updating working directory
2 files updated, 0 files merged, 0 files removed, 0 files unresolved

% Now b has one revision to be pulled from a
pulling from 
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
saving bundle to 
adding branch
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
rebase completed
@  3:L1
|
o  2:R1
|
o  1:C2
|
o  0:C1


% Re-run pull --rebase
pulling from 
searching for changes
no changes found

% Invoke pull --rebase with --update
abort: --update and --rebase are not compatible