Merge "RevisionStore: Avoid exception on prev/next of deleted revision"

[lhc/web/wiklou.git] / includes / Revision / RevisionStore.php

diff --git a/includes/Revision/RevisionStore.php b/includes/Revision/RevisionStore.php
index ab73b2c..cf19ffb 100644 (file)
--- a/includes/Revision/RevisionStore.php
+++ b/includes/Revision/RevisionStore.php
@@ -2523,45 +2523,78 @@ class RevisionStore
        }
 
        /**
-        * Get previous revision for this title
+        * Get the revision before $rev in the page's history, if any.
+        * Will return null for the first revision but also for deleted or unsaved revisions.
         *
         * MCR migration note: this replaces Revision::getPrevious
         *
+        * @see Title::getPreviousRevisionID
+        * @see PageArchive::getPreviousRevision
+        *
         * @param RevisionRecord $rev
         * @param Title|null $title if known (optional)
         *
         * @return RevisionRecord|null
         */
        public function getPreviousRevision( RevisionRecord $rev, Title $title = null ) {
+               if ( !$rev->getId() || !$rev->getPageId() ) {
+                       // revision is unsaved or otherwise incomplete
+                       return null;
+               }
+
+               if ( $rev instanceof RevisionArchiveRecord ) {
+                       // revision is deleted, so it's not part of the page history
+                       return null;
+               }
+
                if ( $title === null ) {
+                       // this would fail for deleted revisions
                        $title = $this->getTitle( $rev->getPageId(), $rev->getId() );
                }
+
                $prev = $title->getPreviousRevisionID( $rev->getId() );
-               if ( $prev ) {
-                       return $this->getRevisionByTitle( $title, $prev );
+               if ( !$prev ) {
+                       return null;
                }
-               return null;
+
+               return $this->getRevisionByTitle( $title, $prev );
        }
 
        /**
-        * Get next revision for this title
+        * Get the revision after $rev in the page's history, if any.
+        * Will return null for the latest revision but also for deleted or unsaved revisions.
         *
         * MCR migration note: this replaces Revision::getNext
         *
+        * @see Title::getNextRevisionID
+        *
         * @param RevisionRecord $rev
         * @param Title|null $title if known (optional)
         *
         * @return RevisionRecord|null
         */
        public function getNextRevision( RevisionRecord $rev, Title $title = null ) {
+               if ( !$rev->getId() || !$rev->getPageId() ) {
+                       // revision is unsaved or otherwise incomplete
+                       return null;
+               }
+
+               if ( $rev instanceof RevisionArchiveRecord ) {
+                       // revision is deleted, so it's not part of the page history
+                       return null;
+               }
+
                if ( $title === null ) {
+                       // this would fail for deleted revisions
                        $title = $this->getTitle( $rev->getPageId(), $rev->getId() );
                }
+
                $next = $title->getNextRevisionID( $rev->getId() );
-               if ( $next ) {
-                       return $this->getRevisionByTitle( $title, $next );
+               if ( !$next ) {
+                       return null;
                }
-               return null;
+
+               return $this->getRevisionByTitle( $title, $next );
        }
 
        /**