Fixed the usage of $flags in loadLastEdit()

Bug: T93976
Change-Id: I57eb41b463116ea27c0fc8dac8fff07db593499a

diff --git a/includes/page/WikiPage.php b/includes/page/WikiPage.php
index 5527ace..2315dc7 100644 (file)
--- a/includes/page/WikiPage.php
+++ b/includes/page/WikiPage.php
@@ -602,13 +602,23 @@ class WikiPage implements Page, IDBAccessObject {
                        return; // page doesn't exist or is missing page_latest info
                }
 
-               // Bug 37225: if session S1 loads the page row FOR UPDATE, the result always includes the
-               // latest changes committed. This is true even within REPEATABLE-READ transactions, where
-               // S1 normally only sees changes committed before the first S1 SELECT. Thus we need S1 to
-               // also gets the revision row FOR UPDATE; otherwise, it may not find it since a page row
-               // UPDATE and revision row INSERT by S2 may have happened after the first S1 SELECT.
-               // http://dev.mysql.com/doc/refman/5.0/en/set-transaction.html#isolevel_repeatable-read.
-               $flags = ( $this->mDataLoadedFrom == self::READ_LOCKING ) ? Revision::READ_LOCKING : 0;
+               if ( $this->mDataLoadedFrom == self::READ_LOCKING ) {
+                       // Bug 37225: if session S1 loads the page row FOR UPDATE, the result always
+                       // includes the latest changes committed. This is true even within REPEATABLE-READ
+                       // transactions, where S1 normally only sees changes committed before the first S1
+                       // SELECT. Thus we need S1 to also gets the revision row FOR UPDATE; otherwise, it
+                       // may not find it since a page row UPDATE and revision row INSERT by S2 may have
+                       // happened after the first S1 SELECT.
+                       // http://dev.mysql.com/doc/refman/5.0/en/set-transaction.html#isolevel_repeatable-read.
+                       $flags = Revision::READ_LOCKING;
+               } elseif ( $this->mDataLoadedFrom == self::READ_LATEST ) {
+                       // Bug T93976: if page_latest was loaded from the master, fetch the
+                       // revision from there as well, as it may not exist yet on a slave DB.
+                       // Also, this keeps the queries in the same REPEATABLE-READ snapshot.
+                       $flags = Revision::READ_LATEST;
+               } else {
+                       $flags = 0;
+               }
                $revision = Revision::newFromPageId( $this->getId(), $latest, $flags );
                if ( $revision ) { // sanity
                        $this->setLastEdit( $revision );