Fixed bug #77243 (Weekdays are calculated incorrectly for negative years)

Author: derickr

NEWS

@@ -4,6 +4,8 @@ PHP                                                                        NEWS
 
 - Date:
   . Fixed bug #74671 (DST timezone abbreviation has incorrect offset). (Derick)
+  . Fixed bug #77243 (Weekdays are calculated incorrectly for negative years).
+    (Derick)
   . Fixed bug #78139 (timezone_open accepts invalid timezone string argument).
     (Derick)
 

ext/date/lib/dow.c

@@ -52,7 +52,7 @@ static timelib_sll timelib_day_of_week_ex(timelib_sll y, timelib_sll m, timelib_
 	/* Only valid for Gregorian calendar, commented out as we don't handle
 	 * Julian calendar. We just return the 'wrong' day of week to be
 	 * consistent. */
-	c1 = century_value(y / 100);
+	c1 = century_value((y / 100) - (y<0));
 	y1 = positive_mod(y, 100);
 	m1 = timelib_is_leap(y) ? m_table_leap[m] : m_table_common[m];
 	dow = positive_mod((c1 + y1 + m1 + (y1 / 4) + d), 7);

ext/date/tests/bug49585.phpt

@@ -12,6 +12,6 @@ var_dump($date->format('r'));
 var_dump($date->format('c'));
 ?>
 --EXPECT--
-string(32) "Fri, 01 Jan -1500 00:00:00 +0000"
-string(38) "Mon, 01 Jan -2147483648 00:00:00 +0000"
+string(32) "Sun, 01 Jan -1500 00:00:00 +0000"
+string(38) "Tue, 01 Jan -2147483648 00:00:00 +0000"
 string(32) "-2147483648-01-01T00:00:00+00:00"

ext/date/tests/bug75851.phpt

@@ -13,9 +13,9 @@ echo date(DATE_ATOM."\n".DATE_RFC2822."\nc\nr\no\ny\nY\nU\n\n", PHP_INT_MAX);
 ?>
 --EXPECT--
 -292277022657-01-27T08:29:52+00:00
-Fri, 27 Jan -292277022657 08:29:52 +0000
+Sun, 27 Jan -292277022657 08:29:52 +0000
 -292277022657-01-27T08:29:52+00:00
-Fri, 27 Jan -292277022657 08:29:52 +0000
+Sun, 27 Jan -292277022657 08:29:52 +0000
 -292277022657
 -57
 -292277022657

ext/date/tests/bug77243.phpt

@@ -0,0 +1,34 @@
+--TEST--
+Bug #77243 (Weekdays are calculated incorrectly for negative years)
+--FILE--
+<?php
+date_default_timezone_set('UTC');
+
+$time=-62167046400; // 0000-01-03 0-01-1
+
+for ($i = -10; $i < 10; $i++ )
+{
+	echo date('Y-m-d o-W-N', $time + ($i * 86400)), "\n";
+}
+?>
+--EXPECT--
+-0001-12-24 -1-51-5
+-0001-12-25 -1-51-6
+-0001-12-26 -1-51-7
+-0001-12-27 -1-52-1
+-0001-12-28 -1-52-2
+-0001-12-29 -1-52-3
+-0001-12-30 -1-52-4
+-0001-12-31 -1-52-5
+0000-01-01 -1-52-6
+0000-01-02 -1-52-7
+0000-01-03 0-01-1
+0000-01-04 0-01-2
+0000-01-05 0-01-3
+0000-01-06 0-01-4
+0000-01-07 0-01-5
+0000-01-08 0-01-6
+0000-01-09 0-01-7
+0000-01-10 0-02-1
+0000-01-11 0-02-2
+0000-01-12 0-02-3