   # Read and strip the version from the VERSION file.
   defmacrop get_version do
     case read_stripped(@version_file) do
-      ""   -> raise RuntimeError, message: "could not read the version number from VERSION"
+      "" -> raise RuntimeError, message: "could not read the version number from VERSION"
       data -> data
     end
   end

  The returned value is a map containing name-value pairs.
  Variable names and their values are strings.
  """
  @spec get_env() :: %{optional(String.t) => String.t}
  def get_env do
    Enum.into(:os.getenv, %{}, fn var ->
      var = IO.chardata_to_string var
      [k, v] = String.split var, "=", parts: 2
      {k, v}
    end)
  end

    do: cmd_opts(t, [{:env, validate_env(enum)} | opts], into)

  defp cmd_opts([{key, val} | _], _opts, _into),
    do: raise(ArgumentError, "invalid option #{inspect(key)} with value #{inspect(val)}")

  defp cmd_opts([], opts, into), do: {into, opts}

  defp validate_env(enum) do
    Enum.map(enum, fn
      {k, nil} ->
        {String.to_charlist(k), false}

      {k, v} ->
        {String.to_charlist(k), String.to_charlist(v)}

      other ->
        raise ArgumentError, "invalid environment key-value #{inspect(other)}"
    end)
  end

  @doc """
