From b73ffae7529b75e40391f8b163c5230040faeaf2 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 14 Sep 2016 09:16:06 -0700
Subject: [PATCH] Make SiteStatsUpdate implement MergeableUpdate

Change-Id: I53c9bf133f0707f2fa203ddd1a7fcb65be8b1329
---
 includes/deferred/SiteStatsUpdate.php | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/includes/deferred/SiteStatsUpdate.php b/includes/deferred/SiteStatsUpdate.php
index d8bc35b2f5..ab4a609d01 100644
--- a/includes/deferred/SiteStatsUpdate.php
+++ b/includes/deferred/SiteStatsUpdate.php
@@ -17,26 +17,25 @@
  *
  * @file
  */
+use Wikimedia\Assert\Assert;
 
 /**
  * Class for handling updates to the site_stats table
  */
-class SiteStatsUpdate implements DeferrableUpdate {
+class SiteStatsUpdate implements DeferrableUpdate, MergeableUpdate {
 	/** @var int */
 	protected $edits = 0;
-
 	/** @var int */
 	protected $pages = 0;
-
 	/** @var int */
 	protected $articles = 0;
-
 	/** @var int */
 	protected $users = 0;
-
 	/** @var int */
 	protected $images = 0;
 
+	private static $counters = [ 'edits', 'pages', 'articles', 'users', 'images' ];
+
 	// @todo deprecate this constructor
 	function __construct( $views, $edits, $good, $pages = 0, $users = 0 ) {
 		$this->edits = $edits;
@@ -45,6 +44,15 @@ class SiteStatsUpdate implements DeferrableUpdate {
 		$this->users = $users;
 	}
 
+	public function merge( MergeableUpdate $update ) {
+		/** @var SiteStatsUpdate $update */
+		Assert::parameterType( __CLASS__, $update, '$update' );
+
+		foreach ( self::$counters as $field ) {
+			$this->$field += $update->$field;
+		}
+	}
+
 	/**
 	 * @param array $deltas
 	 * @return SiteStatsUpdate
@@ -52,8 +60,7 @@ class SiteStatsUpdate implements DeferrableUpdate {
 	public static function factory( array $deltas ) {
 		$update = new self( 0, 0, 0 );
 
-		$fields = [ 'views', 'edits', 'pages', 'articles', 'users', 'images' ];
-		foreach ( $fields as $field ) {
+		foreach ( self::$counters as $field ) {
 			if ( isset( $deltas[$field] ) && $deltas[$field] ) {
 				$update->$field = $deltas[$field];
 			}
-- 
2.20.1