Hg convert loses branches - mercurial

I'm trying to convert a Mercurial repository to move all the files into a subdirectory in preparation for merging two repositories into one. The problem that I am having is that some of my branches are being lost in the conversion process.
This is what I am doing:
hg convert --filemap filemap.txt SourceRepo DestRepo
My filemap.txt is as follows:
rename . subdir
When this command completes, DestRepo is missing all branches of SourceRepo that were created but which had no changes made to them.
The reason why I have branches that are exactly the same as the parent is because the original repository was an SVN repository so we used branches to tag versions.
Is there any way that I can complete this conversion without losing the branches?
EDIT: Answering Ry4n's question.
The source repo is a Mercurial repository which was created from an SVN repository using the hgsubversion extension.
Here is a log of the branch:
> hg log -b V3.02.55
changeset: 84:cf19dfac555c
branch: V3.02.55
parent: 71:aec56bf6ad9a
user: steve.kaye#868e8ea5-81c6-0a4c-a81c-ce52fb006997
date: Wed Aug 24 15:31:01 2011 +0000
summary: Branching V3.02.55

In Mercurial there is no such thing as a named branch with no changes on them. If your source repo is a Mercurial repository it either doesn't have those named branches or they have at least one change on them.
Is your source Mercurial?
If so, Can you provide the hg log -b NAME output for one of the branches you think exists but has no changes?

Related

Add a parent to the original changeset in Mercurial

I have a project with 24 months of source control history in a Mercurial repository.
I've recently found some old tarballs of the project that predate source control, and i think they would be useful to import into the repository as "pre-historic" changesets.
Can i somehow add a parent to my initial commit?
Alternatively, is it possible to re-play my entire repository history on top of the tarballs, preserving all metadata (timestamps etc)?
Is it possible to have the new parent commits use the timestamps of these old tarballs?
You can use the convert extension to build a new repository where the tarballs are imported as revisions before your current root revision.
First, you import the tarballs based on the null revision:
$ hg update null
$ tar -xvzf backup-2010.tar.gz
$ hg addremove
$ hg commit -m 'Version from 2010'
$ rm -r *
$ tar -xvzf backup-2011.tar.gz
$ hg addremove
$ hg commit -m 'Version from 2011'
I'm using addremove above to give Mercurial a chance to detect renames between each tarball (look at the --similarity flag to fine-tune this and use hg rename --after by hand to help Mercurial further). Also, I remove all the files in the working copy before importing a new tarball: that way the next commit will contain exactly the snapshot present in the tarball you unpack.
After you've imported all the tarballs like above, you have a parallel history in your repository:
[c1] --- [c2] --- [c3] ... [cN]
[t1] --- [t2] --- [tM]
Your old commits are c1 to cN and the commits from the tarballs are t1 to tM. At the moment they share no history — it's as if you used hg pull -f to pull an unrelated repository into the current one.
The convert extension can now be used to do a Mercurial to Mercurial conversion where you rewrite the parent revision of c1 to be tM. Use the --splicemap flag for this. It needs a file with
<full changeset hash for c1> <full changeset hash for tM>
Use hg log --template '{node} ' -r c1 -r tM > splicemap to generate such a file. Then run
$ hg convert --splicemap splicemap . spliced
to generate a new repository spliced with the combined history. The repository is new, so you need to get everybody to re-clone it.
This technique is similar to using hg rebase as suggested by Kindread. The difference is that convert wont try to merge anything: it simply rewrites the parent pointer in c1 to be tM. Since there is no merging involved, this cannot fails with weird merge conflicts.
You should look at using rebase. This can allow you to make the changes the 2nd changeset on your repo ( you have to rebase from the 1st ).
https://www.mercurial-scm.org/wiki/RebaseExtension
However, note that if there are other clones of this repo existing ( such as for fellow developers, or on a repo server ), you will have issues with them pulling the revised repo. You will probably have to co-ordinate with the owners of those clone's to get all work into a single clone, rebase that clone, and then have everyone re-clone from the revised clone. You will also have to change the phase the of the changesets.
https://www.mercurial-scm.org/wiki/Phases
Honestly though, I would just add them to your 'modern-day' repo, I don't think making them pre-historic would give you any notable advantage over adding them to the top.

