tests.sml

fun run_tests _ [] = []
  | run_tests f (x :: xs) =
      let
        fun aux { description, is_correct } =
          let
            val expl = description ^ ": " ^
              (if is_correct then "PASSED" else "FAILED") ^ "\n"
          in
            (print (expl); is_correct)
          end
      in
        (aux x) :: run_tests f xs
      end

fun evaluateList f { description, input, expected } =
  { description = description, is_correct = (f input) = expected }

fun evaluateAllergicTo f { description, input, allergen, expected } =
  { description = description, is_correct = (f input allergen) = expected }

val testResults = run_tests list (List.map (evaluateList list) (#list test_cases))
  @ run_tests list (List.map (evaluateAllergicTo allergic_to) (#allergic_to test_cases));
val passedTests = List.filter (fn x => x) testResults;
val failedTests = List.filter (fn x => not x) testResults;