Remade rfc822() to utilize the _tzoffset method. Much cleaner and better code.

Remade the test code for rfc822() to provide more stable tests.

lib/python/DateTime/DateTime.py

@@ -12,7 +12,7 @@
 ##############################################################################
 """Encapsulation of date/time values"""
 
-__version__='$Revision: 1.81 $'[11:-2]
+__version__='$Revision: 1.82 $'[11:-2]
 
 
 import re,sys, os, math,  DateTimeZone
@@ -362,6 +362,10 @@ def _calendarday(j):
     return int(yr),int(mo),int(dy)
 
 def _tzoffset(tz, t):
+    """Returns the offset in seconds to GMT from a specific timezone (tz) at 
+    a specific time (t).  NB! The _tzoffset result is the same same sign as 
+    the time zone, i.e. GMT+2 has a 7200 second offset. This is the opposite 
+    sign of time.timezone which (confusingly) is -7200 for GMT+2."""
     try:
         return DateTime._tzinfo[tz].info(t)[0]
     except:
@@ -400,7 +404,10 @@ def safelocaltime(t):
     return rval
 
 def _tzoffset2rfc822zone(seconds):
-    return "%+03d%02d" % divmod( (-seconds/60), 60) 
+    """Takes an offset, such as from _tzoffset(), and returns an rfc822 
+       compliant zone specification. Please note that the result of 
+       _tzoffset() is the negative of what time.localzone and time.altzone is."""
+    return "%+03d%02d" % divmod( (seconds/60), 60) 
 
 
 class DateTime:
@@ -1437,18 +1444,12 @@ class DateTime:
 
     def rfc822(self):
         """Return the date in RFC 822 format"""
-        if self._tz == self._localzone0: #Use local standard time
-            tzoffset = _tzoffset2rfc822zone(timezone)
-        elif self._tz == self._localzone1: # Use local daylight saving time
-            tzoffset = _tzoffset2rfc822zone(altzone)
-        else:
-            tzoffset = '-0000' # unknown time zone offset
+        tzoffset = _tzoffset2rfc822zone(_tzoffset(self._tz, self._t))
             
         return '%s, %2.2d %s %d %2.2d:%2.2d:%2.2d %s' % (
             self._aday,self._day,self._amon,self._year,
             self._hour,self._minute,self._nearsec,tzoffset)
 
-
     # New formats
     def fCommon(self):
         """Return a string representing the object\'s value

lib/python/DateTime/tests/testDateTime.py

@@ -249,22 +249,31 @@ class DateTimeTests(unittest.TestCase):
 
     def testRFC822(self):
         '''rfc822 conversion'''
-        isDST = time.localtime(time.time())[8]
-        if isDST:
-            offset = time.altzone
-        else:
-            offset = time.timezone
-
-        rfc822zone = "%+03d%02d" % divmod((-offset/60), 60)
-        wrongzone = "%+03d:%02d" % divmod((60-offset/60), 60) #one hour off, ISO format
-
-        # Create a local DateTime and test
-        dt = DateTime(2002, 5, 2, 8, 0, 0)
-        self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00' + ' ' + rfc822zone)
-
-        # Create a non-local date time and test
-        dt = DateTime('2002-05-02T08:00:00Z'+wrongzone)
-        self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 -0000')
+        dt = DateTime('2002-05-02T08:00:00Z+00:00')
+        self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 +0000')
+
+        dt = DateTime('2002-05-02T08:00:00Z+02:00')
+        self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 +0200')
+
+        dt = DateTime('2002-05-02T08:00:00Z-02:00')
+        self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 -0200')
+
+        # Checking that conversion from local time is working.
+        dt = DateTime()
+        dts = dt.rfc822().split(' ')
+        times = dts[4].split(':')
+        _isDST = time.localtime(time.time())[8]
+        if _isDST: offset = time.altzone
+        else:      offset = time.timezone
+
+        self.assertEqual(dts[0], dt.aDay() + ',')
+        self.assertEqual(int(dts[1]), dt.day())
+        self.assertEqual(dts[2], dt.aMonth())
+        self.assertEqual(int(dts[3]), dt.year())
+        self.assertEqual(int(times[0]), dt.h_24())
+        self.assertEqual(int(times[1]), dt.minute())
+        self.assertEqual(int(times[2]), int(dt.second()))
+        self.assertEqual(dts[5], "%+03d%02d" % divmod( (-offset/60), 60) )
 
 
 def test_suite():