diff -r 9060af281be7 -r a87ca1d7e61d mercurial/branchmap.py
--- a/mercurial/branchmap.py	Mon Feb 04 19:46:57 2019 +0100
+++ b/mercurial/branchmap.py	Mon Feb 11 16:34:48 2019 +0300
@@ -45,7 +45,7 @@
 
 
 class BranchMapCache(object):
-    """Cache mapping"""
+    """mapping of filtered views of repo with their branchcache"""
     def __init__(self):
         self._per_filter = {}