Updated SlugField to raise validation errors for invalid slugs

rest_framework/fields.py

@@ -389,10 +389,24 @@ class URLField(CharField):
 
 class SlugField(CharField):
     type_name = 'SlugField'
+    form_field_class = forms.SlugField
+    
+    default_error_messages = {
+        'invalid': _("Enter a valid 'slug' consisting of letters, numbers,"
+                     " underscores or hyphens."),
+    }
+    default_validators = [validators.validate_slug]
     
     def __init__(self, *args, **kwargs):
         super(SlugField, self).__init__(*args, **kwargs)
 
+    def __deepcopy__(self, memo):
+        result = copy.copy(self)
+        memo[id(self)] = result
+        #result.widget = copy.deepcopy(self.widget, memo)
+        result.validators = self.validators[:]
+        return result
+    
   
 class ChoiceField(WritableField):
     type_name = 'ChoiceField'

rest_framework/tests/fields.py

@@ -769,6 +769,21 @@ class SlugFieldTests(TestCase):
         self.assertEqual(serializer.is_valid(), True)
         self.assertEqual(getattr(serializer.fields['slug_field'], 'max_length'), 20)
 
+    def test_invalid_slug(self):
+        """
+        Make sure an invalid slug raises ValidationError
+        """
+        class SlugFieldSerializer(serializers.ModelSerializer):
+            slug_field = serializers.SlugField(source='slug_field', max_length=20, required=True)
+        
+            class Meta:
+                model = self.SlugFieldModel
+                
+        s = SlugFieldSerializer(data={'slug_field': 'a b'})
+        
+        self.assertEqual(s.is_valid(), False)
+        self.assertEqual(s.errors,  {'slug_field': ["Enter a valid 'slug' consisting of letters, numbers, underscores or hyphens."]})
+
 
 class URLFieldTests(TestCase):
     """