C# DeploymentItem fails to copy file for MSTest unit test

I'm having trouble getting an XSL file to be copied to the same directory as t开发者_StackOverflowhe test assembly when I use the DeploymentItem attribute on an MSTest unit test. I followed the chosen answer for this question and the file I need copied has its "Copy to Output Directory" set to "Copy Always". When I check my ProjectDir\bin directory (the Target directory), the file I want copied is indeed there, alongside the DLLs and PDBs.

I have a couple unit tests with the following setup:

private const string DLL = "Service.dll";
private const string XSL_PATH = "transform.xsl";

[TestInitialize]
public void InitializeTest()
{
    Assert.IsTrue(File.Exists(DLL)); // passes
}

[TestMethod]
[DeploymentItem(DLL)]
[DeploymentItem(XSL_PATH)]
public void XmlToResultsTest()
{
    Assert.IsTrue(File.Exists(XSL_PATH)); // fails
}

The XSL test fails because when I check MSTest's TestResults\particularTestRun\Out directory, I see the DLLs and the PDBs, but my XSL file is not there. What I want to know is why the XSL file does not get copied alongside the DLLs and PDBs even when I explicitly tell Visual Studio to copy it there via DeploymentItem?

Thanks to Marc Gravell's answer to a related question of mine, I tried updating my MSTest .testrunconfig file so that my XSL file is included in the 'Deployment' section. This lets my unit tests pass, but I'm still perturbed that I had to do this--shouldn't the combination of DeploymentItem and marking the file's properties in my project to copy to the output directory be sufficient?

Allegedly VS2008 deployment items silently fail unless the output directory is a literal string. Hmmm ^_^

I had the same problem even though I was using a literal string in the deployment item. I even tried adding the file to the 'Deployment' section of the test settings which didn't work either. It turned out that the problem was related to the testing platform.

I have a 64 bit machine and both the project I was testing and the unit test project's platform target were 'Any CPU'.

I found that the deployment item was only copied if I selected 'Run tests in a 64 bit process on 64 bit machine".

We had a similar situation at work where the DeploymentItem attribute was not working as expected. We were also using 64 bit machines, with project platform set at "Any CPU". As a workaround, we included the file required by the unit test as a link from the unit test project and set its "Copy to Output Directory" to "Copy Always".