Start iterator with empty string

Author: jiegillet

lib/elixir_analyzer.ex

@@ -253,10 +253,9 @@ defmodule ElixirAnalyzer do
   defp read_files(paths) do
     Enum.reduce_while(
       paths,
-      {:ok, nil},
+      {:ok, ""},
       fn path, {:ok, code} ->
         case File.read(path) do
-          {:ok, file} when is_nil(code) -> {:cont, {:ok, file}}
           {:ok, file} -> {:cont, {:ok, code <> "\n" <> file}}
           {:error, err} -> {:halt, {:error, err}}
         end

test/elixir_analyzer/cli_test.exs

@@ -28,10 +28,10 @@ defmodule ElixirAnalyzer.CLITest do
          halted: false,
          source: %Source{
            code_ast: {:defmodule, _, _},
-           code_string: "defmodule Lasagna" <> _,
+           code_string: "\ndefmodule Lasagna" <> _,
            submitted_files: [@lasagna_path <> "/lib/lasagna.ex"],
            exemploid_ast: {:defmodule, _, _},
-           exemploid_string: "defmodule Lasagna" <> _,
+           exemploid_string: "\ndefmodule Lasagna" <> _,
            exemploid_files: [@lasagna_path <> "/.meta/exemplar.ex"],
            exercise_type: :concept,
            path: @lasagna_path,