typing/Cmi_format: more informative magic error messages

gasche · gasche · commit 2212e4cf7746 · 2016-12-27T23:30:03.000-05:00
This commit changes the exported type Cmi_format.error.
diff --git a/typing/cmi_format.ml b/typing/cmi_format.ml
@@ -20,8 +20,7 @@ type pers_flags =
   | Unsafe_string
 
 type error =
-    Not_an_interface of string
-  | Wrong_version_interface of string * string
+    Not_an_interface of string * string option
   | Corrupted_interface of string
 
 exception Error of error
@@ -56,11 +55,11 @@ let read_cmi filename =
        with
        | End_of_file | Failure _ | Parse_error (Corrupted _) ->
            fail (Corrupted_interface filename)
-       | Parse_error (Not_a_magic_number _) | Unexpected (Kind _) ->
-           fail (Not_an_interface filename)
-       | Unexpected (Version (_cmi, { actual; expected })) ->
-           let msg = if actual < expected then "an older" else "a newer" in
-           fail (Wrong_version_interface (filename, msg))
+       | Parse_error (Not_a_magic_number _) ->
+           fail (Not_an_interface (filename, None))
+       | Unexpected error ->
+           let explanation = explain error in
+           fail (Not_an_interface (filename, Some explanation))
        end)
     (fun () -> close_in ic)
 
@@ -80,14 +79,20 @@ let output_cmi filename oc cmi =
 open Format
 
 let report_error ppf = function
-  | Not_an_interface filename ->
-      fprintf ppf "%a@ is not a compiled interface"
-        Location.print_filename filename
+  | Not_an_interface (filename, explanation) ->
+      fprintf ppf "%a@ is not a compiled interface."
+        Location.print_filename filename;
+      begin match explanation with
+      | None -> ()
+      | Some message -> fprintf ppf "\n%s" message
+      end
+(*
   | Wrong_version_interface (filename, older_newer) ->
       fprintf ppf
         "%a@ is not a compiled interface for this version of OCaml.@.\
          It seems to be for %s version of OCaml."
         Location.print_filename filename older_newer
+*)
   | Corrupted_interface filename ->
       fprintf ppf "Corrupted compiled interface@ %a"
         Location.print_filename filename
diff --git a/typing/cmi_format.mli b/typing/cmi_format.mli
@@ -38,8 +38,7 @@ val read_cmi : string -> cmi_infos
 (* Error report *)
 
 type error =
-    Not_an_interface of string
-  | Wrong_version_interface of string * string
+    Not_an_interface of string * string option
   | Corrupted_interface of string
 
 exception Error of error
diff --git a/typing/cmt_format.ml b/typing/cmt_format.ml
@@ -129,7 +129,7 @@ let read filename =
         in
         Some cmi, cmt
       else
-        raise(Cmi_format.Error(Cmi_format.Not_an_interface filename))
+        raise(Cmi_format.Error(Cmi_format.Not_an_interface (filename, None)))
     in
     close_in ic;
 (*    Printf.fprintf stderr "Cmt_format.read done\n%!"; *)
@@ -146,7 +146,7 @@ let read_cmt filename =
 let read_cmi filename =
   match read filename with
       None, _ ->
-        raise (Cmi_format.Error (Cmi_format.Not_an_interface filename))
+        raise (Cmi_format.Error (Cmi_format.Not_an_interface (filename, None)))
     | Some cmi, _ -> cmi
 
 let saved_types = ref []
