Add a Testable submodule

test/unit/test_p256.ml

@@ -1,3 +1,19 @@
+module Testable = struct
+  let ok_or_error =
+    let pp ppf = function
+      | Ok () -> Format.fprintf ppf "ok"
+      | Error e -> Format.fprintf ppf "%a" Fiat_p256.pp_error e
+    in
+    let eq ra rb =
+      match (ra, rb) with
+      | Ok (), Ok () -> true
+      | Error (ea : Fiat_p256.error), Error eb -> ea = eb
+      | Ok _, Error _ -> false
+      | Error _, Ok _ -> false
+    in
+    Alcotest.testable pp eq
+end
+
 let key_pair_of_hex h = Fiat_p256.gen_key ~rng:(fun _ -> Hex.to_cstruct h)
 
 let scalar_of_hex h = fst (key_pair_of_hex h)
@@ -109,23 +125,11 @@ let scalar_mult =
       ~expected:
         "48e82c9b82c88cb9fc2a5cff9e7c41bc4255ff6bd3814538c9b130877c07e4cf" ]
 
+let to_ok_or_error = function
+  | Ok _ -> Ok ()
+  | Error _ as e -> e
+
 let point_validation =
-  let pp ppf = function
-    | Ok () -> Format.fprintf ppf "ok"
-    | Error e -> Format.fprintf ppf "%a" Fiat_p256.pp_error e
-  in
-  let eq ra rb =
-    match (ra, rb) with
-    | Ok (), Ok () -> true
-    | Error (ea : Fiat_p256.error), Error eb -> ea = eb
-    | Ok _, Error _ -> false
-    | Error _, Ok _ -> false
-  in
-  let to_result = function
-    | Ok _ -> Ok ()
-    | Error _ as e -> e
-  in
-  let testable = Alcotest.testable pp eq in
   let test ~name ~x ~y ~expected =
     let scalar =
       scalar_of_hex
@@ -139,8 +143,8 @@ let point_validation =
     , `Quick
     , fun () ->
         Fiat_p256.key_exchange scalar point
-        |> to_result
-        |> Alcotest.check testable __LOC__ expected )
+        |> to_ok_or_error
+        |> Alcotest.check Testable.ok_or_error __LOC__ expected )
   in
   let zero = `Hex (String.make 64 '0') in
   let sb =