1 files changed, 41 insertions, 0 deletions
diff --git a/spec/support/graphql/subscriptions/action_cable/mock_gitlab_schema.rb b/spec/support/graphql/subscriptions/action_cable/mock_gitlab_schema.rb
new file mode 100644
index 00000000000..cd5d78cc78b
--- /dev/null
+++ b/spec/support/graphql/subscriptions/action_cable/mock_gitlab_schema.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+# A stub implementation of ActionCable.
+# Any methods to support the mock backend have `mock` in the name.
+module Graphql
+  module Subscriptions
+    module ActionCable
+      class MockGitlabSchema < GraphQL::Schema
+        class << self
+          def find_by_gid(gid)
+            return unless gid
+
+            if gid.model_class < ApplicationRecord
+              Gitlab::Graphql::Loaders::BatchModelLoader.new(gid.model_class, gid.model_id).find
+            elsif gid.model_class.respond_to?(:lazy_find)
+              gid.model_class.lazy_find(gid.model_id)
+            else
+              gid.find
+            end
+          end
+
+          def id_from_object(object, _type = nil, _ctx = nil)
+            unless object.respond_to?(:to_global_id)
+              # This is an error in our schema and needs to be solved. So raise a
+              # more meaningful error message
+              raise "#{object} does not implement `to_global_id`. " \
+                    "Include `GlobalID::Identification` into `#{object.class}"
+            end
+
+            object.to_global_id
+          end
+        end
+
+        query(::Types::QueryType)
+        subscription(::Types::SubscriptionType)
+
+        use GraphQL::Subscriptions::ActionCableSubscriptions, action_cable: MockActionCable, action_cable_coder: JSON
+      end
+    end
+  end
+end