5 files changed, 46 insertions, 13 deletions
diff --git a/app/graphql/resolvers/base_resolver.rb b/app/graphql/resolvers/base_resolver.rb
index 539e37db1c2..5db618254cb 100644
--- a/app/graphql/resolvers/base_resolver.rb
+++ b/app/graphql/resolvers/base_resolver.rb
@@ -118,7 +118,7 @@ module Resolvers
     end
 
     def offset_pagination(relation)
-      ::Gitlab::Graphql::Pagination::OffsetActiveRecordRelationConnection.new(relation)
+      ::Gitlab::Graphql::Pagination::OffsetPaginatedRelation.new(relation)
     end
 
     override :object
diff --git a/app/graphql/resolvers/package_details_resolver.rb b/app/graphql/resolvers/package_details_resolver.rb
index dcf4430e55f..e688e34599a 100644
--- a/app/graphql/resolvers/package_details_resolver.rb
+++ b/app/graphql/resolvers/package_details_resolver.rb
@@ -1,9 +1,9 @@
 # frozen_string_literal: true
 
 module Resolvers
-  # No return types defined because they can be different.
-  # rubocop: disable Graphql/ResolverType
   class PackageDetailsResolver < BaseResolver
+    type ::Types::Packages::PackageType, null: true
+
     argument :id, ::Types::GlobalIDType[::Packages::Package],
       required: true,
       description: 'The global ID of the package.'
diff --git a/app/graphql/resolvers/packages_resolver.rb b/app/graphql/resolvers/packages_resolver.rb
index d19099e94d4..3eeed48ff7e 100644
--- a/app/graphql/resolvers/packages_resolver.rb
+++ b/app/graphql/resolvers/packages_resolver.rb
@@ -2,7 +2,7 @@
 
 module Resolvers
   class PackagesResolver < BaseResolver
-    type Types::Packages::PackageType, null: true
+    type Types::Packages::PackageType.connection_type, null: true
 
     def resolve(**args)
       return unless packages_available?
diff --git a/app/graphql/resolvers/project_merge_requests_resolver.rb b/app/graphql/resolvers/project_merge_requests_resolver.rb
index 830649d5e52..21d9afc31ab 100644
--- a/app/graphql/resolvers/project_merge_requests_resolver.rb
+++ b/app/graphql/resolvers/project_merge_requests_resolver.rb
@@ -6,5 +6,38 @@ module Resolvers
     accept_assignee
     accept_author
     accept_reviewer
+
+    def resolve(**args)
+      scope = super
+
+      if only_count_is_selected_with_merged_at_filter?(args) && Feature.enabled?(:optimized_merge_request_count_with_merged_at_filter)
+        MergeRequest::MetricsFinder
+          .new(current_user, args.merge(target_project: project))
+          .execute
+      else
+        scope
+      end
+    end
+
+    def only_count_is_selected_with_merged_at_filter?(args)
+      return unless lookahead
+
+      argument_names = args.except(:lookahead, :sort, :merged_before, :merged_after).keys
+
+      # no extra filtering arguments are provided
+      return unless argument_names.empty?
+      return unless args[:merged_after] || args[:merged_before]
+
+      # Detecting a specific query pattern:
+      # mergeRequests(mergedAfter: "X", mergedBefore: "Y") {
+      #   count
+      #   totalTimeToMerge
+      # }
+      allowed_selected_fields = [:count, :total_time_to_merge]
+      selected_fields = lookahead.selections.map(&:field).map(&:original_name)
+
+      # only the allowed_selected_fields are present
+      (selected_fields - allowed_selected_fields).empty?
+    end
   end
 end
diff --git a/app/graphql/resolvers/terraform/states_resolver.rb b/app/graphql/resolvers/terraform/states_resolver.rb
index 38b26a948b1..f543eb182e8 100644
--- a/app/graphql/resolvers/terraform/states_resolver.rb
+++ b/app/graphql/resolvers/terraform/states_resolver.rb
@@ -3,20 +3,20 @@
 module Resolvers
   module Terraform
     class StatesResolver < BaseResolver
-      type Types::Terraform::StateType, null: true
+      type Types::Terraform::StateType.connection_type, null: true
 
       alias_method :project, :object
 
-      def resolve(**args)
-        return ::Terraform::State.none unless can_read_terraform_states?
-
-        project.terraform_states.ordered_by_name
+      when_single do
+        argument :name, GraphQL::STRING_TYPE,
+            required: true,
+            description: 'Name of the Terraform state.'
       end
 
-      private
-
-      def can_read_terraform_states?
-        current_user.can?(:read_terraform_state, project)
+      def resolve(**args)
+        ::Terraform::StatesFinder
+          .new(project, current_user, params: args)
+          .execute
       end
     end
   end