArticleResource._model_class, Post)
   end