return a default options obj with tally when no MKR support

packages/dai-plugin-governance/src/GovPollingService.ts

@@ -326,16 +326,27 @@ export default class GovPollingService extends PrivateService {
 
     const numVoters = currentVotes.length;
 
-    const resultsObject = currentVotes.reduce((acc, cur) => {
-      if (acc[cur.optionIdRaw]) {
-        acc[cur.optionIdRaw] = new BigNumber(acc[cur.optionIdRaw]).plus(
-          cur.mkrSupport
-        );
-      } else {
-        acc[cur.optionIdRaw] = new BigNumber(cur.mkrSupport);
-      }
-      return acc;
-    }, {});
+    // We assume all plurality votes have 3 options including abstain.
+    const pluralityDefaultOptions = {
+      '0': new BigNumber(0),
+      '1': new BigNumber(0),
+      '2': new BigNumber(0)
+    };
+
+    const resultsObject = currentVotes.reduce(
+      (acc, cur) => {
+        if (acc[cur.optionIdRaw]) {
+          acc[cur.optionIdRaw] = new BigNumber(acc[cur.optionIdRaw]).plus(
+            cur.mkrSupport
+          );
+        } else {
+          acc[cur.optionIdRaw] = new BigNumber(cur.mkrSupport);
+        }
+        return acc;
+      },
+      // Return a default state if currentVotes is empty.
+      pluralityDefaultOptions
+    );
 
     const summedSupport = Object.keys(resultsObject).map(option => ({
       optionId: option,

packages/dai-plugin-governance/test/GovPollingService.test.js

@@ -351,13 +351,50 @@ test('plurality tally', async () => {
       '1': {
         mkrSupport: '700',
         winner: true
+      },
+      '2': {
+        mkrSupport: '0',
+        winner: false
       }
     }
   };
 
   expect(JSON.parse(JSON.stringify(tally))).toEqual(expectedResult);
 });
 
+test('plurality tally with NO MKR support', async () => {
+  govPollingService._getPoll = jest.fn(() => ({
+    endDate: 123
+  }));
+
+  // Return an empty array when there is no support
+  govQueryApiService.getMkrSupportRankedChoice = jest.fn(() => []);
+
+  const tally = await govPollingService.getTallyPlurality();
+
+  const expectedResult = {
+    winner: '0',
+    totalMkrParticipation: '0',
+    numVoters: 0,
+    options: {
+      '0': {
+        mkrSupport: '0',
+        winner: true
+      },
+      '1': {
+        mkrSupport: '0',
+        winner: false
+      },
+      '2': {
+        mkrSupport: '0',
+        winner: false
+      }
+    }
+  };
+
+  expect(JSON.stringify(tally)).toEqual(JSON.stringify(expectedResult));
+});
+
 test('plurality tally with adjusted votes', async () => {
   govQueryApiService.getMkrSupportRankedChoice = jest.fn(
     () => dummyMkrGetMkrSupportRCForPluralityDataAdjusted