added refs_controller_spec

spec/controllers/projects/refs_controller_spec.rb

@@ -19,16 +19,19 @@ describe Projects::RefsController do
           format: format
     end
 
-    def xhr_get(format = :html)
+    def xhr_get(format = :html, path = 'foo/bar/baz.html')
       xhr :get,
           :logs_tree,
           namespace_id: project.namespace.to_param,
-          project_id: project, id: 'master',
-          path: 'foo/bar/baz.html', format: format
+          project_id: project,
+          id: 'master',
+          path: path,
+          format: format
     end
 
     it 'never throws MissingTemplate' do
       expect { default_get }.not_to raise_error
+      expect { xhr_get(:json) }.not_to raise_error
       expect { xhr_get }.not_to raise_error
     end
 
@@ -42,5 +45,14 @@ describe Projects::RefsController do
       xhr_get(:js)
       expect(response).to be_success
     end
+
+    it 'renders JSON' do
+      xhr_get(:json, '/')
+
+      expect(response).to be_success
+      expect(json_response).to be_kind_of(Array)
+      expect(json_response[0]['type']).to eq('tree')
+      expect(json_response[0]['file_name']).to eq('bar')
+    end
   end
 end