[SUREFIRE-2211] Fix UNC classpath elements

[robseidel]

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[michael-o]

Please fix the failing test

[michael-o]

I have force-pushed on purpose. You destroyed those changes. Please restore and fix the issue again.

[robseidel]

Sorry, I didn't see your changes. I applied this PR's changes to the current master branch (and removed another tab character in my changes, which was interfering with the build before). I hope everything fits now.

[michael-o]

Sorry, I didn't see your changes. I applied this PR's changes to the current master branch (and removed another tab character in my changes, which was interfering with the build before). I hope everything fits now.

Still not the commit message I have applied. 😁

[robseidel]

I've now restored the commit message.

[michael-o]

@robseidel Thanks! Can you have a look why the assumption fails?

[robseidel]

Yeah, I will have a look at it. I want to exclude this test in non Windows environments and thought assumption is the way to go, like at SurefireHelperTest shouldEscapeWindowsPath, but I'm probably missing something.

[robseidel]

Seems like PowerMockRunner does not work with assumptions (powermock/powermock#428). I'll have to find another way to skip the test in a non Windows environment.

[robseidel]

I found a solution for the assumption problem. It works in my environment (changed assumeTrue to assumeFalse), so hopefully the build does run now.
(https://youtrack.jetbrains.com/issue/IDEA-288919/JUnit-4-assumption-throwing-error-instead-of-ignoring-test-when-using-PowerMock-runner)