Loading .config files in NUnit

Last week I gave a presentation at Microsoft DevDays 2004 in Lisbon on Test-Driven Development. A day later I got this interesting question:

"(...) if I'm testing a DLL assembly that uses a .config file to read in data, when I run the tests, NUnit loads it's own .config file and all my tests fail. How can I solve this ?"

I also had this same problem a while back. There are two separate answers to this question as far as I could tell:

  1. If we're using the NUnit GUI than it's just a question to specify which .config file to load (Project -> Edit)
  2. If we're running NUnit from the console, copy the config file to the directory where the test assembly is located (tipically bin\Debug) and rename the config file to <test assembly>.config (ex: UniTests.dll.config)

This will cause NUnit to load the required .config file.