changegroup() has a problem when nodes which does not descend from a node
in <bases> are added to remote after the discovery phase.
If that happens, changegroup() won't send the correct set of nodes, ie.
some nodes will be missing.
To correct it we have to find the set of nodes that both remote and self
have (called <common>), and send all the nodes not in <common>.
This fix has some overhead, in the worst case it will re-send a whole branch.
A proper fix to avoid this overhead might be to change the protocol so that
the <common> nodes are sent (instead of the <bases> of the missing nodes).
With this change, "hg clone" looks like this:
% hg clone http://example.com/repo/big big
requesting all changes
adding changesets
adding manifests
adding file changes
added XXX changesets with XXX changes to XXX files
updating working directory
XXX files updated, XXX files merged, XXX files removed, XXX files unresolved
So the user sees
% hg clone http://example.com/repo/big big
requesting all changes
adding changesets
adding manifests
adding file changes
added XXX changesets with XXX changes to XXX files
updating working directory
while Mercurial is writing to disk to populate the working directory
With this change, "hg clone" looks like this:
% hg clone big big-work
updating working directory
XXX files updated, XXX files merged, XXX files removed, XXX files unresolved
Use case: If a remote repo has two heads and I _want_ to merge them, I merge
and push. Meanwhile someone else pushed on top of one of the heads. He won't
get a warning, because he doesn't create a new head, I won't notice that I
don't close a head, because I don't get a message telling me.
(including small changes to revert and backout to not show these stats
with the exception of backout --merge)
Show update stats (unless -q), e.g.:
K files updated, L files merged, M files removed, N files unresolved
Inform the user what to do after a merge:
(branch merge, don't forget to commit)
Inform the user what to do if a branch merge failed:
There are unresolved merges, you can redo the full merge using:
hg update -C X
hg merge Y
Inform the user what to do if a working directory merge failed:
There are unresolved merges with locally modified files.
Fixing issue179.
The algorithm checks if there not more new heads on the remote side than heads
which become non-heads due to getting children.
Pushing this repo:
m
/\
3 3a|
|/ /
2 2a
|/
1
to a repo only having 1, 2 and 3 didn't abort requiring --force before.
Added test cases for this and some doc strings for used methods.
repo.addchangegroup method now returns number of heads modified and added,
so command line can tell whether update or merge needed. this makes
tiny change to ssh wire protocol, but change is backwards compatible.
pull command now returns 0 if no changes to pull.
Since switching to the multihead approach, we've been creating
excessive file-level merges where files are marked as merged with
their ancestors.
This explicitly checks at commit time whether the two parent versions
are linearly related, and if so, reduces the file check-in to a
non-merge. Then the file is compared against the remaining parent,
and, if equal, skips check-in of that file (as it's not changed).
Since we're not checking in all files that were different between
versions, we no longer need to mark so many files for merge. This
removes most of the 'm' state marking as well.
Finally, it is possible to do a tree-level merge with no file-level
changes. This will happen if one user changes file A and another
changes file B. Thus, if we have have two parents, we allow commit to
proceed even if there are no file-level changes.