Return struct instead of multiple values

app/services/ci/register_build_service.rb

@@ -6,6 +6,8 @@ module Ci
 
     attr_reader :runner
 
+    Result = Struct.new(:build, :valid?)
+
     def initialize(runner)
       @runner = runner
     end
@@ -29,10 +31,10 @@ module Ci
         build.run!
       end
 
-      [build, true]
+      Result.new(build, true)
 
     rescue StateMachines::InvalidTransition, ActiveRecord::StaleObjectError
-      [nil, false]
+      Result.new(build, false)
     end
 
     private

lib/ci/api/builds.rb

@@ -24,14 +24,14 @@ module Ci
 
           new_update = current_runner.ensure_runner_queue_value
 
-          build, valid = Ci::RegisterBuildService.new(current_runner).execute
+          result = Ci::RegisterBuildService.new(current_runner).execute
 
-          if valid
-            if build
+          if result.valid?
+            if result.build
               Gitlab::Metrics.add_event(:build_found,
-                                        project: build.project.path_with_namespace)
+                                        project: result.build.project.path_with_namespace)
 
-              present build, with: Entities::BuildDetails
+              present result.build, with: Entities::BuildDetails
             else
               Gitlab::Metrics.add_event(:build_not_found)
 

spec/services/ci/register_build_service_spec.rb

@@ -171,7 +171,7 @@ module Ci
       end
 
       def execute(runner)
-        described_class.new(runner).execute.first
+        described_class.new(runner).execute.build
       end
     end
   end