Make sure the given module is loaded before trying reload it.

Author: Ricardo de Cillo

lib/iex/lib/iex/helpers.ex

@@ -308,8 +308,8 @@ defmodule IEx.Helpers do
   end
 
   defp do_r(module) do
-    unless :code.is_loaded(module) do
-      raise ArgumentError, message: "Unloaded module #{module}. Try loading the module's beam file with `IEx.Helpers.l\\1`"
+    unless Code.ensure_loaded?(module) do
+      raise ArgumentError, message: "The module is not loaded and it could not be found"
     end
 
     source = source(module)

lib/iex/test/iex/helpers_test.exs

@@ -305,7 +305,7 @@ defmodule IEx.HelpersTest do
   end
 
   test "r helper unavailable" do
-    assert_raise ArgumentError, "Unloaded module non_existent_module. Try loading the module's beam file with `IEx.Helpers.l\\1`", fn ->
+    assert_raise ArgumentError, "The module is not loaded and it could not be found", fn ->
       r :non_existent_module
     end
   end