Use the name of a registry as its child spec id (#6560)

Author: yordis

lib/elixir/lib/registry.ex

@@ -304,7 +304,7 @@ defmodule Registry do
   @doc false
   def child_spec(opts) do
     %{
-      id: Registry,
+      id: Keyword.get(opts, :name, Registry),
       start: {Registry, :start_link, [opts]},
       type: :supervisor
     }

lib/elixir/test/elixir/registry_test.exs

@@ -521,6 +521,11 @@ defmodule RegistryTest do
     end
   end
 
+  test "child_spec/1 uses :name as :id" do
+    assert %{id: :custom_name} = Registry.child_spec([name: :custom_name])
+    assert %{id: Registry} = Registry.child_spec([])
+  end
+
   defp register_task(registry, key, value) do
     parent = self()
     {:ok, task} =