# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1438536556 -7200
# Node ID 14b3142e5870eb506402b7b684f5b2f23c364fa3
# Parent  ad99cd241c8f90d0f002adb0d7f67885f79dff1d
Fixed access to absent rule parameters.

diff -r ad99cd241c8f -r 14b3142e5870 imiptools/data.py
--- a/imiptools/data.py	Sun Aug 02 14:46:09 2015 +0200
+++ b/imiptools/data.py	Sun Aug 02 19:29:16 2015 +0200
@@ -595,7 +595,7 @@
     """
 
     rrule = obj.get_value("RRULE")
-    parameters = get_parameters(rrule)
+    parameters = rrule and get_parameters(rrule)
 
     # Use localised datetimes.
 
@@ -619,7 +619,7 @@
     if not rrule:
         periods = [RecurringPeriod(dtstart, dtend, tzid, "DTSTART", dtstart_attr, dtend_attr)]
 
-    elif end or parameters.has_key("UNTIL") or parameters.has_key("COUNT"):
+    elif end or parameters and parameters.has_key("UNTIL") or parameters.has_key("COUNT"):
 
         # Recurrence rules create multiple instances to be checked.
         # Conflicts may only be assessed within a period defined by policy