I have been investigating any potential issues encountered when merging branches in TFS 2010.
All combinations which I have tried have worked perfectly, apart from one, and I am hoping that someone can help me understand why it is not working and/or what I am doing incorrectly.
It is perfectly reproducible, and I have described how below.
The problem scenario
The environment:
- There is one C# Library project in both branches, called MyProject.
- There are two classes in each project, called MyClass and MyOtherClass.
- Branch A is the parent branch, and Branch B has been created from it.
The scenario:
- MyClass.cs is edited in Branch A and renamed to MyClassRenamed.cs.
- MyClass.cs is edited with a conflicting change in Branch B, but retains its name.
The outcome:
- Merging the changes produces one conflict.
- The conflict cannot be Auto Merged, and it only indicates issues with the content of the file, not the name change.
- Fixing the conflict leaves you with files named differently in both environments, despite what name the file has when resolving the conflict.
The correct scenario
Interestingly, the behaviour is different if the scenario is inversed, see below.
- MyClass.cs is edited with a conflicting change in Branch A, but retains its name.
- MyClass.cs is edited in Branch B and renamed to MyClassRenamed.cs.
The outcome:
- Merging produces TWO conflicts.
- One conflict is the project file, and the other being the file which has renamed.
- The conflict for the renamed file cannot be Auto Merged, but it notifies that the name has changed and asks for the new name for the merged file.
- You can then merge the changes for that file.
- You can then merge the changes for the project file.
- Fixing the conflict leaves you with files named differently in both environments, despite what name the file has when resolving the conflict.
- Everything works as expected, and the file is renamed in both environments and the changes kept in sync.
Conclusion
As far as I can see, the only solution is to avoid renaming files and to fix the issue manually after a merge, something I am hesitant to do if there is an automated way I can do this.
Let me a bit extend your scenario.
MyClass.cs is edited in Branch A and renamed to MyClassRenamed.cs.
MyClass.cs is edited with a conflicting change in Branch B, but retains its name.
One of these Branches had to be merged into Integration branch (let’s say Branch A)
At this moment of time, team working on Branch B decided to merge changes into Integration branch. As a good practice, before merging into Integration, they should pull down the changes from Integration and merge into branch B. Only after they do that and fix conflicts, they would merge branch B into Integration.
Next time Branch A to be merge, they should also follow good practice.
The above practice should resolve the issue of file names being different in the different Branches.