Improve task log based on @fishcakez feedback

Author: José Valim

lib/elixir/lib/process.ex

@@ -274,7 +274,7 @@ defmodule Process do
   already registered (check with `registered?/1`).
   """
   @spec register(pid | port, atom) :: true
-  def register(pid, name) do
+  def register(pid, name) when not name in [nil, false, true] do
     :erlang.register(name, pid)
   end
 

lib/elixir/lib/task/supervised.ex

@@ -69,19 +69,22 @@ defmodule Task.Supervised do
   end
 
   defp exit(info, mfa, reason) do
+    {fun, args} = get_running(mfa)
+
     :error_logger.format(
       "** Task ~p terminating~n" <>
       "** Started from ~p~n" <>
-      "** Running ~p~n" <>
+      "** When function  == ~p~n" <>
+      "**      arguments == ~p~n" <>
       "** Reason for termination == ~n" <>
-      "** ~p~n", [self, get_from(info), get_running(mfa), reason])
+      "** ~p~n", [self, get_from(info), fun, args, reason])
 
     exit(reason)
   end
 
   defp get_from({node, pid_or_name}) when node == node(), do: pid_or_name
   defp get_from(other), do: other
 
-  defp get_running({:erlang, :apply, [fun, []]}), do: fun
-  defp get_running(other), do: other
+  defp get_running({:erlang, :apply, [fun, []]}) when is_function(fun, 0), do: {fun, []}
+  defp get_running({mod, fun, args}), do: {:erlang.make_fun(mod, fun, length(args)), args}
 end