Alpha/Vote: fix proposal voting to be stake propotional

Co-authored-by: Jun FURUSE <jun.furuse@dailambda.jp>
Co-authored-by: Marco Stronati <marco@stronati.org>

src/proto_alpha/lib_protocol/src/alpha_context.mli

@@ -733,7 +733,7 @@ module Vote : sig
     context -> Protocol_hash.t -> public_key_hash ->
     context Lwt.t
   val get_proposals:
-    context -> int32 Protocol_hash.Map.t Lwt.t
+    context -> int32 Protocol_hash.Map.t tzresult Lwt.t
   val clear_proposals: context -> context Lwt.t
 
   val listings_encoding : (Signature.Public_key_hash.t * int32) list Data_encoding.t

src/proto_alpha/lib_protocol/src/amendment.ml

@@ -67,7 +67,7 @@ let check_approval_and_update_quorum ctxt =
 let start_new_voting_cycle ctxt =
   Vote.get_current_period_kind ctxt >>=? function
   | Proposal -> begin
-      Vote.get_proposals ctxt >>= fun proposals ->
+      Vote.get_proposals ctxt >>=? fun proposals ->
       Vote.clear_proposals ctxt >>= fun ctxt ->
       Vote.clear_listings ctxt >>=? fun ctxt ->
       match select_winning_proposal proposals with

src/proto_alpha/lib_protocol/src/vote_storage.ml

@@ -28,13 +28,18 @@ let record_proposal ctxt delegate proposal =
 
 let get_proposals ctxt =
   Storage.Vote.Proposals.fold ctxt
-    ~init:Protocol_hash.Map.empty
-    ~f:(fun (proposal, _delegate) acc ->
-        let previous =
-          match Protocol_hash.Map.find_opt proposal acc with
-          | None -> 0l
-          | Some x -> x in
-        Lwt.return (Protocol_hash.Map.add proposal (Int32.succ previous) acc))
+    ~init:(ok Protocol_hash.Map.empty)
+    ~f:(fun (proposal, delegate) acc ->
+        (* Assuming the same listings is used at votings *)
+        Storage.Vote.Listings.get ctxt delegate >>=? fun weight ->
+        Lwt.return begin acc >>? fun acc ->
+          let previous =
+            match Protocol_hash.Map.find_opt proposal acc with
+            | None -> 0l
+            | Some x -> x
+          in
+          ok (Protocol_hash.Map.add proposal (Int32.add weight previous) acc)
+        end)
 
 let clear_proposals ctxt =
   Storage.Vote.Proposals.clear ctxt
@@ -60,6 +65,7 @@ let record_ballot = Storage.Vote.Ballots.init_set
 let get_ballots ctxt =
   Storage.Vote.Ballots.fold ctxt
     ~f:(fun delegate ballot (ballots: ballots tzresult) ->
+        (* Assuming the same listings is used at votings *)
         Storage.Vote.Listings.get ctxt delegate >>=? fun weight ->
         let count = Int32.add weight in
         Lwt.return begin

src/proto_alpha/lib_protocol/src/vote_storage.mli

@@ -28,7 +28,7 @@ val record_proposal:
   Raw_context.t Lwt.t
 
 val get_proposals:
-  Raw_context.t -> int32 Protocol_hash.Map.t Lwt.t
+  Raw_context.t -> int32 Protocol_hash.Map.t tzresult Lwt.t
 
 val clear_proposals: Raw_context.t -> Raw_context.t Lwt.t
 

src/proto_alpha/lib_protocol/src/voting_services.ml

@@ -101,7 +101,7 @@ let register () =
   end;
 
   register0 S.proposals begin fun ctxt () () ->
-    Vote.get_proposals ctxt >|= ok
+    Vote.get_proposals ctxt
   end;
 
   register0 S.listings begin fun ctxt () () ->