[1.0.X] Fixed #9522 -- Modified handling of values in base serializer so that field subclasses can define their own value_to_string() method for serialization. Thanks to Alex Koshelev for the report and initial patch.

Merge of r10554 from trunk.


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.0.X@10555 bcc190cf-cafb-0310-a4f2-bffc1f526a37

3 files changed, 27 insertions, 9 deletions

diff --git a/django/core/serializers/python.py b/django/core/serializers/python.py
index 0eeb485797..b672e4efc3 100644
--- a/django/core/serializers/python.py
+++ b/django/core/serializers/python.py
@@ -7,15 +7,15 @@ other serializers.
 from django.conf import settings
 from django.core.serializers import base
 from django.db import models
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import smart_unicode, is_protected_type
 
 class Serializer(base.Serializer):
     """
     Serializes a QuerySet to basic Python objects.
     """
-    
+
     internal_use_only = True
-    
+
     def start_serialization(self):
         self._current = None
         self.objects = []
@@ -35,7 +35,14 @@ class Serializer(base.Serializer):
         self._current = None
 
     def handle_field(self, obj, field):
-        self._current[field.name] = smart_unicode(getattr(obj, field.name), strings_only=True)
+        value = field._get_val_from_obj(obj)
+        # Protected types (i.e., primitives like None, numbers, dates,
+        # and Decimals) are passed through as is. All other values are
+        # converted to string first.
+        if is_protected_type(value):
+            self._current[field.name] = value
+        else:
+            self._current[field.name] = field.value_to_string(obj)
 
     def handle_fk_field(self, obj, field):
         related = getattr(obj, field.name)
diff --git a/django/core/serializers/xml_serializer.py b/django/core/serializers/xml_serializer.py
index 04498db00c..2d74fe28f3 100644
--- a/django/core/serializers/xml_serializer.py
+++ b/django/core/serializers/xml_serializer.py
@@ -65,11 +65,9 @@ class Serializer(base.Serializer):
             "type" : field.get_internal_type()
         })
 
-        # Get a "string version" of the object's data (this is handled by the
-        # serializer base class).
+        # Get a "string version" of the object's data.
         if getattr(obj, field.name) is not None:
-            value = self.get_string_value(obj, field)
-            self.xml.characters(smart_unicode(value))
+            self.xml.characters(field.value_to_string(obj))
         else:
             self.xml.addQuickElement("None")
 
diff --git a/django/utils/encoding.py b/django/utils/encoding.py
index 7e87b05c79..9388d67f4c 100644
--- a/django/utils/encoding.py
+++ b/django/utils/encoding.py
@@ -41,6 +41,19 @@ def smart_unicode(s, encoding='utf-8', strings_only=False, errors='strict'):
         return s
     return force_unicode(s, encoding, strings_only, errors)
 
+def is_protected_type(obj):
+    """Determine if the object instance is of a protected type.
+
+    Objects of protected types are preserved as-is when passed to
+    force_unicode(strings_only=True).
+    """
+    return isinstance(obj, (
+        types.NoneType,
+        int, long,
+        datetime.datetime, datetime.date, datetime.time,
+        float, Decimal)
+    )
+
 def force_unicode(s, encoding='utf-8', strings_only=False, errors='strict'):
     """
     Similar to smart_unicode, except that lazy instances are resolved to
@@ -48,7 +61,7 @@ def force_unicode(s, encoding='utf-8', strings_only=False, errors='strict'):
 
     If strings_only is True, don't convert (some) non-string-like objects.
     """
-    if strings_only and isinstance(s, (types.NoneType, int, long, datetime.datetime, datetime.date, datetime.time, float, Decimal)):
+    if strings_only and is_protected_type(s):
         return s
     try:
         if not isinstance(s, basestring,):