Fix burndown negative count edge case

ee/app/assets/javascripts/burndown_chart/burndown_chart_data.js

@@ -53,7 +53,7 @@ export default class BurndownChartData {
       // weight count on an given date. To mitigate this, we reset the current
       // date's counters to 0 and carry forward the negative count to a future
       // date until the total is positive again.
-      if (openIssuesCount < 0 || openIssuesWeight < 0) {
+      if (openIssuesCount <= 0 || openIssuesWeight <= 0) {
         carriedIssuesCount = openIssuesCount;
         carriedIssuesWeight = openIssuesWeight;
 

ee/changelogs/unreleased/weimeng-fix-burndown-chart-reset-logic.yml

+---
+title: Fix burndown negative count edge case
+merge_request: 18053
+author:
+type: fixed

ee/spec/frontend/burndown_chart/burndown_chart_data_spec.js

@@ -93,6 +93,7 @@ describe('BurndownChartData', () => {
           { created_at: '2017-03-01T00:00:00.000Z', weight: 2, action: 'closed' },
           { created_at: '2017-03-01T00:00:00.000Z', weight: 2, action: 'closed' },
           { created_at: '2017-03-01T00:00:00.000Z', weight: 2, action: 'closed' },
+          { created_at: '2017-03-02T00:00:00.000Z', weight: 2, action: 'created' },
         );
       });
 
@@ -100,7 +101,7 @@ describe('BurndownChartData', () => {
         expect(burndownChartData.generate()).toEqual([
           ['2017-03-01', 0, 0],
           ['2017-03-02', 0, 0],
-          ['2017-03-03', 1, 2],
+          ['2017-03-03', 2, 4],
         ]);
       });
     });