What is the proper way to do a Subversion merge in Eclipse?

Question

I\'m pretty used to how to do CVS merges in Eclipse, and I\'m otherwise happy with the way that both Subclipse and Subversive work with the SVN repository, but I\'m not quite su

Answer 1

I would advise not trying to use Eclipse's plugins as your primary access to Subversion.

If you are developing on Windows, TortoiseSVN is the best program that I have seen for Subversion access. Explore to the directory of which you wish to merge, right click on it and use the Tortoise SVN merge option. Assuming a non-interactive merge, once you get conflicts, you'll have to go through each conflicted file and edit the conflicts before marking them as resolved. For this process I recommend a program called KDiff3, which shows your local repository copy (what was stored in the .svn before the merge), your local copy (including any changes), and the copy coming from the repository, and allows you to easily see (and even hand-modify if needed) the result of the merging. It also handles a bunch of minor conflicts automatically.

KDiff3 is portable, TortoiseSVN is a windows shell extension, so if you're using another environment, I would try to just use SVN to merge. But that would be much more of a pain :)

Answer 2

I typically check out both branches and then use the compare to each other option which does a synchronize-like compare of the two source trees. After integrating the changes into one branch, you can recommit back to the repository.

Answer 3

Remember that with svn reverting a modified tree to a clean state is fairly easy. Simply have a clean workspace on the merge destination branch and run the merge command to import the modifications from the merge source branch, then synchronize your workspace and you will get your usual eclipse comparison window showing all the merge modified files and the conflicts.

If for some reason you can't solve the conflicts you can svn revert on the project and go back to a clean state, otherwise you do the merge in place and once you are done you can commit. Note that you don't have to commit, once you are done handling the conflicts you can also return to the dev view, verify that the code compiles, run your unit tests, whatever and then synchronize again and commit (once the conflict are locally resolved they won't come back)

last time I looked, when you use subclipse merge command it will overwrite the merged file (using conflict markers to show conflicting areas) and put the original left and right side of the merge in the same place. it shouldn't put anything in different directories.

As a rule of thumb, it is best to commit all merge modifications in a single commit and to only have the merge modifications in the commit so that you can rollback the merge later if needed.

Answer 4

Merging an entire branch into trunk

1. Inspect the Branch project history to determine the version from which the branch was taken

   • by default Eclipse Team "History" only shows the past 25 revisions so you will have to click the button in that view labeled "Show All"
   • when you say "Show All" it will take you back past the branch date and show you all the history for trunk as well so you'll have to search for your comment where you branched
   • NOTE: if you use Tortise SVN for this same task (navigate to the branch and select "Show Log") it will show you only the branch history so you can tell exactly where the branch began

2. So now I know that 82517 was the first version ID of the branch history. So all versions of the branch past 82517 have changes that I want to merge into trunk

3. Now go to the "trunk" project in your Eclipse workspace and select "right click - Team - Merge"

4. The default view is the 1 url merge

   • select the URL of the branch from which you are merging
   • under Revisions select "All"
   • press OK

5. This will take you to the "Team Synchronizing" perspective (if it doesn't you should go there yourself) in order to resolve conflicts (see below)

Re-Merging more branch changes into trunk

1. Insepct the trunk project history to determine the last time you merged into trunk (you should have commented this)

   • for the sake of argument let's say this version was 82517

2. So now I know that any version greater than 82517 in the branch needs to be merged into trunk

3. Now go to the "trunk" project in your Eclipse workspace and select "right click - Team - Merge"

4. The default view is the 1 url merge

   • select the URL of the branch from which you are merging
   • under Revisions select "Revisions" radio button and click "Browse"
   • this will open up a list of the latest 25 branch revisions
   • select all the revisions with a number greater than 82517
   • press OK (you should see the revision list in the input field beside the radio button)
   • press OK

5. This will take you to the "Team Synchronizing" perspective (if it doesn't you should go there yourself) in order to resolve conflicts (see below)

Resolving Conflicts

1. You should be at the "Team Synchronizing" perspective. This will look like any regular synchronization for commit purposes where you see files that are new and files that have conflicts.

2. For every file where you see a conflict choose "right click - Edit Conflicts" (do not double click the file, it will bring up the commit diff version tool, this is VERY different)

   • if you see stuff like "<<<<<<< .working" or ">>>>>>> .merge-right.r84513" then you are in the wrong editing mode

3. once you have resolved all the conflicts in that file, tell the file to "mark as merged"

4. once all the files are free of conflicts you can then synchronize your Eclipse project and commit the files to SVN

Answer 5

Use Eclipse integration, it works perfectly fine.

The main change from CVS, is that you only merge deltas from a branch, ie changes from one revision to another. That is to say you have to track the correct start revision somehow (unless you have svn 1.5 merge history)

If you got that right, it's only up to you to get the changes right with the compare editor.

Answer 6

openCollabNet's merge tool for subclipse is pretty neat. There are many merging types available and the merging I just performed with it when seamlessly. I recommend it.