Baseless Merge with TFS 2010

When you would like to use Source Control Merge Wizard in Visual Studio (e.g.; by right clicking a branch folder then going to 'Branching and Merging' -> 'Merge') and you find that the intended target is not in the 'Target branch' selection that means the source does not have any relationship with the target. You can proof this from 'Branching and Merging' -> 'View Hierarchy' option. This is when we need to do baseless merge operation.

To perform this operation, we can use the merge command on TFS command line tool. The syntax is

Tf merge /baseless /recursive /version:[versionspec] [source path] [target path] 

- path can be physical folder or source control location.
- [versionspec] can be a changeset, range of (inclusive) changesets separated by '~' character, a label, a date or versions. If we don't specify /version then it will merge all changes.

Below are some examples:
- Merge all changes from branch to trunk

D:\My_Project>tf merge /baseless /recursive "$/My Project/branch/one" "$/My Project/trunk" 

- Merge all changesets up to changeset 1000

D:\My_Project>tf merge /baseless /recursive /version:1000 "$/My Project/branch/one" "$/My Project/trunk" 

- Merge only changeset 1000

D:\My_Project>tf merge /baseless /recursive /version:1000~1000 "$/My Project/branch/one" "$/My Project/trunk" 

- Merge changesets 1000 to 1010 inclusively

D:\My_Project>tf merge /baseless /recursive /version:1000~1010 "$/My Project/branch/one" "$/My Project/trunk" 

If it is happened that the merge causing a lot of checkouts of unmodified files then we can use TFS Power Tools to undo the checkouts.

D:\My Project\trunk>tfpt uu /r /noget *

'uu' - undo unchanged
'/r' - recursive
'/noget' - do the operation without getting latest


If this one is still not working and leaving a lot of unmodified files checked out, we have to do Undo Changes manually. This can be done through the Pending Changes view, right click on any file from the list then select 'Undo'. The Undo Pending Changes dialog will pop up. Check all the files then click 'Undo Changes' button. A confirmation dialog with the message "... has changed. Undo check-out and discard changes?' will be shown. Click 'No to All' button. Then all unmodified files will be reverted while the modified ones from the merge operation stay.


References:
Team Foundation Merge Command on MSDN
Command-Line Syntax (Version Control)