Why does visual studio 2012 not find my tests?

Question

I had same symptoms, but under different circumstances.

I had to add one additional step to Peter Lamberg's solution — Clean your solution/project.

My unittest project targets x64. When I created the project it was originally targeting x86.

After switching to x64 all my unit tests disappeared.

I had to go to the Test Menu -> Test Setting -Default Processor Architecture -> x64.

They still didn't show up.

Did a build.

Still didn't show up.

Finally did a Clean

Then they showed up.

I find Clean Solution and Clean to be quite useful at getting the solutions to play ball when setting have changed. Sometimes I have to go to the extreme and delete the obj and bin directories and do a rebuild.

Please add the keyword public to your class definition. Your test class is currently not visible outside its own assembly.

namespace tests {
    [TestClass]
    public class SimpleTest {
        [TestMethod]
        public void Test() {
            Assert.AreEqual("a","a", "same");
        }
    }
}

This sometimes works.

Check that the processor architecture under Test menu matches the one you use to build the solution.

Test -> Test Settings -> Default Processor Architecture -> x86 / x64

As mentioned in other posts, make sure you have the Test Explorer window open. Test -> Windows -> Test Explorer

Then rebuilding the project with the tests should make the tests appear in Test Explorer.

Edit: As Ourjamie pointed out below, doing a clean build may also help. In addition to that, here is one more thing I encountered:

The "Build" checkbox was unticked in Configuration Manager for a new test project I had created under the solution.

Go to Build -> Configuration Manager. Make sure your test project has build checkbox checked for all solution configurations and solution platforms.

I have Visual Studio 2012 and i couldn't see the Tests in Test Explorer,

So I installed the following: NUnit Test Adapter

That fixed the issue for me !

In my recent experience all of the above did not work. My test method

public async void ListCaseReplace() { ... }

was not showing up but compiling fine. When I removed the async keyword the test the showed up in the Test Explorer. This is bacause async void is a 'fire-and-forget' method. Make the method async Task and you will get your test back!

In addition, not having the Test project's configuration set to "Build" will also prevent tests from showing up. Configuration Manager > Check your Test to build.

Since the project is on a shared drive as the original poster have indicated. VS.NET needs to trust network location before it will load and run your test assemblies. Have a read of this blog post.

To allow VS.NET to load things of a network share one needs to add them (shares) to trusted locations. To add a location to a full trust list run (obviously amend as required for you environment):

 caspol -m -ag 1.2 -url file:///H:/* FullTrust

To verify or list existing trusted locations run:

 caspol -lg