From 70e300e270bd8334870914808c66db0b66fcb1f6 Mon Sep 17 00:00:00 2001
From: Liangent <liangent@gmail.com>
Date: Sat, 29 Dec 2012 22:07:21 +0800
Subject: [PATCH] Do correct average year length arithmetic.

We have ( 24 * 3 + 25 ) leap years in total every 400 years in the
Gregorian calendar.

Change-Id: I2ad9036473afa914ecf8ddcf99ce27e316178f76
---
 languages/Language.php                   |  8 ++++----
 tests/phpunit/languages/LanguageTest.php | 25 ++++++++++++------------
 2 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/languages/Language.php b/languages/Language.php
index 80baf06339..c050ad262d 100644
--- a/languages/Language.php
+++ b/languages/Language.php
@@ -160,10 +160,10 @@ class Language {
 	 * @var array
 	 */
 	static public $durationIntervals = array(
-		'millennia' => 31557600000,
-		'centuries' => 3155760000,
-		'decades' => 315576000,
-		'years' => 31557600, // 86400 * 365.25
+		'millennia' => 31556952000,
+		'centuries' => 3155695200,
+		'decades' => 315569520,
+		'years' => 31556952, // 86400 * ( 365 + ( 24 * 3 + 25 ) / 400 )
 		'weeks' => 604800,
 		'days' => 86400,
 		'hours' => 3600,
diff --git a/tests/phpunit/languages/LanguageTest.php b/tests/phpunit/languages/LanguageTest.php
index 94ccfd018e..f75f444702 100644
--- a/tests/phpunit/languages/LanguageTest.php
+++ b/tests/phpunit/languages/LanguageTest.php
@@ -847,35 +847,36 @@ class LanguageTest extends LanguageClassesTestCase {
 				'2 days',
 			),
 			array(
-				365.25 * 86400, // 365.25 * 86400 = 31557600
+				// ( 365 + ( 24 * 3 + 25 ) / 400 ) * 86400 = 31556952
+				( 365 + ( 24 * 3 + 25 ) / 400.0 ) * 86400,
 				'1 year',
 			),
 			array(
-				2 * 31557600,
+				2 * 31556952,
 				'2 years',
 			),
 			array(
-				10 * 31557600,
+				10 * 31556952,
 				'1 decade',
 			),
 			array(
-				20 * 31557600,
+				20 * 31556952,
 				'2 decades',
 			),
 			array(
-				100 * 31557600,
+				100 * 31556952,
 				'1 century',
 			),
 			array(
-				200 * 31557600,
+				200 * 31556952,
 				'2 centuries',
 			),
 			array(
-				1000 * 31557600,
+				1000 * 31556952,
 				'1 millennium',
 			),
 			array(
-				2000 * 31557600,
+				2000 * 31556952,
 				'2 millennia',
 			),
 			array(
@@ -887,11 +888,11 @@ class LanguageTest extends LanguageClassesTestCase {
 				'1 hour and 1 second'
 			),
 			array(
-				31557600 + 2 * 86400 + 9000,
+				31556952 + 2 * 86400 + 9000,
 				'1 year, 2 days, 2 hours and 30 minutes'
 			),
 			array(
-				42 * 1000 * 31557600 + 42,
+				42 * 1000 * 31556952 + 42,
 				'42 millennia and 42 seconds'
 			),
 			array(
@@ -910,7 +911,7 @@ class LanguageTest extends LanguageClassesTestCase {
 				array( 'seconds' ),
 			),
 			array(
-				31557600 + 2 * 86400 + 9000,
+				31556952 + 2 * 86400 + 9000,
 				'1 year, 2 days and 150 minutes',
 				array( 'years', 'days', 'minutes' ),
 			),
@@ -920,7 +921,7 @@ class LanguageTest extends LanguageClassesTestCase {
 				array( 'years', 'days' ),
 			),
 			array(
-				31557600 + 2 * 86400 + 9000,
+				31556952 + 2 * 86400 + 9000,
 				'1 year, 2 days and 150 minutes',
 				array( 'minutes', 'days', 'years' ),
 			),
-- 
2.20.1