doc: fix up confusing doc comment

Differential Revision: https://phab.mercurial-scm.org/D6829

mercurial/bookmarks.py

@@ -480,8 +480,7 b' def comparebookmarks(repo, srcmarks, dst'
 
     Each elements of lists in result tuple is tuple "(bookmark name,
     changeset ID on source side, changeset ID on destination
-    side)". Each changeset IDs are 40 hexadecimal digit string or
-    None.
+    side)". Each changeset ID is a binary node or None.
 
     Changeset IDs of tuples in "addsrc", "adddst", "differ" or
      "invalid" list may be unknown for repo.

mercurial/exchange.py

@@ -730,9 +730,9 b' def _pushdiscoverybookmarks(pushop):'
     return _processcompared(pushop, ancestors, explicit, remotebookmark, comp)
 
 def _processcompared(pushop, pushed, explicit, remotebms, comp):
-    """take decision on bookmark to pull from the remote bookmark
+    """take decision on bookmarks to push to the remote repo
 
-    Exist to help extensions who want to alter this behavior.
+    Exists to help extensions alter this behavior.
     """
     addsrc, adddst, advsrc, advdst, diverge, differ, invalid, same = comp