# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1513033522 -3600
# Node ID 05de61cc499f715c89a3bbb784122cb7331674dd
# Parent  0249f30178a473d815421afa6ccbc84f1549582b
Made period classification use unedited rather than stored periods.

diff -r 0249f30178a4 -r 05de61cc499f imiptools/editing.py
--- a/imiptools/editing.py	Mon Dec 11 22:09:38 2017 +0100
+++ b/imiptools/editing.py	Tue Dec 12 00:05:22 2017 +0100
@@ -401,26 +401,16 @@
 
         "Classify changes in the updated periods for the edited event."
 
-        updated = self.combine_periods_for_comparison()
-        return classify_period_changes(updated)
+        return classify_period_changes(self.combine_periods())
 
     def classify_periods(self):
 
         "Classify the updated periods for the edited event."
 
-        updated = self.combine_periods()
-        return classify_periods(updated)
+        return classify_periods(self.combine_periods())
 
     def combine_periods(self):
 
-        "Combine stored and checked edited periods to make updated periods."
-
-        stored = self.get_stored_periods()
-        current = self.get_checked_periods()
-        return combine_periods(stored, current)
-
-    def combine_periods_for_comparison(self):
-
         "Combine unedited and checked edited periods to make updated periods."
 
         original = self.state.get_original("periods")
@@ -1207,8 +1197,9 @@
 def periods_from_updated_periods(updated_periods, fn):
 
     """
-    Return periods from the given 'updated_periods' created using 'fn', setting
-    replacement, cancelled and recurrence identifier details.
+    Return periods from the given 'updated_periods' having the form (stored,
+    unedited), creating them using 'fn', and setting replacement, cancelled and
+    recurrence identifier details.
 
     This function should be used to produce editing-related periods from the
     general updated periods provided by the client abstractions.
@@ -1244,9 +1235,21 @@
     return periods
 
 def event_periods_from_updated_periods(updated_periods):
+
+    """
+    Return event periods from the 'updated_periods' having the form (stored,
+    unedited).
+    """
+
     return periods_from_updated_periods(updated_periods, event_period_from_period)
 
 def form_periods_from_updated_periods(updated_periods):
+
+    """
+    Return form periods from the 'updated_periods' having the form (stored,
+    unedited).
+    """
+
     return periods_from_updated_periods(updated_periods, form_period_from_period)
 
 def periods_by_recurrence(periods):
@@ -1271,7 +1274,8 @@
 
     """
     Combine 'old' and 'new' periods for comparison, making a list of (old, new)
-    updated period tuples.
+    updated period tuples. Such tuples encode correspondences between periods
+    representing the same, potentially-edited data.
     """
 
     old_by_recurrenceid, _new_periods = periods_by_recurrence(old)
@@ -1302,10 +1306,10 @@
 
     return combined
 
-def classify_periods(updated_periods):
+def classify_periods(edited_periods):
 
     """
-    Using the 'updated_periods', being a list of (stored, current) periods,
+    Using the 'edited_periods', being a list of (unedited, edited) periods,
     return a tuple containing collections of new, replaced, retained, cancelled
     and obsolete periods.
 
@@ -1323,24 +1327,24 @@
     cancelled = []
     obsolete = []
 
-    for sp, p in updated_periods:
+    for op, p in edited_periods:
 
-        # Stored periods...
+        # Unedited periods that are not cancelled.
 
-        if sp:
+        if op and not op.cancelled:
 
             # With cancelled or absent current periods.
 
             if not p or p.cancelled:
-                cancelled.append(sp)
+                cancelled.append(op)
 
             # With differing or replacement current periods.
 
-            elif p != sp or p.replacement:
+            elif p != op or p.replacement:
                 replaced.append(p)
                 if not p.replacement:
                     p.new_replacement = True
-                    obsolete.append(sp)
+                    obsolete.append(op)
 
             # With retained, not differing current periods.
 
@@ -1349,17 +1353,17 @@
                 if p.new_replacement:
                     p.new_replacement = False
 
-        # New periods without corresponding stored periods.
+        # New periods without corresponding unedited periods.
 
         elif p:
             new.append(p)
 
     return new, replaced, retained, cancelled, obsolete
 
-def classify_period_changes(updated_periods):
+def classify_period_changes(edited_periods):
 
     """
-    Using the 'updated_periods', being a list of (original, current) periods,
+    Using the 'edited_periods', being a list of (unedited, edited) periods,
     return a tuple containing collections of modified, unmodified and removed
     periods.
     """
@@ -1368,7 +1372,7 @@
     unmodified = []
     removed = []
 
-    for op, p in updated_periods:
+    for op, p in edited_periods:
 
         # Test for periods cancelled, reinstated or changed, or left unmodified
         # during editing.