Can web.config transforms be chained?

Let's pretend that we have the following servers [dev, test, production] and that dev and test are very similar in configuration while production is quite different.

If I'm using web.config transforms that means I have to duplicate a lot of settings för Web.dev.config and Web.test.config. It would be very nice if I could use the same transform mechanism for my transforms so that test.config is based on dev.config.

I have thought of two possible approaches, i'm not sure any of them would work:

Try to get MSBuild to first transform dev.config and then run test.config against the result when we are running under test configuration
trying to get the transform mechanism to work for transformations files. I would somehow run test.config against dev.config and create a temporary file which I then use as as a transformation against Web.config.

Does anyone know if something like this is possible? And if so how would one go about to set it up?

Solution

The TransformXml is just an MSBUILD task that is invoked post compile. If you extend/mod your build you can have it run the transform task twice, or allow the normal run against your configurations, then provide a second file and use the task to perform that.

If you are familiar with msbuild, this is pretty simple. If not, reply/comment, and I'll try to provide examples later today.

But in the end, yes its possible, as I've had similar need on past projects.