Mercurial requiring manual merges unexpectedly

I've got a project running under Mercurial and am finding a lot of situations where a file needs manually merging, when I believe it should be able to merge automatically. I am wondering whether there are any options that can be given to Mercurial to help it out in these areas.
The project has an underlying platform with a couple of hundred files that can't be edited on the project. When the platform is updated, the project gets updated versions of these core files outside of Mercurial. The sequence I'm seeing repeatedly is:
On central dev system (linked to the core platform update mechanism):
Get a new version of core platform.
Commit these changes e.g. hg commit -m "New platform release"
Push to central mercurial server
On my Linux box:
Commit local changes
Pull from central mercurial server, and try to merge
Find merge conflicts on core files
The last two core files I've had to merge have no changes between the base and local versions (the access time is updated during a build, but the content is the same). The only changes are on the remote revision I'm merging with.
The only non-standard configuration I'm aware of is that the central mercurial instance is running under Rhodecode, with a commit hook setup to update a Redmine repository.
Is there anything else that can be configured in mercurial to help it figure out merges?
You can redo a merge with --debug to get more information about a merge. That is, take your repository and do
$ cd ..
$ hg clone my-project -r 123 -r 456 merge-test
where 123 and 456 is the two parents of the merge you want to examine closer. Then run
$ hg merge --debug
to see what Mercurial says. It should look like this if the file foo has only been changed in the branch you're merging in:
$ hg merge --debug
searching for copies back to rev 2
resolving manifests
overwrite: False, partial: False
ancestor: 932f5550d0ce, local: b0c286a4a76d+, remote: c491d1593652
foo: remote is newer -> g
updating: foo 1/1 files (100.00%)
getting foo
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
Here I was on revision b0c286a4a76d and merged with c491d1593652.
You can also use
$ hg status --rev "ancestor(b0c286a4a76d, c491d1593652)" --rev "c491d1593652"
M foo
$ hg status --rev "ancestor(b0c286a4a76d, c491d1593652)" --rev "b0c286a4a76d"
M bar
to double-check which files have been changed between the ancestor revision and the two changesets you're merging. Above you see that I changed foo on one branch and bar on the other.
If you see a platform file appear in both status lists, well then something went wrong in your procedures and this can explain the merge conflicts.
If this isn't enough to figure out what went wrong, then I suggest asking this question on the Mercurial mailinglist. That's a great place for discussion and bug-hunting — much better than Stack Overflow.

Mercurial merge branches? (abort: push creates new remote branches)

I'm new to Mercurial, and I made the mistake of making different changes on different systems before the main repository was up to date. (I understand this is what Mercurial is built for, but my thick brain is struggling to resolve the issue.)
Now on my primary development server, everything is up to date and committed. However...
$ hg push
abort: push creates new remote branches: 4f2672f039d7!
(use 'hg push --new-branch' to create new remote branches)
I don't really want a new branch. I just want all the changes to be merged.
$ hg heads
changeset: 459:ff5f94e44aba
branch: 4f2672f039d7
tag: tip
parent: 458:e63d02baf4cf
parent: 455:267abda62069
user: mike#...
date: Tue Sep 13 14:25:16 2011 -0400
summary: Images from prof
changeset: 455:267abda62069
parent: 453:a74757e26357
user: mike#localhost.localdomain
date: Tue Sep 13 09:08:12 2011 -0400
summary: images for FLC
Point me in the right direction?
EDIT: (adding detail)
When I try to merge, I get the following result:
$ hg merge
abort: branch '4f2672f039d7' has one head - please merge with an explicit rev
(run 'hg heads' to see all heads)
I have tried hg merge ff5f94e44aba, and all of the revs listed above, and each one returns the same result:
$ hg merge 267abda62069
abort: merging with a working directory ancestor has no effect
It looks like you've accidentally created a branch with a silly name. What you most likely want to do is reapply your changes with a branch name that makes better sense. There's no totally automatic way of doing this, but you can extract each changeset as a patch, revert to the point where you messed up and reapply those changes on the proper branch.
Basically what you need to do is look at the changelog; probably by running hg out to see what's missing from the central repository. Make a note of each of the revs that you want to keep.
Next update to the last good revision. Make sure that you are on the branch you wanted your commits to be on.
Now you will apply each of the changes you made and commit each one. You can automate this process something like this:
BADREVS="123 124 125 126"
recommit() { hg di -c $1 | patch -p1; hg ci -m "$(hg log -r $1 --template '{desc}')";}
for rev in $BADREVS; do
recommit $rev
done
Now you've got your changes in your local repository twice; once as the commits on the weird branch and again on the right branch. You can push those changes to the central repo using hg push -b GOODBRANCH so that only the changes to the right branch go up; Alternatively, you can install the strip extension to remove the changes you didn't want from the local repo and then you can push as normal.
By the sound of it; you will still have to deal with the changes made to the central repository before you can push, since you pushed changes from another repo. You probably want to do this merging after you clean up the change history in the local repo.
Pull from remote and then update / merge / commit first. Then you won't make new branches.
I've had this happen when I missed a merge. I like the TortoiseHg workbench for this because it can be a little easier to find what you missed through visualization.
A good way to avoid this in the future, how I stopped getting this error, is the fetch extension. Set your post pull to fetch and it will automatically merge for you, which is very nice. If there's a conflict it brings up whatever conflict resolver you use.

