Extend phases instead of replacing them when updating a challenge

Author: ThomasKranitsas

src/services/ChallengeService.js

@@ -1229,7 +1229,15 @@ async function update (currentUser, challengeId, data, userToken, isFull) {
   }
 
   if (data.phases || data.startDate) {
-    const newPhases = data.phases || challenge.phases
+    if (data.phases && data.phases.length > 0) {
+      for (let i = 0; i < challenge.phases.length; i += 1) {
+        const updatedPhaseInfo = _.find(data.phases, p => p.phaseId === challenge.phases[i].phaseId)
+        if (updatedPhaseInfo) {
+          _.extend(challenge.phases[i], updatedPhaseInfo)
+        }
+      }
+    }
+    const newPhases = challenge.phases
     const newStartDate = data.startDate || challenge.startDate
 
     await helper.validatePhases(newPhases)