misc: use Truncator in ellipsize (#42744)

wcs/qommon/misc.py

@@ -39,10 +39,11 @@ from django.utils import datetime_safe
 from django.utils import six
 from django.utils.encoding import force_text
 from django.utils.html import strip_tags
-from django.template import engines, TemplateSyntaxError, VariableDoesNotExist
+from django.template import TemplateSyntaxError, VariableDoesNotExist
 from django.utils.six.moves.html_parser import HTMLParser
 from django.utils.six.moves.urllib.parse import quote, urlencode
 from django.utils.six.moves.urllib import parse as urlparse
+from django.utils.text import Truncator
 
 from quixote import get_publisher, get_response, get_request, redirect
 from quixote.html import htmltext
@@ -263,7 +264,7 @@ def ellipsize(s, length=30):
     s = force_text(s, get_publisher().site_charset, errors='replace')
     if s and len(s) > length:
         if length > 3:
-            s = s[:length-3] + '(…)'
+            s = Truncator(s).chars(length, truncate='(…)')
         else:
             s = s[:length]
     return force_str(s)