(bug 46787) API: Fix rccontinue handling

There are several bugs in Icc43b62f:
* When handing the continuation, the code checks for dir=descending when
  the actual value is dir=older.
* When the above is fixed, the continuation code assumes "ORDER BY
  rc_timestamp DESC, rc_id ASC", which would filesort.
* rc_id is not added to the ORDER BY clause anyway.

Bug: 46787
Change-Id: Ia6ebd4ea0458b8013d4ecb71954dcfbdacff2c00

diff --git a/includes/api/ApiQueryRecentChanges.php b/includes/api/ApiQueryRecentChanges.php
index 72e80b8..8aceab2 100644 (file)
--- a/includes/api/ApiQueryRecentChanges.php
+++ b/includes/api/ApiQueryRecentChanges.php
@@ -159,15 +159,20 @@ class ApiQueryRecentChanges extends ApiQueryGeneratorBase {
 
                        $timestamp = $this->getDB()->addQuotes( wfTimestamp( TS_MW, $cont[0] ) );
                        $id = intval( $cont[1] );
-                       $op = $params['dir'] == 'descending' ? '<' : '>';
+                       $op = $params['dir'] === 'older' ? '<' : '>';
 
                        $this->addWhere(
                                "rc_timestamp $op $timestamp OR " .
                                "(rc_timestamp = $timestamp AND " .
-                               "rc_id <= $id)"
+                               "rc_id $op= $id)"
                        );
                }
 
+               $order = $params['dir'] === 'older' ? 'DESC' : 'ASC';
+               $this->addOption( 'ORDER BY', array(
+                       "rc_timestamp $order",
+                       "rc_id $order",
+               ) );
 
                $this->addWhereFld( 'rc_namespace', $params['namespace'] );
                $this->addWhereFld( 'rc_deleted', 0 );