Fix Elixir 1.20 compilation warnings

.tool-versions

@@ -0,0 +1,2 @@
+elixir 1.20.0-rc.6
+erlang 27.3.3

lib/gettext.ex

@@ -804,15 +804,10 @@ defmodule Gettext do
   @doc since: "1.0.0"
   @spec put_locale!(backend, locale) :: locale | nil
   def put_locale!(backend, locale) when is_binary(locale) do
-    cond do
-      not is_binary(locale) ->
-        raise ArgumentError, "put_locale/2 only accepts binary locales, got: #{inspect(locale)}"
-
-      locale in known_locales(backend) ->
-        put_locale(backend, locale)
-
-      true ->
-        raise ArgumentError, "put_locale!/2 only support known locales, got: #{inspect(locale)}"
+    if locale in known_locales(backend) do
+      put_locale(backend, locale)
+    else
+      raise ArgumentError, "put_locale!/2 only support known locales, got: #{inspect(locale)}"
     end
   end
 

lib/gettext/compiler.ex

@@ -423,7 +423,7 @@ defmodule Gettext.Compiler do
           :parallel ->
             grouped
             |> Enum.map(fn {module, files} ->
-              Kernel.ParallelCompiler.async(fn ->
+              Task.async(fn ->
                 compile_split_po_files(env, module, files, plural_mod, opts[:interpolation])
               end)
             end)

lib/gettext/extractor.ex

@@ -388,11 +388,6 @@ defmodule Gettext.Extractor do
     end
   end
 
-  defp ensure_empty_msgstr!(%Message.Plural{} = message) do
-    raise Error,
-          "plural message with msgid '#{IO.iodata_to_binary(message.msgid)}' has a non-empty msgstr"
-  end
-
   defp blank?(str) when not is_nil(str), do: IO.iodata_length(str) == 0
   defp blank?(_), do: true