Do not leak EXIT messages on Registry dispatch

Signed-off-by: José Valim <[email protected]>

Author: José Valim

lib/elixir/lib/registry.ex

@@ -359,11 +359,13 @@ defmodule Registry do
   end
   defp dispatch_task(registry, key, mfa_or_fun, partition) do
     partition = partition - 1
+    parent = self()
     task = Task.async(fn ->
       registry
       |> key_ets!(partition)
       |> safe_lookup_second(key)
       |> apply_non_empty_to_mfa_or_fun(mfa_or_fun)
+      Process.unlink(parent)
       :ok
     end)
     [task | dispatch_task(registry, key, mfa_or_fun, partition)]

lib/elixir/test/elixir/registry_test.exs

@@ -207,6 +207,8 @@ defmodule RegistryTest do
       end
 
       test "dispatches to multiple keys", %{registry: registry} do
+        Process.flag(:trap_exit, true)
+
         assert Registry.dispatch(registry, "hello", fn _ ->
           raise "will never be invoked"
         end) == :ok
@@ -230,6 +232,8 @@ defmodule RegistryTest do
         refute_received {:dispatch, :value1}
         refute_received {:dispatch, :value2}
         assert_received {:dispatch, :value3}
+
+        refute_received {:EXIT, _, _}
       end
 
       test "allows process unregistering", %{registry: registry} do