Add deprecation warnings for old escript options

Author: alco

lib/mix/lib/mix/tasks/escriptize.ex

@@ -80,8 +80,31 @@ defmodule Mix.Tasks.Escriptize do
     escriptize(Mix.Project.config, opts[:force])
   end
 
+
+  @deprecated_opts [
+    :escript_main_module, :escript_name, :escript_path, :escript_app,
+    :escript_embed_elixir, :escript_embed_extra_apps, :escript_shebang,
+    :escript_comment, :escript_mu_args, ]
+
+  @prefix_len String.length("escript_")
+
+  defp collect_deprecated_opts(project) do
+    Enum.reduce(@deprecated_opts, [], fn name, acc ->
+      if Keyword.has_key?(project, name) do
+        IO.puts :stderr, "Option #{inspect name} is deprecated. " <>
+            "Use the new `:escript` option that takes a keyword list instead."
+        new_name =
+          Atom.to_string(name) |> String.slice(@prefix_len, 100) |> String.to_atom()
+        [{new_name, project[name]}|acc]
+      else
+        acc
+      end
+    end)
+  end
+
   defp escriptize(project, force) do
-    escript_opts = project[:escript]
+    escript_opts = project[:escript] || collect_deprecated_opts(project)
+
     script_name  = escript_opts[:name] || project[:app]
     filename     = escript_opts[:path] || Atom.to_string(script_name)
     main         = escript_opts[:main_module]