# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1422143738 -3600
# Node ID 86708cc73d28dbc3f3024b32c4c322f20a4eda92
# Parent  2f494c872a4c52460ce447281098be1e0ff65bc7
Since a new time point will divide an existing period, propagate the preceding
time point's period details.

diff -r 2f494c872a4c -r 86708cc73d28 imiptools/period.py
--- a/imiptools/period.py	Sun Jan 25 00:29:40 2015 +0100
+++ b/imiptools/period.py	Sun Jan 25 00:55:38 2015 +0100
@@ -226,8 +226,8 @@
 
     """
     Introduce into the 'slots' entries for those in 'points' that are not
-    already present, propagating active periods from time points preceding and
-    succeeding those added.
+    already present, propagating active periods from time points preceding
+    those added.
     """
 
     new_slots = []
@@ -237,18 +237,7 @@
         if i < len(slots) and slots[i][0] == point:
             continue
 
-        previously_active = i > 0 and slots[i-1] or []
-        subsequently_active = i < len(slots) and slots[i] or []
-
-        active = []
-
-        for p, s in zip(previously_active, subsequently_active):
-            if p == s:
-                active.append(p)
-            else:
-                active.append(None)
-
-        new_slots.append((point, active))
+        new_slots.append((point, i > 0 and slots[i-1][1] or []))
 
     for t in new_slots:
         insort_left(slots, t)