Ticket #3982: coerce.diff

django/db/models/fields/__init__.py

@@ -140 +140 @@
         cls._meta.add_field(self)
         if self.choices:
             setattr(cls, 'get_%s_display' % self.name, curry(cls._get_FIELD_display, field=self))
+        if hasattr(self, 'coerce'):
+            dispatcher.connect(self._force_coercion, signal=signals.post_init, sender=cls)
 
+    def _force_coercion(self, sender, instance, signal, *args, **kwargs):
+        value = self.coerce(getattr(instance, self.attname))
+        setattr(instance, self.attname, value)
+
     def get_attname(self):
         return self.name