Improve Binary.Inspect for Function test

Author: yrashk

lib/elixir/test/elixir/binary/inspect_test.exs

@@ -188,6 +188,10 @@ end
 defmodule Binary.Inspect.FunctionTest do
   use ExUnit.Case, async: true
 
+  def f do
+    fn() -> :ok end
+  end
+
   test :funs do
     bin = inspect(fn(x) -> x + 1 end)
     assert '#Fun<' ++ _ = binary_to_list(bin)
@@ -198,6 +202,11 @@ defmodule Binary.Inspect.FunctionTest do
     assert bin == "function(Enum.map/2)"
   end
 
+  test :external_elixir_fun do
+    bin = inspect(f)
+    assert '#Fun<' ++ _ = binary_to_list(bin)
+  end
+
   test :external_erlang do
     bin = inspect(function(:lists.map/2))
     assert bin == "function(:lists.map/2)"