Current Working Directory Warning Issues

[rallytime]

The changes made in PR #93 are causing two test classes in a full jenkins test run to display the WARNING message that the pull request added about the misbehaving test/changing working directory.

However, it became apparent that this message displays at the beginning of every test run - which ever test class was the first class to run, then the WARNING will be triggered for the class.

I made the following edits to salttesting.unit.py to display what the current working directory is at various points of the tearDown process:

diff --git a/salttesting/unit.py b/salttesting/unit.py
index f082cfe..74b5db4 100644
--- a/salttesting/unit.py
+++ b/salttesting/unit.py
@@ -104,11 +104,17 @@ class TestCase(_TestCase):

         This hard-resets the environment between test classes
         '''
+        print('cls._cwd() = {0}'.format(cls._cwd))
+        print('os.get_cwd() = {0}'.format(os.getcwd()))
         # Compare where we are now compared to where we were when we began this family of tests
         if not cls._cwd == os.getcwd():
             os.chdir(cls._cwd)
             print('\nWARNING: A misbehaving test has modified the working directory!\nThe test suite has reset the working direct
                     'on tearDown() to {0}\n'.format(cls._cwd))
+        print('after warning')
+        print('os.get_cwd() = {0}'.format(os.getcwd()))
         super(TestCase, cls).tearDownClass()

Then, I ran a simple unit test like so: python2 runtests.py -n unit.spm_test which printed the following results:

.cls._cwd() = /root/SaltStack/salt/tests
os.get_cwd() = /root/SaltStack/salt

WARNING: A misbehaving test has modified the working directory!
The test suite has reset the working directory on tearDown() to /root/SaltStack/salt/tests

after warning
os.get_cwd() = /root/SaltStack/salt/tests
.cls._cwd() = /root/SaltStack/salt/tests
os.get_cwd() = /root/SaltStack/salt/tests
after warning
os.get_cwd() = /root/SaltStack/salt/tests

You can see that the call to os.getcwd() on this line of the change has a different working directory than what is present for the initial os.getcwd() call at the top of the TestCase class definition.

NOTE: We run an os.getcwd() call right at the beginning of the test run when we print some information about the test logger and the test PID, etc, which looks like this:

 * Transplanting configuration files to '/tmp/salt-tests-tmpdir/config'
 * Current Directory: /root/SaltStack/salt
 * Test suite is running under PID 32730
 * Logging tests on /tmp/salt-runtests.log

See that the Current Directory matches the os.getcwd() call in the overridden tearDown class.

I haven't been able to track down why this call to os.getcwd() is returning a different directory than one with the /tests extension.

@cachedout What do you think about this assessment?

This issue replaces saltstack/salt#36415 and saltstack/salt#36416