Assert the results of all koans tests

test/test_helper.exs

@@ -1,11 +1,14 @@
 ExUnit.start()
 
 defmodule TestHarness do
+  import ExUnit.Assertions
+
   def test_all(module, answers) do
     module.all_koans
     |> check_answer_count(answers, module)
     |> Enum.zip(answers)
     |> run_all(module)
+    |> check_results
   end
 
   defp check_answer_count(koans, answers, module) do
@@ -19,6 +22,10 @@ defmodule TestHarness do
     end
   end
 
+  defp check_results(results) do
+    Enum.each results, &(assert &1 == :passed)
+  end
+
   def run_all(pairs, module) do
     Enum.map(pairs, fn ({koan, answer}) -> Execute.run_koan(module, koan, [answer]) end)
   end