[#2375] ckan jinja2 truncate filter override

ckan/config/environment.py

@@ -305,6 +305,7 @@ def genshi_lookup_attr(cls, obj, key):
     env.install_gettext_callables(_, N_, newstyle=True)
     # custom filters
     env.filters['empty_and_escape'] = lib.jinja_tags.empty_and_escape
+    env.filters['truncate'] = lib.jinja_tags.truncate
     config['pylons.app_globals'].jinja_env = env
 
     # CONFIGURATION OPTIONS HERE (note: all config options will override

ckan/lib/jinja_tags.py

@@ -5,6 +5,7 @@
 from jinja2.ext import Extension
 from jinja2.exceptions import TemplateNotFound
 from jinja2.utils import open_if_exists, escape
+from jinja2.filters import do_truncate
 
 import lib.base as base
 import lib.helpers as h
@@ -19,6 +20,17 @@ def empty_and_escape(value):
     else:
         return escape(value)
 
+def truncate(value, length=255, killwords=None, end='...'):
+    ''' A more clever truncate. If killwords is supplied we use the default
+    truncate.  Otherwise we try to truncate using killwords=False, if this
+    truncates the whole value we try again with killwords=True '''
+    if killwords is not None:
+        return do_truncate(value, length=length, killwords=killwords, end=end)
+    result = do_truncate(value, length=length, killwords=False, end=end)
+    if result != end:
+        return result
+    return do_truncate(value, length=length, killwords=True, end=end)
+
 ### Tags
 
 class CkanExtend(Extension):