DumpDir prints the contents of the directory to the testing logger.

DumpDirOnFailure prints the contents of the directory to the testing logger if the test has failed.

RequiresRoot skips tests that require root, unless the test.root flag has been set.

RequiresRootM is similar to RequiresRoot but intended to be called from *testing.M.

Unmount unmounts a given mountPoint and sets t.Error if it fails.