From 4136f8269b52de0c9274575b118604f7ebbda5e4 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 15 May 2013 11:16:16 -0700
Subject: [PATCH] Fixed total breakage of HashRing in 9d1cd9a.

* This had PHP warnings but no errors, but was broken.
* Added some unit tests for this class.

Change-Id: I7c7ea2c30ca747aae7a3c3951fc33c69052de085
---
 includes/HashRing.php                   |  1 +
 tests/phpunit/includes/HashRingTest.php | 53 +++++++++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 tests/phpunit/includes/HashRingTest.php

diff --git a/includes/HashRing.php b/includes/HashRing.php
index 73a38af949..cd39ad8185 100644
--- a/includes/HashRing.php
+++ b/includes/HashRing.php
@@ -49,6 +49,7 @@ class HashRing {
 			return strcmp( $hashes[$a], $hashes[$b] );
 		} );
 		// Fit the map to weight-proportionate one with a space of size RING_SIZE
+		$sum = array_sum( $map );
 		$standardMap = array();
 		foreach ( $map as $location => $weight ) {
 			$standardMap[$location] = (int)floor( $weight / $sum * self::RING_SIZE );
diff --git a/tests/phpunit/includes/HashRingTest.php b/tests/phpunit/includes/HashRingTest.php
new file mode 100644
index 0000000000..2d47fdf21c
--- /dev/null
+++ b/tests/phpunit/includes/HashRingTest.php
@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * @group HashRing
+ */
+class HashRingTest extends MediaWikiTestCase {
+	function testHashRing() {
+		$ring = new HashRing( array( 's1' => 1, 's2' => 1, 's3' => 2, 's4' => 2, 's5' => 2, 's6' => 3 ) );
+
+		$locations = array();
+		for ( $i=0; $i<20; $i++ ) {
+			$locations[ "hello$i"] = $ring->getLocation( "hello$i" );
+		}
+		$expectedLocations = array(
+			"hello0" => "s5",
+			"hello1" => "s6",
+			"hello2" => "s2",
+			"hello3" => "s5",
+			"hello4" => "s6",
+			"hello5" => "s4",
+			"hello6" => "s5",
+			"hello7" => "s4",
+			"hello8" => "s5",
+			"hello9" => "s5",
+			"hello10" => "s3",
+			"hello11" => "s6",
+			"hello12" => "s1",
+			"hello13" => "s3",
+			"hello14" => "s3",
+			"hello15" => "s5",
+			"hello16" => "s4",
+			"hello17" => "s6",
+			"hello18" => "s6",
+			"hello19" => "s3"
+		);
+
+		$this->assertEquals( $expectedLocations, $locations, 'Items placed at proper locations' );
+
+		$locations = array();
+		for ( $i=0; $i<5; $i++ ) {
+			$locations[ "hello$i"] = $ring->getLocations( "hello$i", 2 );
+		}
+
+		$expectedLocations = array(
+			"hello0" => array( "s5", "s6" ),
+			"hello1" => array( "s6", "s4" ),
+			"hello2" => array( "s2", "s1" ),
+			"hello3" => array( "s5", "s6" ),
+			"hello4" => array( "s6", "s4" ),
+		);
+		$this->assertEquals( $expectedLocations, $locations, 'Items placed at proper locations' );
+	}
+}
-- 
2.20.1