Don't crash if a CacheIndexable tries to clear a non-existent cache entry.

git-svn-id: http://svn.savannah.nongnu.org/svn/rdiff-backup@921 2b77aa54-bcbc-44c9-a7ec-4f6cf2b41109

trunk/rdiff-backup/CHANGELOG

+New in v1.2.1 (????/??/??)
+---------------------------
+
+Don't crash if a CacheIndexable tries to clear a non-existent cache entry,
+since the entry must already be cleared. (Andrew Ferguson)
+
+
 New in v1.2.0 (2008/07/27)
 ---------------------------
 

trunk/rdiff-backup/rdiff_backup/rorpiter.py

@@ -344,8 +344,12 @@ class CacheIndexable:
 		self.cache_dict[next_index] = next_elem
 		self.cache_indicies.append(next_index)
 
-		if len(self.cache_indicies) > self.cache_size: 
-			del self.cache_dict[self.cache_indicies[0]]
+		if len(self.cache_indicies) > self.cache_size:
+			try:
+				del self.cache_dict[self.cache_indicies[0]]
+			except KeyError:
+				log.Log("Warning: index %s missing from iterator cache" %
+					(first_index,),2)
 			del self.cache_indicies[0]
 
 		return next_elem