Make `Ci::Group` to be efficient

app/models/ci/group.rb

@@ -9,6 +9,7 @@ module Ci
   #
   class Group
     include StaticModel
+    include Gitlab::Utils::StrongMemoize
 
     attr_reader :stage, :name, :jobs
 
@@ -21,7 +22,11 @@ module Ci
     end
 
     def status
-      @status ||= commit_statuses.status
+      strong_memoize(:status) do
+        Gitlab::Ci::Status::GroupedStatuses
+          .new(@jobs)
+          .one[:status]
+      end
     end
 
     def detailed_status(current_user)

app/models/concerns/has_status.rb

@@ -21,7 +21,7 @@ module HasStatus
     def status
       Gitlab::Ci::Status::GroupedStatuses
         .new(all)
-        .one&.dig(:status)
+        .one[:status]
     end
 
     def started_at

app/services/ci/process_pipeline_service.rb

@@ -2,6 +2,8 @@
 
 module Ci
   class ProcessPipelineService < BaseService
+    include Gitlab::Utils::StrongMemoize
+
     attr_reader :pipeline
 
     def execute(pipeline, trigger_build_ids = nil)

lib/gitlab/ci/status/grouped_statuses.rb

@@ -12,8 +12,11 @@ module Gitlab
         def one(**query)
           validate_keys!(query.keys)
 
-          item_hash = find_one(data_hash, query)
-          status_for_key(query, item_hash) if item_hash
+          if item_hash = find_one(data_hash, query)
+            status_for_key(query, item_hash)
+          else
+            {}
+          end
         end
 
         def group(*keys)