New Features in TFS 2008
Jeff walks you through the best of what's new in Team Foundation Server 2008, starting with the many helpful additions to Version Control.
- By Jeff Levinson
The list of new and enhanced features in Team Foundation Server (TFS) 2008
is quite extensive. I'll start diving into the details of these new features
in future columns. In the meantime, this column will focus on some of the new
features of Version Control, specifically, Annotate, Folder Diff, Destroy and
the Get Latest On Checkout feature (and for you SourceSafe fans, I'll also tell
you why you should be cautious when using it!).
Team System 2005, while a very stable system, was a version 1 release. Team
System 2008 adds more stability, more scalability and more (and better) tool
integration. It also incorporates a lot of requests from developers. The items
covered in this column fall into the tool integration and developer requests
After the initial 2005 release, Microsoft released a set of Power Tools for
TFS which included the Annotate feature. This allowed you to view a version
of a file and see all the changes that have been made to it so far. It also
noted who made the change and what changeset it was a part of.
When you installed the TFS Power Tools, this option was added to the IDE menu
or could be run from the command line, but it was relatively unknown. To use
this option, right-click a file in Source Control Explorer (or the History window)
and select Annotate.
As you can see in Figure
1, John created the file as part of changeset 14. Steve then made some changes,
and Lori made even more changes. You can get additional details on the changeset
by clicking the changeset number on the left. In addition, you can drill down
and annotate each version of the file -- very handy for figuring out who broke
what and when!
In TFS 2005, you could compare files for differences, but not the contents of
folders. TFS 2008 adds the ability to perform a folder diff. This makes it very
easy to see changes between different branches or labels at the file level.
2 shows that a comparison was done between two different server paths to
view the differences between the Production and Development branches of the
HelloWorld project. You can also perform a folder diff by comparing a server
path to a local path or two local paths.
Get Latest on Checkout
Finally, due to popular demand, TFS 2008 allows you to set a "Get Latest
on Checkout" option, which retrieves the latest version of a file when
you start editing it.
In 2005, when you started editing (or did a Check Out For Edit), it checked
out the version you currently had on your local machine. For example, if there
was a file called foo.cs that had four versions and you checked in version 3,
that was the version on your local machine. If another developer made changes
to that version and checked it in, then there was a version 4 in TFS.
Now, if you started editing version 3, TFS would check out version 3. When
you checked the file in, you'd get a conflict that you had to resolve. In Visual
SourceSafe, when you started editing version 3, it would automatically get version
4 and that's what you would be editing.
The Team System team has now added this feature to TFS 2008 (you have to set
this feature; it isn't on by default). But is this a good thing, and should
you use it?
The short answer is no. Here's the problem: Let's say that Developer A makes
changes to three files called A.cs, B.cs and C.cs and checks those files in.
Now, say Developer B makes changes to B.cs, C.cs and adds a new file called
D.cs. When Developer A next goes to edit B.cs, TFS is going to perform a Get
Latest and Checkout of just that file.
The problem is obvious: Developer B checked in files B, C and D together as
a single changeset and presumably made changes in such a way that these three
files have dependencies on one another. If Developer B is only editing the new
version of B.cs, then the code will never compile correctly and -- even worse
-- Developer A may change B.cs to make it build!
In general, my advice is to not use this feature but to get into the habit
of performing a Get Latest before you start working with code, and certainly
before you do a check in.
Jeff Levinson is the Application Lifecycle Management practice lead for Northwest Cadence specializing in process and methodology. He is the co-author of "Pro Visual Studio Team System with Database Professionals" (Apress 2007), the author of "Building Client/Server Applications with VB.NET" (Apress 2003) and has written numerous articles. He is an MCAD, MCSD, MCDBA, MCT and is a Team System MVP. He has a Masters in Software Engineering from Carnegie Mellon University and is a former Solutions Design and Integration Architect for The Boeing Company. You can reach him at Jeff.Levinson@nwcadence.com.