sort/group by missing values correctly [SF#1198623]

Author: Richard Jones

CHANGES.txt

@@ -26,6 +26,7 @@ Fixed:
   popups (sf bug 1211800)
 - handle dropped properies in rdbms/metakit journal export (sf bug 1203569)
 - handle missing Subject lines better (sf bug 1198729)
+- sort/group by missing values correctly (sf bug 1198623)
 
 
 2005-05-02 0.8.3

doc/index.txt

@@ -146,6 +146,7 @@ Maciej Starzyk,
 Mitchell Surface,
 Mike Thompson,
 Michael Twomey,
+Karl Ulbrich,
 Martin Uzak,
 Darryl VanDorp,
 J Vickroy,

roundup/cgi/templating.py

@@ -2341,8 +2341,11 @@ def propchanged(self, property):
         ''' Detect if the property marked as being the group property
             changed in the last iteration fetch
         '''
+        # we poke directly at the _value here since MissingValue can screw
+        # us up and cause Nones to compare strangely
         if (self.last_item is None or
-                self.last_item[property] != self.current_item[property]):
+                self.last_item[property]._value !=
+                self.current_item[property]._value):
             return 1
         return 0