1 files changed, 48 insertions, 0 deletions

diff --git a/app/graphql/resolvers/issues/base_parent_resolver.rb b/app/graphql/resolvers/issues/base_parent_resolver.rb
new file mode 100644
index 00000000000..6308e56f049
--- /dev/null
+++ b/app/graphql/resolvers/issues/base_parent_resolver.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+module Resolvers
+  module Issues
+    class BaseParentResolver < Issues::BaseResolver
+      prepend ::Issues::LookAheadPreloads
+      include ::Issues::SortArguments
+
+      argument :state, Types::IssuableStateEnum,
+                required: false,
+                description: 'Current state of this issue.'
+
+      # see app/graphql/types/issue_connection.rb
+      type 'Types::IssueConnection', null: true
+
+      def resolve_with_lookahead(**args)
+        return Issue.none if resource_parent.nil?
+
+        finder = IssuesFinder.new(current_user, prepare_finder_params(args))
+
+        issues = Gitlab::Graphql::Loaders::IssuableLoader.new(resource_parent, finder).batching_find_all do |q|
+          apply_lookahead(q)
+        end
+
+        if non_stable_cursor_sort?(args[:sort])
+          # Certain complex sorts are not supported by the stable cursor pagination yet.
+          # In these cases, we use offset pagination, so we return the correct connection.
+          offset_pagination(issues)
+        else
+          issues
+        end
+      end
+
+      private
+
+      def resource_parent
+        # The project could have been loaded in batch by `BatchLoader`.
+        # At this point we need the `id` of the project to query for issues, so
+        # make sure it's loaded and not `nil` before continuing.
+        strong_memoize(:resource_parent) do
+          object.respond_to?(:sync) ? object.sync : object
+        end
+      end
+    end
+  end
+end
+
+Resolvers::Issues::BaseParentResolver.prepend_mod