Visual Studio: Common problems with VSMDI files

Visual Studio provides solid support for unit testing. One of the features are VSMDI files – test meta data file. The file is not much readable but Visual Studio comes with easy to use GUI for managing tests (grouping them in test lists, filtering, etc.).

All in all, VSMDI files are really helpful but…

  1. After a while there are several VSMDI files (MySolutionName1.vsmdi, MySolutionName2.vsmdi, MySolutionName3.vsmdi, …) in your project although only one is in use (and therefore added to source control). This is a known bug discovered in Visual Studio 2005. More information can be found there.
  2. Painful merging. Merging can be smooth or really painful. It is the latter with VSMDI. Sorry, with VSMDI there’s no such thing like merging. If you discover someone else has changed and checked in VSMDI file (conflict), just replace your local changes with server version and repeat your changes.

    The reason for the mess here is each test is given ID which is a GUID which tends to change once in a while.

  3. Not runnable tests. This doesn’t happen too often but I’ve experienced it several times already. When you try to run some tests you are told they are not runnable because there are multiple tests with the same ID (again, IDs…) – see below. Of course you haven’t played with IDs…
    notrunnable 350x83 Visual Studio: Common problems with VSMDI files

    At least this is an easy one (but not when you see that for the first time). Just refresh the whole test list view – select List of Tests in Test List Editor window and click refresh.

Ok, so that’s my list. Any points to add here?

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