Implemented ResultSingleOptional testkit request

Author: JuliaKovtun

testkit-backend/lib/testkit/backend/messages/requests/get_features.rb

@@ -19,7 +19,7 @@ class GetFeatures < Request
           'Feature:API:Result.List' => 'ja',
           'Feature:API:Result.Peek' => 'ja',
           'Feature:API:Result.Single' => 'ja',
-          'Feature:API:Result.SingleOptional' => '',
+          'Feature:API:Result.SingleOptional' => 'jar',
           'Feature:API:RetryableExceptions' => '',
           'Feature:API:Session:AuthConfig' => 'a',
           'Feature:API:Session:NotificationsConfig' => 'a',

testkit-backend/lib/testkit/backend/messages/requests/result_single_optional.rb

@@ -0,0 +1,15 @@
+module Testkit::Backend::Messages
+  module Requests
+    class ResultSingleOptional < Request
+      def process
+        result = fetch(result_id)
+        record = begin
+          { values: result.single.values.map(&method(:to_testkit)) }
+        rescue Neo4j::Driver::Exceptions::NoSuchRecordException
+          nil
+        end
+        named_entity('RecordOptional', record:, warnings: [])
+      end
+    end
+  end
+end

testkit-backend/lib/testkit/backend/messages/requests/start_test.rb

@@ -4,6 +4,8 @@ class StartTest < Request
       SKIPPED_TESTS = {
         'neo4j.test_direct_driver.TestDirectDriver.test_custom_resolver': 'Does not call resolver for direct connections', # skip for java hardcoded in testkit
         'stub.session_run_parameters.test_session_run_parameters.TestSessionRunParameters.test_empty_query': 'rejects empty string', # skip for java hardcoded in testkit
+        'stub.iteration.test_result_optional_single.TestResultSingleOptional.test_result_single_optional_with_2_records': 'Not implemented for ruby driver in testkit',
+        'stub.iteration.test_result_optional_single.TestResultSingleOptional.test_result_single_optional_with_disconnect': 'Not implemented for ruby driver in testkit',
         # 'stub.iteration.test_iteration_tx_run.TestIterationTxRun.test_nested': 'completely pulls the first query before running the second',
         # 'stub.optimizations.test_optimizations.TestOptimizations.test_uses_implicit_default_arguments': 'Driver does not implement optimization for qid in explicit transaction',
         # 'stub.optimizations.test_optimizations.TestOptimizations.test_uses_implicit_default_arguments_multi_query': 'Driver does not implement optimization for qid in explicit transaction',