# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@octobus.net>
# Date 1551877647 -3600
# Node ID 3f3f962457b20f9570e0b676a83ccc984ed27125
# Parent  9e737ca539f6878a14d5b10a78eb8abf1574bbf2
revlog: add some documentation to the `checksize` method

I had to look at it, so I figured I would leave some documentation for the next
person seeking information.

diff -r 9e737ca539f6 -r 3f3f962457b2 mercurial/revlog.py
--- a/mercurial/revlog.py	Wed Mar 06 12:20:50 2019 +0100
+++ b/mercurial/revlog.py	Wed Mar 06 14:07:27 2019 +0100
@@ -2272,6 +2272,14 @@
         self._nodepos = None
 
     def checksize(self):
+        """Check size of index and data files
+
+        return a (dd, di) tuple.
+        - dd: extra bytes for the "data" file
+        - di: extra bytes for the "index" file
+
+        A healthy revlog will return (0, 0).
+        """
         expected = 0
         if len(self):
             expected = max(0, self.end(len(self) - 1))