How to fix NUnit tests that aren't showing in Visual Studio Test Explorer
Every now and then a project I'm working on decides it's either going to not show some or (more annoyingly!) all of the NUnit unit tests that are present.
The most recent project I've seen this with had the following versions of NUnit and NUnit3TestAdapter, though I've seen it with others:
<package id="NUnit" version="3.10.1" targetFramework="net47" /> <package id="NUnit3TestAdapter" version="3.13.0" targetFramework="net47" />
The fix is simple: go to the C:\Users\[YOUR USERNAME HERE]\AppData\Local\Temp\VisualStudioTestExplorerExtensions folder and delete its contents. You will need to close Visual Studio to release locks on some files first.