Replace downcase with underscore for multi-word roots

CHANGELOG.md

@@ -14,6 +14,7 @@
 * [#758](https://github.com/ruby-grape/grape-swagger/pull/758): Handle cases where a route's prefix is a nested URL - [@SimonKaluza](https://github.com/simonkaluza).
 * [#757](https://github.com/ruby-grape/grape-swagger/pull/757): Fix `array_use_braces` for nested body params - [@bikolya](https://github.com/bikolya).
 * [#756](https://github.com/ruby-grape/grape-swagger/pull/756): Fix reference creation when custom type for documentation is provided - [@bikolya](https://github.com/bikolya).
+* [#764](https://github.com/ruby-grape/grape-swagger/pull/764): Fix root element for multi-word entities - [@bikolya](https://github.com/bikolya).
 
 ### 0.33.0 (June 21, 2019)
 

lib/grape-swagger/endpoint.rb

@@ -271,7 +271,8 @@ def build_reference(route, value, response_model, settings)
     end
 
     def build_root(route, reference, response_model, settings)
-      default_root = route.options[:is_array] ? response_model.downcase.pluralize : response_model.downcase
+      default_root = response_model.underscore
+      default_root = default_root.pluralize if route.options[:is_array]
       case route.settings.dig(:swagger, :root)
       when true
         { type: 'object', properties: { default_root => reference } }

spec/lib/optional_object_spec.rb

@@ -39,7 +39,6 @@
       let(:options) do
         { host: proc { |request| request.host =~ /^example/ ? '/api-example' : '/api' } }
       end
-
       specify do
         expect(subject.build(key, options, request)).to eql '/api-example'
       end

spec/swagger_v2/api_swagger_v2_response_with_root_spec.rb

@@ -30,6 +30,13 @@ class ResponseApiWithRoot < Grape::API
           { 'declared_params' => declared(params) }
         end
 
+        route_setting :swagger, root: true
+        desc 'This returns underscored root',
+             http_codes: [{ code: 200, model: Entities::ApiError }]
+        get '/response_with_root_underscore' do
+          { 'declared_params' => declared(params) }
+        end
+
         route_setting :swagger, root: true
         desc 'This returns something',
              is_array: true,
@@ -97,6 +104,21 @@ def app
     end
   end
 
+  describe 'GET /response_with_root_underscore' do
+    subject do
+      get '/swagger_doc/response_with_root_underscore'
+      JSON.parse(last_response.body)
+    end
+
+    it 'adds root to the response' do
+      schema = subject.dig('paths', '/response_with_root_underscore', 'get', 'responses', '200', 'schema')
+      expect(schema).to eq(
+        'type' => 'object',
+        'properties' => { 'api_error' => { '$ref' => '#/definitions/ApiError' } }
+      )
+    end
+  end
+
   describe 'GET /response_with_array_and_root' do
     subject do
       get '/swagger_doc/response_with_array_and_root'