The tests are present at Test Explorer but run command has no effect.
Looking at Output windows, for Test outputs it shows many errors like this:
MSTestAdapter failed to discover tests in class 'UnitTests.Adhoc' of assembly 'some test.dll' because Method not found: 'System.String Microsoft.VisualStudio.TestTools.UnitTesting.TestMethodAttribute.get_DisplayName()'..
Found out that had some assembly conflict not signal by visual studio as usual on the references tree node.
Removing Microsoft.VisualStudio.TestPlatform.TestFramework reference and adding again did the trick.
Here de difference at the project file:
Before:
<Reference Include="Microsoft.VisualStudio.TestPlatform.TestFramework, Version=14.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
<HintPath>..\..\packages\MSTest.TestFramework.2.0.0\lib\net45\Microsoft.VisualStudio.TestPlatform.TestFramework.dll</HintPath>
</Reference>
<Reference Include="Microsoft.VisualStudio.TestPlatform.TestFramework.Extensions, Version=14.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
<HintPath>..\..\packages\MSTest.TestFramework.2.0.0\lib\net45\Microsoft.VisualStudio.TestPlatform.TestFramework.Extensions.dll</HintPath>
</Reference>
After:
<Reference Include="Microsoft.VisualStudio.QualityTools.UnitTestFramework, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL" />