Subversion in multiuser environment with XCode 4.0

Question

I have been using XCode with subversion for some time now, no problem was caused when I was using it as a single developer (I was using 2 commands only, commit and add).

But now I have to share the code with another developer (who has never used any kind of version control) and integrating/merging the code has become a nightmare. No problem occur when we are integrating/merging .h/.m files but as soon as it comes to ".nib", "xcodeproj" and ".xcdatamodeld" files, we really don't know what to do.

Whenever we try to merge "xcodeproj", project was getting corrupt and merging ".xcdatamodeld" was kind of impossible for us.

So I was wondering if someone can share his/her experience on how to effectively use subversion/git/mercurial with XCode 4.0 in multiuser environment? or share a link, which can explain how to use subversion effectively in multiuser environment.

Thanks.

Answer 1

Are you doing this using Subversion? For 90% to 99% of the files in your repository, the standard Subversion workflow of checkout, edit, commit works well. However, for some types of files such as JPEGS and GIFS simply don't merge well. In this case, you'll have to do it the way we use to in the old SCCS and RCS days: Before you can edit and commit a file, you must lock it.

Locking a file prevents others from editing the same file and committing changes while you're doing your work on the file. It's crude, but it works. In Subversion, you can always lock any file you're editing, but if the file has the property svn:needs-lock on it, it will be checked out as read-only. You have to lock the file before editing it to make it writable, and you're not allowed to commit the file unless it is locked.

So, for those files, set the svn:needs-lock property on it.

You can automatically set this property on all newly added files (depending upon suffix) via setting the auto-properties in your Subversion client configuration.

And, if you really, really want to make sure that all .nibs and xcodeproj and all of the other flies of these types have svn:needs-lock set on them, you can use my pre-commit hook which will prevent these files from being committed unless this property is set.

Answer 2

I had the same problem with 2 other developers Xcode with git. Unfortunately, Xcode project files are an XML file, tracks file included in the project as well as setting. I'm not certain, but I think .nib files are also XML files as well. Someone can correct me on that.

Git did a great job at merging the Xcode project file, and never really had any problems with our *.nib files either. The only time we did have a problem is when we both added/removed files with the same names, or someone did a lot of heavy removing and adding of a lot of files.

The only way we solved this was to have each other push ann pull as soon as we added/removed files. So that way the person had the latest files, and didn't add them in their own repository then pull the latest commit which had the same file in it. Or they work adding changes to a file that was removed or renamed.

That is the best solution we found, as soon as we added or removed a file have everyone else in the team pull. Not a great solution btw. However, you should be committing often anyways.

Answer 3

There is no failsafe way to merge these kinds of files that I am aware of. So you will have to try to ensure that only one person is changing these files at a time. That won't work always, so just log what you changed in the file with the commit message. Then if there is a conflict, you can manually resolve it by taking the version that changed more of the file and redo manually what the other person did.

That's normally not a big deal, like adding a new source file to an .xcodeproject, or changing the alignment of an element in a .nib. It's becoming a problem if your project is huge or your nib is containing the whole interface. For it to work well (which in practice it does), you need to split up your projects into sub-projects if they grow too huge.