Monitor pg scope before making test assertions

test/oban/notifiers/pg_test.exs

@@ -4,11 +4,21 @@ defmodule Oban.Notifiers.PGTest do
   alias Oban.Notifier
   alias Oban.Notifiers.PG
 
+  setup do
+    :pg.start_link(Oban.Notifiers.PG)
+    :pg.monitor_scope(Oban.Notifiers.PG)
+
+    :ok
+  end
+
   describe "namespacing" do
     test "namespacing by configured prefix without an override" do
       name_1 = start_supervised_oban!(notifier: PG, prefix: "pg_test")
       name_2 = start_supervised_oban!(notifier: PG, prefix: "pg_test")
 
+      assert_joined("pg_test")
+      assert_joined("pg_test")
+
       :ok = Notifier.listen(name_1, :signal)
       :ok = Notifier.notify(name_2, :signal, %{incoming: "message"})
 
@@ -19,10 +29,17 @@ defmodule Oban.Notifiers.PGTest do
       name_1 = start_supervised_oban!(notifier: {PG, namespace: :pg_test}, prefix: "pg_a")
       name_2 = start_supervised_oban!(notifier: {PG, namespace: :pg_test}, prefix: "pg_b")
 
+      assert_joined(:pg_test)
+      assert_joined(:pg_test)
+
       :ok = Notifier.listen(name_1, :signal)
       :ok = Notifier.notify(name_2, :signal, %{incoming: "message"})
 
       assert_receive {:notification, :signal, %{"incoming" => "message"}}
     end
   end
+
+  defp assert_joined(group) do
+      assert_receive {_ref, :join, ^group, _pids}
+  end
 end