ZP-832 Run SyncCollections->CheckForChanges() stat comparing only on

first run, improved comment.

Released under the Affero GNU General Public License (AGPL) version 3.

src/lib/core/synccollections.php

@@ -483,8 +483,8 @@ class SyncCollections implements Iterator {
                         throw new StatusException(sprintf("Error initializing ChangesSink for folder id '%s'", $folderid), self::ERROR_WRONG_HIERARCHY);
                 }
 
-                // check if the folder stat changed since the last sync, if so generate a change for it
-                if (ZPush::GetBackend()->HasFolderStats() && $spa->HasFolderStat() && ZPush::GetBackend()->GetFolderStat($store, $spa->GetFolderId()) !== $spa->GetFolderStat()) {
+                // check if the folder stat changed since the last sync, if so generate a change for it (only on first run)
+                if ($this->waitingTime == 0 && ZPush::GetBackend()->HasFolderStats() && $spa->HasFolderStat() && ZPush::GetBackend()->GetFolderStat($store, $spa->GetFolderId()) !== $spa->GetFolderStat()) {
                     $this->changes[$spa->GetFolderId()] = 1;
                 }
             }

src/lib/default/backend.php

@@ -260,7 +260,8 @@ abstract class Backend implements IBackend {
      * @return string
      */
     public function GetFolderStat($store, $folderid) {
-        // as this is not implemented, the value returned will be different each time, resulting in a standard exporter setup.
+        // As this is not implemented, the value returned will change every hour.
+        // This will only be called if HasFolderStats() returns true.
         return "not implemented-".gmdate("Y-m-d-H");
     }