Mercurial managing multiple repositories

We have a repository myproject - as the repo is nearly ready for release we are creating myproject-1_0. Version 2 dev will continue in myproject while minor tweaks and bug fixes will go in myproject-1_0. What is the best way to merge myproject-1_0 changes into myproject?
Is this the best approach:
$ cd myproject
$ hg pull ../myproject-1_0
$ hg merge
$ hg commit -m 'Merge bugfix from 1.0 branch'
$ hg push
?
What would happen if we did this merge on Feb 1st, then we made more changes in myproject-1_0? Would we follow the steps again and the hg pull ../myproject-1_0 would just pull the changesets done after the pull on Feb 1st?
In the myproject repo, is there a way to do an hg log and determine which changesets came from myproject-1_0 and which ones came from myproject?
Are there any other recommendations about this general approach?
Questions in sequence:
Is this the best approach? - yes, unless you want to use named branches and keep everything in one repository
would just pull the changesets done after the pull on Feb 1st? - yes
is there a way to do an hg log and determine which changesets came from myproject-1_0? - no
Unfortunately, unless you start mucking about with named branches, changesets that originate in the other repository looks no different from the ones in your main repository.
So this is what Mercurial is designed to do
I would suggest taking a look at http://www.hginit.com. But what you're asking if when you pull changes will it only pull the changes since the last pull, yes. You can't tell which changesets came from a different clone though, only user names are tracked in the idea that you are thinking about.
If you want to know where things are coming from this is something you can do in commit messages.

How to apply a collapsed revisions patch to trunk in Mercurial?

I am looking for best practices to do the following:
When I need to implement a feature or fix a bug, I am creating new Mercurial repository from the main one (a trunk).
Then, within some days, or weeks, I am implementing the task in newly created repository, making commits and periodically merging with trunk. After the code in new repository will pass all code reviews, I should provide a repository with all changes collapsed into single revision.
My common way to do this (rdiff extension should be enabled):
hg clone ~/repos/trunk ~/repos/new-collapsed
cd ~/repos/new-collapsed
hg diff ~/repos/new > new.diff
patch -p1 < new.diff
hg commit
This works almost well except when there are binary files present in the changes from ~/repos/new. Another way could be:
hg clone ~/repos/trunk ~/repos/new-collapsed
cd ~/repos/new-collapsed
hg pull ~/repos/new
hg update
hg rollback
then resolve possible conflicts and manually commit the changes
Both ways look for me somewhat ugly and non-native, so I am looking how this operation could be simplified. I've played with rebase extension, but seems its hg rebase --collapse command does not work with workflow described above.
Any ideas are welcome.
Sounds like a good case for mercurial queues.
I do something similar with the histedit extension.
My workflow is something like:
clone a central repo
commit incremental changes to local repo
clone my local repo to make collapsed repo
hg histedit and select/discard/fold the revisions as needed
hg push the collapsed repo to central repo
pull central repo to local or refresh local from scratch
I ensure that my local repo never gets pushed to the central repo by adding an invalid default-push path to the .hg/hgrc file in the local repo root directory.
Solved: Just add
[diff]
git = True
to your hgrc file, and then use my first solution with rdiff extension, replacing patch with hg import:
hg clone ~/repos/trunk ~/repos/new-collapsed
cd ~/repos/new-collapsed
hg diff ~/repos/new > new.diff
hg import new.diff
hg commit