Properly convert `ISO_8859_1

src/metadataCharEncoding.ml

@@ -13,8 +13,6 @@ module Naive : T = struct
       | `UTF_16, `UTF_16
       | `UTF_16LE, `UTF_16LE
       | `UTF_16BE, `UTF_16BE
-      | `ISO_8859_1, _ ->
-          s
       | _ ->
           let buf = Buffer.create 10 in
           let len = String.length s in
@@ -26,32 +24,56 @@ module Naive : T = struct
           in
           let unicode_byte_length =
             match source with
-              | `ISO_8859_1 -> assert false
+              | `ISO_8859_1 -> fun _ -> 1
               | `UTF_8 -> Uchar.utf_8_byte_length
               | _ -> Uchar.utf_16_byte_length
           in
           let s, get_unicode_char =
             match source with
-              | `ISO_8859_1 -> assert false
-              | `UTF_8 -> (s, String.get_utf_8_uchar)
-              | `UTF_16BE -> (s, String.get_utf_16be_uchar)
-              | `UTF_16LE -> (s, String.get_utf_16le_uchar)
+              | `ISO_8859_1 -> (s, fun s pos -> Uchar.of_char s.[pos])
+              | `UTF_8 ->
+                  ( s,
+                    fun s pos ->
+                      Uchar.utf_decode_uchar (String.get_utf_8_uchar s pos) )
+              | `UTF_16BE ->
+                  ( s,
+                    fun s pos ->
+                      Uchar.utf_decode_uchar (String.get_utf_16be_uchar s pos)
+                  )
+              | `UTF_16LE ->
+                  ( s,
+                    fun s pos ->
+                      Uchar.utf_decode_uchar (String.get_utf_16le_uchar s pos)
+                  )
               | `UTF_16 ->
-                  let default = ("", String.get_utf_16be_uchar) in
+                  let default =
+                    ( "",
+                      fun s pos ->
+                        Uchar.utf_decode_uchar (String.get_utf_16be_uchar s pos)
+                    )
+                  in
                   if len < 2 then default
                   else (
                     let rem = String.sub s 2 (len - 2) in
                     match (s.[0], s.[1]) with
-                      | '\xfe', '\xff' -> (rem, String.get_utf_16be_uchar)
-                      | '\xff', '\xfe' -> (rem, String.get_utf_16le_uchar)
+                      | '\xfe', '\xff' ->
+                          ( rem,
+                            fun s pos ->
+                              Uchar.utf_decode_uchar
+                                (String.get_utf_16be_uchar s pos) )
+                      | '\xff', '\xfe' ->
+                          ( rem,
+                            fun s pos ->
+                              Uchar.utf_decode_uchar
+                                (String.get_utf_16le_uchar s pos) )
                       | _ -> default)
           in
           if target = `UTF_16 then add_unicode_char buf Uchar.bom;
           let len = String.length s in
           let rec f pos =
             if pos = len then Buffer.contents buf
             else (
-              let c = Uchar.utf_decode_uchar (get_unicode_char s pos) in
+              let c = get_unicode_char s pos in
               add_unicode_char buf c;
               f (pos + unicode_byte_length c))
           in

src/metadataID3v1.ml

@@ -9,10 +9,10 @@ let parse ?(recode = MetadataCharEncoding.Naive.convert) f : metadata =
   let size = match R.size f with Some n -> n | None -> raise Invalid in
   R.drop f (size - 128);
   if R.read f 3 <> "TAG" then raise Invalid;
-  let title = R.read f 30 |> trim |> recode in
-  let artist = R.read f 30 |> trim |> recode in
-  let album = R.read f 30 |> trim |> recode in
-  let year = R.read f 4 |> trim |> recode in
+  let title = R.read f 30 |> trim |> recode ~source:`ISO_8859_1 in
+  let artist = R.read f 30 |> trim |> recode ~source:`ISO_8859_1 in
+  let album = R.read f 30 |> trim |> recode ~source:`ISO_8859_1 in
+  let year = R.read f 4 |> trim |> recode ~source:`ISO_8859_1 in
   let comment = R.read f 30 in
   let comment, track, genre =
     if comment.[27] = '\000' then