Create DifferenceEngine before calling GetDifferenceEngine

[lhc/web/wiklou.git] / includes / content / ContentHandler.php

diff --git a/includes/content/ContentHandler.php b/includes/content/ContentHandler.php
index 004e38a..0a451b2 100644 (file)
--- a/includes/content/ContentHandler.php
+++ b/includes/content/ContentHandler.php
@@ -614,6 +614,14 @@ abstract class ContentHandler {
        /**
         * Factory for creating an appropriate DifferenceEngine for this content model.
         *
+        * The DifferenceEngine subclass to use is selected in getDiffEngineClass(). The
+        * GetDifferenceEngine hook will receive the DifferenceEngine object and can replace or
+        * wrap it.
+        * (Note that in older versions of MediaWiki the hook documentation instructed extensions
+        * to return false from the hook; you should not rely on always being able to decorate
+        * the DifferenceEngine instance from the hook. If the owner of the content type wants to
+        * decorare the instance, overriding this method is a safer approach.)
+        *
         * @since 1.21
         *
         * @param IContextSource $context Context to use, anything else will be ignored.
@@ -629,15 +637,11 @@ abstract class ContentHandler {
                $rcid = 0, // FIXME: Deprecated, no longer used
                $refreshCache = false, $unhide = false
        ) {
-               // hook: get difference engine
-               $differenceEngine = null;
-               if ( !Hooks::run( 'GetDifferenceEngine',
-                       [ $context, $old, $new, $refreshCache, $unhide, &$differenceEngine ]
-               ) ) {
-                       return $differenceEngine;
-               }
                $diffEngineClass = $this->getDiffEngineClass();
-               return new $diffEngineClass( $context, $old, $new, $rcid, $refreshCache, $unhide );
+               $differenceEngine = new $diffEngineClass( $context, $old, $new, $rcid, $refreshCache, $unhide );
+               Hooks::run( 'GetDifferenceEngine', [ $context, $old, $new, $refreshCache, $unhide,
+                       &$differenceEngine ] );
+               return $differenceEngine;
        }
 
        /**