From 437f60f3589cae2929bb9888bb6eb2dbdfa26a73 Mon Sep 17 00:00:00 2001
From: aude <aude.wiki@gmail.com>
Date: Mon, 15 Feb 2016 16:19:58 +0100
Subject: [PATCH] Add ContentHandler::supportsCategories method

and check for this in WikiPage::doEditUpdates before
inserting a new CategoryMembershipChangeJob.

Some content models like the Wikibase ones do not
have categories and it's wasteful to add these jobs
for all Wikibase edits.

Bug: T126977
Change-Id: I2c54a4ba1546445dc41101e15cb83a2c6cc2b1c9
---
 RELEASE-NOTES-1.27                                    |  3 +++
 includes/content/ContentHandler.php                   | 10 ++++++++++
 includes/page/WikiPage.php                            |  1 +
 tests/phpunit/includes/content/ContentHandlerTest.php |  5 +++++
 4 files changed, 19 insertions(+)

diff --git a/RELEASE-NOTES-1.27 b/RELEASE-NOTES-1.27
index 867abd7a12..b8ec76d657 100644
--- a/RELEASE-NOTES-1.27
+++ b/RELEASE-NOTES-1.27
@@ -319,6 +319,9 @@ changes to languages because of Phabricator reports.
   a user forgot password/account was stolen.
 * wfCheckEntropy() was removed (deprecated in 1.27).
 * Browser support for Internet Explorer 8 lowered from Grade A to Grade C.
+* ContentHandler::supportsCategories method added. Default is true.
+  CategoryMembershipChangeJob updates are skipped for content that
+  does not support categories.
 
 == Compatibility ==
 
diff --git a/includes/content/ContentHandler.php b/includes/content/ContentHandler.php
index 6bc6abfda7..9ab11f3b68 100644
--- a/includes/content/ContentHandler.php
+++ b/includes/content/ContentHandler.php
@@ -1082,6 +1082,16 @@ abstract class ContentHandler {
 		return false;
 	}
 
+	/**
+	 * Returns true if this content model supports categories.
+	 * The default implementation returns true.
+	 *
+	 * @return bool Always true.
+	 */
+	public function supportsCategories() {
+		return true;
+	}
+
 	/**
 	 * Returns true if this content model supports redirects.
 	 * This default implementation returns false.
diff --git a/includes/page/WikiPage.php b/includes/page/WikiPage.php
index 330889081d..27412edfcb 100644
--- a/includes/page/WikiPage.php
+++ b/includes/page/WikiPage.php
@@ -2261,6 +2261,7 @@ class WikiPage implements Page, IDBAccessObject {
 				DeferredUpdates::addUpdate( $update );
 			}
 			if ( $wgRCWatchCategoryMembership
+				&& $this->getContentHandler()->supportsCategories() === true
 				&& ( $options['changed'] || $options['created'] )
 				&& !$options['restored']
 			) {
diff --git a/tests/phpunit/includes/content/ContentHandlerTest.php b/tests/phpunit/includes/content/ContentHandlerTest.php
index 9c17c3ee81..91f27fbe71 100644
--- a/tests/phpunit/includes/content/ContentHandlerTest.php
+++ b/tests/phpunit/includes/content/ContentHandlerTest.php
@@ -350,6 +350,11 @@ class ContentHandlerTest extends MediaWikiTestCase {
 	}
 	*/
 
+	public function testSupportsCategories() {
+		$handler = new DummyContentHandlerForTesting( CONTENT_MODEL_WIKITEXT );
+		$this->assertTrue( $handler->supportsCategories(), 'content model supports categories' );
+	}
+
 	public function testSupportsDirectEditing() {
 		$handler = new DummyContentHandlerForTesting( CONTENT_MODEL_JSON );
 		$this->assertFalse( $handler->supportsDirectEditing(), 'direct editing is not supported' );
-- 
2.20.1