Correct issue iamteem#20 from original fork iamteem#20 (thanks to @ja…

…kepic1)

redisco/models/attributes.py

@@ -5,7 +5,7 @@
 import time
 from datetime import datetime, date
 from redisco.containers import List
-from exceptions import FieldValidationError
+from exceptions import FieldValidationError, MissingID
 
 __all__ = ['Attribute', 'CharField', 'ListField', 'DateTimeField',
         'DateField', 'ReferenceField', 'IntegerField',
@@ -110,9 +110,15 @@ def validate(self, instance):
 
     def validate_uniqueness(self, instance, val):
         encoded = self.typecast_for_storage(val)
-        same = len(instance.__class__.objects.filter(**{self.name: encoded}))
-        if same > 0:
-            return (self.name, 'not unique',)
+        matches = instance.__class__.objects.filter(**{self.name: encoded})
+        if len(matches) > 0:
+            try:
+                instance_id = instance.id
+                no_id = False
+            except MissingID:
+                no_id = True
+            if (len(matches) != 1) or no_id or (matches.first().id != instance.id):
+                return (self.name, 'not unique',)
 
 
 class CharField(Attribute):
@@ -127,12 +133,12 @@ def validate(self, instance):
             super(CharField, self).validate(instance)
         except FieldValidationError as err:
             errors.extend(err.errors)
-        
+
         val = getattr(instance, self.name)
-          
+
         if val and len(val) > self.max_length:
             errors.append((self.name, 'exceeds max length'))
-        
+
         if errors:
             raise FieldValidationError(errors)
 
@@ -375,7 +381,7 @@ def attname(self):
 
     @property
     def related_name(self):
-        return self._related_name 
+        return self._related_name
 
     def validate(self, instance):
         val = getattr(instance, self.name)