Example python session:
>>> from django.core.defaultfilters import slugify
>>> slugify('Django Rocks!', None)
'django-rocks'
>>> slugify('django-rocks', None)
'djangorocks'
Personally, I think it makes much more sense to not have it remove the hyphens. Basically, you want slugify(slugify(slugify(X))) to equal slugify(X).
The simple fix here is the following diff
Index: defaultfilters.py
===================================================================
--- defaultfilters.py (revision 463)
+++ defaultfilters.py (working copy)
@@ -54,7 +54,7 @@
def slugify(value, _):
"Converts to lowercase, removes non-alpha chars and converts spaces to hyphens"
- value = re.sub('[^\w\s]', '', value).strip().lower()
+ value = re.sub('[^\w\s-]', '', value).strip().lower()
return re.sub('\s+', '-', value)
def stringformat(value, arg):
