Version 5 (modified by 15 years ago) ( diff ) | ,
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Managing HelenOS source with Bazaar
This should help you to start using our new VCS, Bazaar. Please read this little guide carefully. Inappropriate use of Bazaar WILL make a mess in our repository. This page only documents how to use Bazaar with HelenOS. If you are confused and want to know what happens behind the scenes, read the Bazaar Theory.
Linear History
If you are doing a simple change (or several simple, unrelated changes) you might try to go for linear history. This will only work if nobody else pushed any changes to the main repository while you were doing your changes. Start by creating your private branch:
$ bzr branch bzr://bzr.helenos.org/head my_branch
This will create a branch (and working copy) under the directory my_branch
. Now make some changes and commit them to your private branch:
$ cd my_branch my_branch$ ...modify some files... my_branch$ bzr commit -m "Fixed crash when writing zero bytes to FAT."
Now we can try and push back our changes to the main repository:
my_branch$ bzr push --remember bzr+http://jermar@bzr.helenos.org/head
In the command above please replace jermar
with your username. Next time you can just use
my_branch$ bzr push
If nobody pushed any changes since the point you branched off, this will work. Otherwise it will fail. If it fails like this:
...
you have two options. Either rebase your changes to the mainline head or switch to structured history workflow.
Rebasing
Structured History
Stuctured history is good. If you are working on some feature and produce several related commits, it is better to group them to a separate branch. Also, with Bazaar it is not uncommon to have long-running branches (that are merged after weeks, months). Do not be afraid of structured history.
If your branch diverged from the mainline (i.e. somebody pushed to the main repository since you branched off), you cannot push anymore. You must merge the two branches. With merging, the order of arguments is significant. You must always merge your branch into the mainline, never the other way around! How can you do this? With bazaar you can only merge to a local repository (you need to chdir into it), you cannot merge to a remote repository.
Therefore we have to resort to a little trick. Suppose your branch my_branch
diverged from the mainline. We thus create a new branch head_clone
which will be a clone of the mainline:
$ bzr branch bzr://bzr.helenos.org/head head_clone
Now go to the clone repository and merge your branch into it:
$ cd head_clone head_clone$ bzr merge ../my_branch
Now we can push from the clone to the main repository:
head_clone$ bzr push bzr+http://jermar@bzr.helenos.org/head
Finally let us sync our branch with the main repository:
head_clone$ cd ../my_branch my_branch$ bzr pull
Again, the push might have failed if somebody else pushed since you created your head_clone
. In that case probably the best idea is to try and rebase your merge commit to the new mainline head.