Handle revisions with different content models in EditPage

Disable editing and serialize using the default format if the revision
has a different content model from the current one.

Bug: T73163
Change-Id: If28de7a3612d414a4366e3d493598244c0754b90

diff --git a/includes/EditPage.php b/includes/EditPage.php
index 8571cd7..81f35f9 100644 (file)
--- a/includes/EditPage.php
+++ b/includes/EditPage.php
@@ -537,6 +537,20 @@ class EditPage {
                        return;
                }
 
+               $revision = $this->mArticle->getRevisionFetched();
+               // Disallow editing revisions with content models different from the current one
+               if ( $revision && $revision->getContentModel() !== $this->contentModel ) {
+                       $this->displayViewSourcePage(
+                               $this->getContentObject(),
+                               wfMessage(
+                                       'contentmodelediterror',
+                                       $revision->getContentModel(),
+                                       $this->contentModel
+                               )->plain()
+                       );
+                       return;
+               }
+
                $this->isConflict = false;
                // css / js subpages of user pages get a special treatment
                $this->isCssJsSubpage = $this->mTitle->isCssJsSubpage();
@@ -647,6 +661,20 @@ class EditPage {
                        throw new PermissionsError( $action, $permErrors );
                }
 
+               $this->displayViewSourcePage(
+                       $content,
+                       $wgOut->formatPermissionsErrorMessage( $permErrors, 'edit' )
+               );
+       }
+
+       /**
+        * Display a read-only View Source page
+        * @param Content $content content object
+        * @param string $errorMessage additional wikitext error message to display
+        */
+       protected function displayViewSourcePage( Content $content, $errorMessage = '' ) {
+               global $wgOut;
+
                Hooks::run( 'EditPage::showReadOnlyForm:initial', array( $this, &$wgOut ) );
 
                $wgOut->setRobotPolicy( 'noindex,nofollow' );
@@ -658,8 +686,10 @@ class EditPage {
                $wgOut->addHTML( $this->editFormPageTop );
                $wgOut->addHTML( $this->editFormTextTop );
 
-               $wgOut->addWikiText( $wgOut->formatPermissionsErrorMessage( $permErrors, 'edit' ) );
-               $wgOut->addHTML( "<hr />\n" );
+               if ( $errorMessage !== '' ) {
+                       $wgOut->addWikiText( $errorMessage );
+                       $wgOut->addHTML( "<hr />\n" );
+               }
 
                # If the user made changes, preserve them when showing the markup
                # (This happens when a user is blocked during edit, for instance)
@@ -667,7 +697,13 @@ class EditPage {
                        $text = $this->textbox1;
                        $wgOut->addWikiMsg( 'viewyourtext' );
                } else {
-                       $text = $this->toEditText( $content );
+                       try {
+                               $text = $this->toEditText( $content );
+                       } catch ( MWException $e ) {
+                               # Serialize using the default format if the content model is not supported
+                               # (e.g. for an old revision with a different model)
+                               $text = $content->serialize();
+                       }
                        $wgOut->addWikiMsg( 'viewsourcetext' );
                }
 

diff --git a/languages/i18n/en.json b/languages/i18n/en.json
index 8f4ef96..e2440fe 100644 (file)
--- a/languages/i18n/en.json
+++ b/languages/i18n/en.json
@@ -692,6 +692,7 @@
        "permissionserrors": "Permission error",
        "permissionserrorstext": "You do not have permission to do that, for the following {{PLURAL:$1|reason|reasons}}:",
        "permissionserrorstext-withaction": "You do not have permission to $2, for the following {{PLURAL:$1|reason|reasons}}:",
+       "contentmodelediterror": "You cannot edit this revision because its content model is <code>$1</code>, but the current content model of the page is <code>$2</code>.",
        "recreate-moveddeleted-warn": "<strong>Warning: You are recreating a page that was previously deleted.</strong>\n\nYou should consider whether it is appropriate to continue editing this page.\nThe deletion and move log for this page are provided here for convenience:",
        "moveddeleted-notice": "This page has been deleted.\nThe deletion and move log for the page are provided below for reference.",
        "moveddeleted-notice-recent": "Sorry, this page was recently deleted (within the last 24 hours).\nThe deletion and move log for the page are provided below for reference.",

diff --git a/languages/i18n/qqq.json b/languages/i18n/qqq.json
index 95bd205..6a11080 100644 (file)
--- a/languages/i18n/qqq.json
+++ b/languages/i18n/qqq.json
@@ -865,6 +865,7 @@
        "permissionserrors": "Used as title of error message.\n\nSee also:\n* {{msg-mw|loginreqtitle}}\n{{Identical|Permission error}}",
        "permissionserrorstext": "This message is \"without action\" version of {{msg-mw|Permissionserrorstext-withaction}}.\n\nParameters:\n* $1 - the number of reasons that were found why ''the action'' cannot be performed",
        "permissionserrorstext-withaction": "This message is \"with action\" version of {{msg-mw|Permissionserrorstext}}.\n\nParameters:\n* $1 - the number of reasons that were found why the action cannot be performed\n* $2 - one of the action-* messages (for example {{msg-mw|action-edit}}) or other such messages tagged with {{tl|doc-action}} in their documentation\n\nPlease report at [[Support]] if you are unable to properly translate this message. Also see [[phab:T16246]] (now closed) for background.",
+       "contentmodelediterror": "Error message shown when trying to edit an old revision with a content model different from that of the current revision\n* $1 - content model of the old revision\n* $2 - content model of the current revision",
        "recreate-moveddeleted-warn": "Warning shown when creating a page which has already been deleted. See for example [[Test]].",
        "moveddeleted-notice": "Shown on top of a deleted page in normal view modus ([{{canonicalurl:Test}} example]).",
        "moveddeleted-notice-recent": "Shown on top of a recently deleted page in normal view modus ([{{canonicalurl:Test}} example]).",