Added support for time zones. Thanks Luke Plant for the review. Fixed #2626.

For more information on this project, see this thread:
http://groups.google.com/group/django-developers/browse_thread/thread/cf0423bbb85b1bbf



git-svn-id: http://code.djangoproject.com/svn/django/trunk@17106 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/forms/fields.py

@@ -17,7 +17,7 @@ except ImportError:
 
 from django.core import validators
 from django.core.exceptions import ValidationError
-from django.forms.util import ErrorList
+from django.forms.util import ErrorList, from_current_timezone, to_current_timezone
 from django.forms.widgets import (TextInput, PasswordInput, HiddenInput,
     MultipleHiddenInput, ClearableFileInput, CheckboxInput, Select,
     NullBooleanSelect, SelectMultiple, DateInput, DateTimeInput, TimeInput,
@@ -409,6 +409,11 @@ class DateTimeField(BaseTemporalField):
         'invalid': _(u'Enter a valid date/time.'),
     }
 
+    def prepare_value(self, value):
+        if isinstance(value, datetime.datetime):
+            value = to_current_timezone(value)
+        return value
+
     def to_python(self, value):
         """
         Validates that the input can be converted to a datetime. Returns a
@@ -417,9 +422,10 @@ class DateTimeField(BaseTemporalField):
         if value in validators.EMPTY_VALUES:
             return None
         if isinstance(value, datetime.datetime):
-            return value
+            return from_current_timezone(value)
         if isinstance(value, datetime.date):
-            return datetime.datetime(value.year, value.month, value.day)
+            result = datetime.datetime(value.year, value.month, value.day)
+            return from_current_timezone(result)
         if isinstance(value, list):
             # Input comes from a SplitDateTimeWidget, for example. So, it's two
             # components: date and time.
@@ -428,7 +434,8 @@ class DateTimeField(BaseTemporalField):
             if value[0] in validators.EMPTY_VALUES and value[1] in validators.EMPTY_VALUES:
                 return None
             value = '%s %s' % tuple(value)
-        return super(DateTimeField, self).to_python(value)
+        result = super(DateTimeField, self).to_python(value)
+        return from_current_timezone(result)
 
     def strptime(self, value, format):
         return datetime.datetime.strptime(value, format)
@@ -979,7 +986,8 @@ class SplitDateTimeField(MultiValueField):
                 raise ValidationError(self.error_messages['invalid_date'])
             if data_list[1] in validators.EMPTY_VALUES:
                 raise ValidationError(self.error_messages['invalid_time'])
-            return datetime.datetime.combine(*data_list)
+            result = datetime.datetime.combine(*data_list)
+            return from_current_timezone(result)
         return None
 
 

django/forms/util.py

@@ -1,6 +1,9 @@
+from django.conf import settings
 from django.utils.html import conditional_escape
 from django.utils.encoding import StrAndUnicode, force_unicode
 from django.utils.safestring import mark_safe
+from django.utils import timezone
+from django.utils.translation import ugettext_lazy as _
 
 # Import ValidationError so that it can be imported from this
 # module to maintain backwards compatibility.
@@ -52,3 +55,31 @@ class ErrorList(list, StrAndUnicode):
     def __repr__(self):
         return repr([force_unicode(e) for e in self])
 
+# Utilities for time zone support in DateTimeField et al.
+
+def from_current_timezone(value):
+    """
+    When time zone support is enabled, convert naive datetimes
+    entered in the current time zone to aware datetimes.
+    """
+    if settings.USE_TZ and value is not None and timezone.is_naive(value):
+        current_timezone = timezone.get_current_timezone()
+        try:
+            return timezone.make_aware(value, current_timezone)
+        except Exception, e:
+            raise ValidationError(_('%(datetime)s couldn\'t be interpreted '
+                                    'in time zone %(current_timezone)s; it '
+                                    'may be ambiguous or it may not exist.')
+                                  % {'datetime': value,
+                                     'current_timezone': current_timezone})
+    return value
+
+def to_current_timezone(value):
+    """
+    When time zone support is enabled, convert aware datetimes
+    to naive dateimes in the current time zone for display.
+    """
+    if settings.USE_TZ and value is not None and timezone.is_aware(value):
+        current_timezone = timezone.get_current_timezone()
+        return timezone.make_naive(value, current_timezone)
+    return value

django/forms/widgets.py

@@ -10,7 +10,7 @@ from itertools import chain
 from urlparse import urljoin
 
 from django.conf import settings
-from django.forms.util import flatatt
+from django.forms.util import flatatt, to_current_timezone
 from django.utils.datastructures import MultiValueDict, MergeDict
 from django.utils.html import escape, conditional_escape
 from django.utils.translation import ugettext, ugettext_lazy
@@ -847,6 +847,7 @@ class SplitDateTimeWidget(MultiWidget):
 
     def decompress(self, value):
         if value:
+            value = to_current_timezone(value)
             return [value.date(), value.time().replace(microsecond=0)]
         return [None, None]