MediaWikiServices: Don't assume, that old and new instances contains the same services

[lhc/web/wiklou.git] / includes / MediaWikiServices.php

diff --git a/includes/MediaWikiServices.php b/includes/MediaWikiServices.php
index 49891df..037e96f 100644 (file)
--- a/includes/MediaWikiServices.php
+++ b/includes/MediaWikiServices.php
@@ -198,7 +198,14 @@ class MediaWikiServices extends ServiceContainer {
         */
        private function salvage( self $other ) {
                foreach ( $this->getServiceNames() as $name ) {
-                       $oldService = $other->peekService( $name );
+                       // The service could be new in the new instance and not registered in the
+                       // other instance (e.g. an extension that was loaded after the instantiation of
+                       // the other instance. Skip this service in this case. See T143974
+                       try {
+                               $oldService = $other->peekService( $name );
+                       } catch ( NoSuchServiceException $e ) {
+                               continue;
+                       }
 
                        if ( $oldService instanceof SalvageableService ) {
                                /** @var SalvageableService $newService */