RSRP-288019: Resharper Testrunner running class without [TestFixture]

I included a ZIP with a sample.

Environment:

The issue is this:

we have a (non-abstract) test base class that defines the tests (methods marked with [Test] attribute) - this is modelled by the "NonAbstractBaseClass.cs" in my sample
that base class also has a virtual method which defines some operation (a calculation, basically)
the base class **IS NOT** marked with the [TestFixture] attribute - so as far as I understand NUnit, this is **NOT** a test class and it **SHOULD NOT** be executed
we have several descendant classes of this test base class that implement various versions of the calculation (but nothing else) - this is modelled by the "ActualTestFixture.cs" class in my sample
those descendants are marked with [TestFixture] - so those **ARE** test classes and ought to be executed when testing

The observed behavior I'm seeing (and have been seeing with Resharper 5.1 and this latest build):

even though the "NonAbstractBaseClass" clearly has **NO** [TestFixture] on it, Resharper's Testrunner insists on running the tests defined in that class, and those of course fail miserably since the calculation isn't implemented in that class

The EXPECTED behavior would be:

since the "NonAbstractBaseClass" clearly has **NO** [TestFixture] on it, Resharper's Testrunner **SHOULD NOT RUN IT** - to be in line with how NUnit on our build server behaves

I also included three screenshots in the "Screenshots" folder of the ZIP file:

NonAbstract_BaseClass_Tests_are_run.png: shows how Resharper Testrunner actually attempts to run the test in the base class
Abstract_BaseClass_Tests_are_NOT_run.png: shows how Resharper Testrunner rightfully doesn't run the test in the base class when it's abstract
NUnit Testrunner.png: shows how NUnit's graphical test runner handles the tests when using the non-abstract base class without the [TestFixture] attribute (a clear difference to how Resharper's testrunner mis-handles the same case)