In TFS 2010, branching and merging have been greatly improved with support for branch visualization and tracking of changesets and work items across branches. A simple example of this looks like this:

Here we track Work Item nr 3 which was originally resovled in the Test branch (with changeset 35). We can also see that the work item has been merged into the Production branch (as changeset 37), back to Main (62) and finally to FeatureC (140).
If we switch to the Timeline view, we get a nice view of the order of these merges, together with the dates.
Unfortunately, this does not solve one of the bigger problems when it comes to branches and work items. When you merge your changes into another branch, you must remember to asociated the corresponding work item again, otherwise that information is lost and the work item will not show up in the build report from the builds running off the target branches. A typical example is that we have 3 bugs in the Test branch, and we perform (at least) 3 changesets and each changeset is associated to the corresponding work item. When it is time to merge the bug fixes to the Production branch, we must manually associated the merge with the work item again. If we peform one merge operation that brings all changes from Test to Main, we must associate all 3 work items. There is really no support for “merging” work items across branches in TFS, only changesets can be merged.
What you really want is to have the tool automatically assign the work items that were associated with the changesets that you are merging. One way to implement this is with a checkin policy, which we have done at our company. The reason for choosing a checkin policy as the tool of choice is because it is executed on the client at the time of the checkin, and we can display the work items to the developers before they check in.
So, how does it work? Lets look at an example:
In my development branch, I have 3 bugs (Bug1, Bug2 and Bug3) that I need to fix. I fix each one in a changeset that gets checked in and associated with the corresponding work item. Then it is time to merge the fixes to the Main branch (trunk).
I perform a merge by just using the normal Merge operation from source control. This leaves me with the following pending merge:

Now, I would normally go to the Work Items tab and link to the work items that I know were resolved by the changes that I am currently merging. But now I don’t need to do this but instead I just click on the Check In button. This will evaluate all checkin policies, and one of them is the Merge Work Items policy that pops up the following dialog:
![clip_image002[5] clip_image002[5]](http://geekswithblogs.net/images/geekswithblogs_net/jakob/Windows-Live-Writer/Merging-Work-Items-in-TFS-2010_12A4F/clip_image002%5B5%5D_thumb.jpg)
This dialog shows me a list of the work items that were associated with the changesets that I am currently merging in. The checkin policy uses the TFS Version Control API to locate the merge sources of each pending merge item and basically shows the union of these work items (several changesets can be associated with the same work item). If I check in now, the changeset will automatically be associated with these 3 work items! The beauty of this comes when running the builds off the Main branch, the build summary show me that these 3 work items have been resolved in this build:

In another post I will show the interesteing parts of the implementation