keep track of lost transfers on ranked choice irv

makerdao · Sep 12, 2020 · 1aedb4e · 1aedb4e
1 parent 3bd5952
commit 1aedb4e
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/packages/dai-plugin-governance/src/GovPollingService.js b/packages/dai-plugin-governance/src/GovPollingService.js
@@ -301,7 +301,6 @@ export default class GovPollingService extends PrivateService {
       });
 
       tally.options[optionToEliminate].eliminated = true;
-      tally.options[optionToEliminate].transfer = BigNumber(0);
 
       // a vote needs to be moved if...
       // 1) it's currently for the eliminated candidate
@@ -313,12 +312,18 @@ export default class GovPollingService extends PrivateService {
 
       // move votes to the next choice on their preference list
       votesToBeMoved.forEach(vote => {
+        const prevChoice = votes[vote.index].choice;
         votes[vote.index].choice = votes[vote.index].ballot.pop();
         if (!tally.options[votes[vote.index].choice])
           tally.options[votes[vote.index].choice] = { ...defaultOptionObj };
+
         tally.options[votes[vote.index].choice].transfer = BigNumber(
           tally.options[votes[vote.index].choice].transfer
         ).plus(vote.mkrSupport || 0);
+
+        tally.options[prevChoice].transfer = BigNumber(
+          tally.options[prevChoice].transfer
+        ).minus(vote.mkrSupport || 0);
       });
 
       // look for a candidate with the majority

diff --git a/packages/dai-plugin-governance/test/fixtures.js b/packages/dai-plugin-governance/test/fixtures.js
@@ -163,7 +163,7 @@ export const dummyBallotNoMajorityExpect = {
   options: {
     '1': {
       firstChoice: '60.025',
-      transfer: '0',
+      transfer: '-60.025',
       winner: false,
       eliminated: true
     },
@@ -210,7 +210,7 @@ export const dummyBallotMultipleRoundsExpect = {
   options: {
     '1': {
       firstChoice: '60.025',
-      transfer: '0',
+      transfer: '-56.025',
       winner: false,
       eliminated: true
     },
@@ -228,7 +228,7 @@ export const dummyBallotMultipleRoundsExpect = {
     },
     '4': {
       firstChoice: '4',
-      transfer: '0',
+      transfer: '-4',
       winner: false,
       eliminated: true
     }