mix_helpers.exs

# Get Mix output sent to the current
# process to avoid polluting tests.
Mix.shell(Mix.Shell.Process)

defmodule MixHelper do
  import ExUnit.Assertions

  def tmp_path do
    Path.expand("../../tmp", __DIR__)
  end

  def in_tmp(which, function) do
    path = Path.join(tmp_path(), which)
    File.rm_rf!(path)
    File.mkdir_p!(path)
    File.cd!(path, function)
  end

  def assert_file(file) do
    assert File.regular?(file), "Expected #{file} to exist, but does not"
  end

  def refute_file(file) do
    refute File.regular?(file), "Expected #{file} to not exist, but it does"
  end

  def assert_file(file, match) do
    cond do
      is_list(match) ->
        assert_file(file, &Enum.each(match, fn m -> assert &1 =~ m end))

      is_binary(match) or is_struct(match, Regex) ->
        assert_file(file, &assert(&1 =~ match))

      is_function(match, 1) ->
        assert_file(file)
        match.(File.read!(file))
    end
  end

  def with_generator_env(new_env, fun) do
    old = Application.get_env(:phoenix, :generators)
    Application.put_env(:phoenix, :generators, new_env)

    try do
      fun.()
    after
      Application.put_env(:phoenix, :generators, old)
    end
  end
end