Split sortEpics into assignDates method

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#9831 (closed)

ee/app/assets/javascripts/roadmap/utils/roadmap_utils.js

@@ -6,6 +6,8 @@ import {
   EXTEND_AS,
   TIMELINE_CELL_MIN_WIDTH,
   DAYS_IN_WEEK,
+  PAST_DATE,
+  FUTURE_DATE,
 } from '../constants';
 
 const monthsForQuarters = {
@@ -435,32 +437,17 @@ export function assignDates(a, b, { dateUndefined, outOfRange, originalDate, dat
 }
 
 export const sortEpics = (epics, sortedBy) => {
-  const pastDate = new Date(new Date().getFullYear() - 100, 0, 1);
-  const futureDate = new Date(new Date().getFullYear() + 100, 0, 1);
   const sortByStartDate = sortedBy.indexOf('start_date') > -1;
   const sortOrderAsc = sortedBy.indexOf('asc') > -1;
 
   epics.sort((a, b) => {
-    let aDate;
-    let bDate;
-
-    if (sortByStartDate) {
-      [aDate, bDate] = assignDates(a, b, {
-        dateUndefined: 'startDateUndefined',
-        outOfRange: 'startDateOutOfRange',
-        originalDate: 'originalStartDate',
-        date: 'startDate',
-        proxyDate: pastDate,
-      });
-    } else {
-      [aDate, bDate] = assignDates(a, b, {
-        dateUndefined: 'endDateUndefined',
-        outOfRange: 'endDateOutOfRange',
-        originalDate: 'originalEndDate',
-        date: 'endDate',
-        proxyDate: futureDate,
-      });
-    }
+    const [aDate, bDate] = assignDates(a, b, {
+      dateUndefined: sortByStartDate ? 'startDateUndefined' : 'endDateUndefined',
+      outOfRange: sortByStartDate ? 'startDateOutOfRange' : 'endDateOutOfRange',
+      originalDate: sortByStartDate ? 'originalStartDate' : 'originalEndDate',
+      date: sortByStartDate ? 'startDate' : 'endDate',
+      proxyDate: sortByStartDate ? PAST_DATE : FUTURE_DATE,
+    });
 
     // Sort in ascending or descending order
     if (aDate.getTime() < bDate.getTime()) {