Mostly fixed Collector #1129. Badly formed ISO8601 dates are rejected,

except that 'Z' is still allowed in front of a '+/-HH:MM' timezone.  I
left that in since it was used elsewhere in the code, and was probably
harmless, whereas the other parse problems caused dates like "2003-2-5"
to be accepted as valid and silently converted into "2003-01-01".

Also re-exposed the DateTime-specific exceptions as attributes of the
DateTime class.  During their recent converted from strings to classes,
they were removed.

doc/CHANGES.txt

@@ -34,6 +34,8 @@ Zope Changes
 
     Bugs fixed
 
+     - Collector #1129: Improper parsing of ISO8601 in DateTime.
+
      - Removed pervasive use of string exceptions (some may still be
        hiding in the woodwork, but all raise's with string literals are
        gone).

lib/python/DateTime/DateTime.py

@@ -12,7 +12,7 @@
 ##############################################################################
 """Encapsulation of date/time values"""
 
-__version__='$Revision: 1.91 $'[11:-2]
+__version__='$Revision: 1.92 $'[11:-2]
 
 
 import os, re, math,  DateTimeZone
@@ -497,6 +497,12 @@ class DateTime:
             then the current date/time is returned, represented in the
             timezone of the local machine. 
 
+    # Make class-specific exceptions available as attributes.
+    DateError = DateError
+    TimeError = TimeError
+    DateTimeError = DateTimeError
+    SyntaxError = SyntaxError
+
           - If the function is invoked with a single string argument
             which is a recognized timezone name, an object representing
             the current time is returned, represented in the specified
@@ -1657,7 +1663,8 @@ class DateTime:
         hour=minute=seconds=hour_off=min_off=0
 
         datereg = re.compile('([0-9]{4})(-([0-9][0-9]))?(-([0-9][0-9]))?')
-        timereg = re.compile('([0-9]{2})(:([0-9][0-9]))?(:([0-9][0-9]))?(\.[0-9]{1,20})?')
+        timereg = re.compile('T([0-9]{2})(:([0-9][0-9]))?(:([0-9][0-9]))?(\.[0-9]{1,20})?')
+        zonereg = re.compile('([+-][0-9][0-9])(:([0-9][0-9]))')
 
         # Date part
 
@@ -1666,21 +1673,33 @@ class DateTime:
         if fields[1]:   year  = int(fields[1])
         if fields[3]:   month = int(fields[3])
         if fields[5]:   day   = int(fields[5])
+        t = fields[6]
+        if t:
+            if not fields[5]:
+                # Specifying time requires specifying a day.
+                raise IndexError
 
-        if s.find('T')>-1:
-            fields = timereg.split(s[s.find('T')+1:])
+            fields = timereg.split(t)
 
             if fields[1]:   hour     = int(fields[1])
             if fields[3]:   minute   = int(fields[3])
             if fields[5]:   seconds  = int(fields[5])
             if fields[6]:   seconds  = seconds+float(fields[6])
-
-        if s.find('Z')>-1:
-            pass
-
-        if s[-3]==':' and s[-6] in ['+','-']:
-            hour_off = int(s[-6:-3])
-            min_off  = int(s[-2:])
+            z = fields[7]
+            
+	    if z and z.startswith('Z'):
+                # Waaaa! This is wrong, since 'Z' and '+HH:MM'
+                # are supposed to be mutually exclusive.
+                # It's only here to prevent breaking 2.7 beta.
+                z = z[1:]
+
+            if z:
+                fields = zonereg.split(z)
+                hour_off = int(fields[1])
+                min_off  = int(fields[3])
+                if fields[4]:
+                    # Garbage after time zone
+                    raise IndexError
 
         return year,month,day,hour,minute,seconds,'GMT%+03d%02d' % (hour_off,min_off)
 

lib/python/DateTime/tests/testDateTime.py

@@ -257,9 +257,17 @@ class DateTimeTests(unittest.TestCase):
         isoDt = DateTime('2002-05-02T08:00:00Z')
         self.assertEqual( ref0, isoDt)
 
-        isoDt = DateTime('2002-05-02T08:00:00Z-04:00')
+        isoDt = DateTime('2002-05-02T08:00:00-04:00')
         self.assertEqual( ref1, isoDt)
 
+        dgood = '2002-05-02'
+        tgood = 'T08:00:00-04:00'
+        for dbad in '2002-5-2', '2002-10-2', '2002-2-10', '02-2-10':
+            self.assertRaises(DateTime.SyntaxError, DateTime, dbad)
+            self.assertRaises(DateTime.SyntaxError, DateTime, dbad + tgood)
+        for tbad in '08:00', 'T8:00': #, 'T08:00Z-04:00':
+            self.assertRaises(DateTime.SyntaxError, DateTime, dgood + tbad)
+
     def testJulianWeek(self):
         """ check JulianDayWeek function """
 
@@ -279,13 +287,13 @@ class DateTimeTests(unittest.TestCase):
 
     def testRFC822(self):
         '''rfc822 conversion'''
-        dt = DateTime('2002-05-02T08:00:00Z+00:00')
+        dt = DateTime('2002-05-02T08:00:00+00:00')
         self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 +0000')
 
-        dt = DateTime('2002-05-02T08:00:00Z+02:00')
+        dt = DateTime('2002-05-02T08:00:00+02:00')
         self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 +0200')
 
-        dt = DateTime('2002-05-02T08:00:00Z-02:00')
+        dt = DateTime('2002-05-02T08:00:00-02:00')
         self.assertEqual(dt.rfc822(), 'Thu, 02 May 2002 08:00:00 -0200')
 
         # Checking that conversion from local time is working.