http: Use or_error for method_of_string

Author: anuragsoni

http/src/meth.ml

@@ -21,16 +21,16 @@ include T
 include Comparable.Make (T)
 
 let of_string = function
-  | "GET" -> Some `GET
-  | "HEAD" -> Some `HEAD
-  | "POST" -> Some `POST
-  | "PUT" -> Some `PUT
-  | "DELETE" -> Some `DELETE
-  | "CONNECT" -> Some `CONNECT
-  | "OPTIONS" -> Some `OPTIONS
-  | "TRACE" -> Some `TRACE
-  | "PATCH" -> Some `PATCH
-  | _ -> None
+  | "GET" -> Ok `GET
+  | "HEAD" -> Ok `HEAD
+  | "POST" -> Ok `POST
+  | "PUT" -> Ok `PUT
+  | "DELETE" -> Ok `DELETE
+  | "CONNECT" -> Ok `CONNECT
+  | "OPTIONS" -> Ok `OPTIONS
+  | "TRACE" -> Ok `TRACE
+  | "PATCH" -> Ok `PATCH
+  | meth -> Or_error.error "Invalid HTTP method" meth sexp_of_string
 ;;
 
 let to_string = function

http/src/meth.mli

@@ -17,7 +17,7 @@ type t =
   ]
 [@@deriving sexp, compare, hash, enumerate, quickcheck]
 
-val of_string : string -> t option
+val of_string : string -> t Or_error.t
 val to_string : t -> string
 
 (** [is_safe t] returns true if the semantics for a HTTP method are essentially read-only,

http/test/test_method.ml

@@ -6,14 +6,14 @@ let%test_unit "Http Methods can be coverted to strings and back" =
   let b =
     a
     |> List.map ~f:Meth.to_string
-    |> List.map ~f:(fun v -> Option.value_exn (Meth.of_string v))
+    |> List.map ~f:(fun v -> Or_error.ok_exn (Meth.of_string v))
   in
   [%test_result: Meth.t list] ~expect:a b
 ;;
 
 let%test_unit "Meth.of_string (Meth.to_string m) is never none" =
   Quickcheck.test ~sexp_of:[%sexp_of: Meth.t] Meth.quickcheck_generator ~f:(fun meth ->
-    [%test_result: Meth.t option]
-      ~expect:(Some meth)
+    [%test_result: Meth.t Or_error.t]
+      ~expect:(Ok meth)
       (Meth.of_string (Meth.to_string meth)))
 ;;