Change ordering of hashes in pretty_ballots page

src/lib/common.ml

@@ -150,4 +150,19 @@ let save_to filename writer x =
   Bi_outbuf.flush_channel_writer ob;
   close_out oc;;
 
+let b64_order = "+/0123456789aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ"
+
+let compare_b64 a b =
+  let na = String.length a and nb = String.length b in
+  let value_of c = try String.index b64_order c with Not_found -> -1 in
+  let rec loop i =
+    match (i < na), (i < nb) with
+    | true, true ->
+       let diff = value_of a.[i] - value_of b.[i] in
+       if diff = 0 then loop (i+1) else diff
+    | true, false -> 1
+    | false, true -> -1
+    | false, false -> 0
+  in loop 0
+
 module SMap = Map.Make(String)

src/lib/common.mli

@@ -53,4 +53,6 @@ val option_map : ('a -> 'b) -> 'a option -> 'b option
 
 val save_to : string -> (Bi_outbuf.t -> 'a -> unit) -> 'a -> unit
 
+val compare_b64 : string -> string -> int
+
 module SMap : Map.S with type key = string

src/web/web_templates.ml

@@ -1645,9 +1645,7 @@ let pretty_ballots w hashes result () =
   let params = W.election.e_params in
   let title = params.e_name ^ " — " ^ L.accepted_ballots in
   let nballots = ref 0 in
-  let hashes =
-    List.sort (fun a b -> String.(compare (uppercase a) (uppercase b))) hashes
-  in
+  let hashes = List.sort compare_b64 hashes in
   let ballots =
     List.map
       (fun h ->