From 4fa4c00318efddb1a68a99cb4b078eef0eadbd20 Mon Sep 17 00:00:00 2001
From: rfm <rfm@72102866-910b-0410-8b05-ffd578937521>
Date: Mon, 23 Oct 2006 12:24:52 +0000
Subject: [PATCH] Fix bug #18088

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@23950 72102866-910b-0410-8b05-ffd578937521
---
 ChangeLog                           |  5 +++++
 Headers/Foundation/NSCalendarDate.h |  2 +-
 Source/NSCalendarDate.m             | 16 ++++++++++------
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a32ad101b..4709b7b2b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2006-10-23  Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSCalendarDate: when adding offset to a date, work in
+	the timezone for the date rather than in GMT ... fixes bug #18088
+
 2006-10-20  Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Source/Additions/GSPrivate.m:
diff --git a/Headers/Foundation/NSCalendarDate.h b/Headers/Foundation/NSCalendarDate.h
index 0cee1c525..3632f85fb 100644
--- a/Headers/Foundation/NSCalendarDate.h
+++ b/Headers/Foundation/NSCalendarDate.h
@@ -68,7 +68,7 @@ extern "C" {
 	     second: (unsigned int)second
 	   timeZone: (NSTimeZone*)aTimeZone;
 
-// Retreiving Date Elements
+// Retrieving Date Elements
 - (int) dayOfCommonEra;
 - (int) dayOfMonth;
 - (int) dayOfWeek;
diff --git a/Source/NSCalendarDate.m b/Source/NSCalendarDate.m
index 1f6c1aee9..104df24e6 100644
--- a/Source/NSCalendarDate.m
+++ b/Source/NSCalendarDate.m
@@ -2378,13 +2378,15 @@ static void Grow(DescriptionInfo *info, unsigned size)
   NSTimeInterval	newOffset;
   int			i, year, month, day, hour, minute, second, mil;
 
-  oldOffset = offset(_time_zone, self);
-  /*
-   * Break into components in GMT time zone.
+  /* Apply timezone offset to _seconds_since_ref from GMT to local time,
+   * then break into components in local time zone.
    */
-  GSBreakTime(_seconds_since_ref, &year, &month, &day, &hour, &minute,
-    &second, &mil);
+  oldOffset = offset(_time_zone, self);
+  s = _seconds_since_ref + oldOffset;
+  GSBreakTime(s, &year, &month, &day, &hour, &minute, &second, &mil);
 
+  /* Apply required offsets to get new local time.
+   */
   while (years != 0 || months != 0 || days != 0
     || hours != 0 || minutes != 0 || seconds != 0)
     {
@@ -2473,9 +2475,11 @@ static void Grow(DescriptionInfo *info, unsigned size)
     }
 
   /*
-   * Reassemble in GMT time zone.
+   * Reassemble and apply original timezone offset to get
+   * _seconds_since_ref back to GMT.
    */
   s = GSTime(day, month, year, hour, minute, second, mil);
+  s -= oldOffset;
   c = [NSCalendarDate alloc];
   c->_calendar_format = cformat;
   c->_time_zone = RETAIN([self timeZone]);