Fix autocompletion on Erlang/OTP 26, closes #13307

Author: josevalim

lib/iex/lib/iex/autocomplete.ex

@@ -197,9 +197,7 @@ defmodule IEx.Autocomplete do
   end
 
   defp expand_signatures([_ | _] = signatures, _shell) do
-    [head | tail] = Enum.sort(signatures, &(String.length(&1) <= String.length(&2)))
-    if tail != [], do: IO.write("\n" <> (tail |> Enum.reverse() |> Enum.join("\n")))
-    yes("", [head])
+    yes("", Enum.sort_by(signatures, &String.length/1))
   end
 
   defp expand_signatures([], shell), do: expand_local_or_var("", shell)

lib/iex/test/iex/autocomplete_test.exs

@@ -492,11 +492,8 @@ defmodule IEx.AutocompleteTest do
 
     eval("import Enum; import Protocol")
 
-    assert ExUnit.CaptureIO.capture_io(fn ->
-             send(self(), expand(~c"reduce("))
-           end) == "\nreduce(enumerable, acc, fun)"
-
-    assert_received {:yes, ~c"", [~c"reduce(enumerable, fun)"]}
+    assert expand(~c"reduce(") ==
+             {:yes, ~c"", [~c"reduce(enumerable, fun)", ~c"reduce(enumerable, acc, fun)"]}
 
     assert expand(~c"take(") == {:yes, ~c"", [~c"take(enumerable, amount)"]}
     assert expand(~c"derive(") == {:yes, ~c"", [~c"derive(protocol, module, options \\\\ [])"]}