As discussed in VFS-500 the RamProviderTestCase fails with FileNotFoundException in setUp() if it is running after the PermissionTest of LocalProviderTestCase. The attached patch will make sure the test file with the limited permissions will be removed after the test run. It also makes sure to name the file a bit easier to correlate with the test. It also fixes some copy+paste errors in comments. It also moves the test functions together (moves the private helper functions to the end of the file).
I am not sure why not all tests fail and why the problem occurs more often with VFS-500 applied. Could be a sequence thing?