unikernel/duniverse/base/test/test_sexpable.ml

@@ -0,0 +1,34 @@
+open! Import
+open Sexpable
+
+let%test_module "Of_stringable" =
+  (module struct
+    module Doubled_string = struct
+      (* Example module with a partial [of_string] function *)
+
+      type t = Double of string [@@deriving quickcheck]
+
+      include Of_stringable (struct
+        type nonrec t = t
+
+        let to_string (Double x) = x ^ x
+
+        let of_string x =
+          let length = String.length x in
+          let first_half = String.drop_suffix x (length / 2) in
+          let second_half = String.drop_suffix x (length / 2) in
+          if length % 2 = 0 && String.(first_half = second_half)
+          then Double first_half
+          else failwith [%string "Invalid doubled string %{x}"]
+        ;;
+      end)
+    end
+
+    let%expect_test "validate sexp grammar" =
+      require_ok
+        [%here]
+        (Sexp_grammar_validation.validate_grammar (module Doubled_string));
+      [%expect {| String |}]
+    ;;
+  end)
+;;