In my mix.exs I used to be able to call other Modules in order to fetch some configurations for my application-env configuration. Somehow this is not possible anymore since a few weeks (or the update to Elixir 1.11 maybe)

Here is an example of calling a module MyApp.Config.application_env() from inside my mix.exs file:

./mix.exs

defmodule MyApp.MixProject do
   use Mix.Project

     def project do
    [
      app: :my_app
      version: "0.2.0",
      elixir: "~> 1.5",
      elixirc_paths: elixirc_paths(Mix.env()),
      compilers: [:phoenix, :gettext] ++ Mix.compilers(),
      start_permanent: Mix.env() == :prod,
      aliases: aliases(),
      deps: deps(),
      test_paths: ["test", "lib"]
    ]
  end

  def application do
    [
      mod: {MyApp.Application, []},
      extra_applications: [:logger, :runtime_tools],
      env: MyApp.Config.application_env()
    ]
  end

  # Specifies which paths to compile per environment.
  defp elixirc_paths(:test), do: ["lib", "test/support"]
  defp elixirc_paths(_), do: ["lib"]

  # deps and aliases ....

./lib/config.ex

defmodule MyApp.Config do
  def application_env do
    [my_config: "foo", another_config: "bar"]
  end
end

Since the update to Elixir 1.11 I cannot call this module anymore since the compiler complains like this:

** (UndefinedFunctionError) function MyApp.Config.application_env/0 is undefined (module MyApp.Config is not available)
    MyApp.Config.application_env()
    mix.exs:28: MyApp.MixProject.application/0
    (mix 1.11.0) lib/mix/tasks/compile.app.ex:382: Mix.Tasks.Compile.App.project_apps/1
    (mix 1.11.0) lib/mix/tasks/compile.all.ex:97: Mix.Tasks.Compile.All.load_apps/2
    (mix 1.11.0) lib/mix/tasks/compile.all.ex:24: Mix.Tasks.Compile.All.run/1
    (mix 1.11.0) lib/mix/task.ex:394: Mix.Task.run_task/3
    (mix 1.11.0) lib/mix/tasks/compile.ex:119: Mix.Tasks.Compile.run/1
    (mix 1.11.0) lib/mix/task.ex:394: Mix.Task.run_task/3

I tried require-ing and import-ing the MyApp.Config module, but nothing helped. The config.ex file is compiled and put into the _build/dev/ebin folder, but somehow it is not available during compile-time. I also tried to set it to an module attribute like this: @config MyApp.Config, but even this didn’t help.

I have the feeling that it is related to the latest Compilation time improvements in 1.11 which states:

This change allows us to mark import s and require s as “exports dependencies” instead of “compile time” dependencies

Does somebody know how to make my MyApp.Config module available at compile-time again?