FIX #526: Do not depend on test-sources

+ Move `HIDE_WINDOWS_KNOWN_ERRORS` flag from
`git.test.lib.helper-->git.util`;
  regular modules in main-sources folder also depend on that flag.
+ Use unittest.SkipTest instead of from non-standard `nose` lib.

Author: ankostis

Diff for: git/objects/submodule/base.py

@@ -39,7 +39,7 @@
 import logging
 import uuid
 from unittest.case import SkipTest
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.objects.base import IndexObject, Object
 
 __all__ = ["Submodule", "UpdateProgress"]

Diff for: git/test/lib/helper.py

@@ -31,11 +31,6 @@
 
 log = logging.getLogger('git.util')
 
-#: We need an easy way to see if Appveyor TCs start failing,
-#: so the errors marked with this var are considered "acknowledged" ones, awaiting remedy,
-#: till then, we wish to hide them.
-HIDE_WINDOWS_KNOWN_ERRORS = is_win and os.environ.get('HIDE_WINDOWS_KNOWN_ERRORS', True)
-
 #{ Routines
 
 
@@ -289,7 +284,7 @@ def remote_repo_creator(self):
                     You can also run the daemon on a different port by passing --port=<port>"
                     and setting the environment variable GIT_PYTHON_TEST_GIT_DAEMON_PORT to <port>
                     """ % temp_dir)
-                    from nose import SkipTest
+                    from unittest import SkipTest
                     raise SkipTest(msg) if is_win else AssertionError(msg)
                     # END make assertion
                 # END catch ls remote error

Diff for: git/test/performance/test_odb.py

@@ -6,7 +6,7 @@
 from unittest.case import skipIf
 
 from git.compat import PY3
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 
 from .lib import (
     TestBigRepoR

Diff for: git/test/test_base.py

@@ -128,7 +128,7 @@ def test_add_unicode(self, rw_repo):
         try:
             file_path.encode(sys.getfilesystemencoding())
         except UnicodeEncodeError:
-            from nose import SkipTest
+            from unittest import SkipTest
             raise SkipTest("Environment doesn't support unicode filenames")
 
         with open(file_path, "wb") as fp:

Diff for: git/test/test_index.py

@@ -43,7 +43,7 @@
     fixture,
     with_rw_repo
 )
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.test.lib import with_rw_directory
 from git.util import Actor, rmtree
 from gitdb.base import IStream

Diff for: git/test/test_repo.py

@@ -50,11 +50,11 @@
     assert_true,
     raises
 )
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.test.lib import with_rw_directory
 from git.util import join_path_native, rmtree, rmfile
 from gitdb.util import bin_to_hex
-from nose import SkipTest
+from unittest import SkipTest
 
 import functools as fnt
 import os.path as osp

Diff for: git/test/test_submodule.py

@@ -21,7 +21,7 @@
     with_rw_repo
 )
 from git.test.lib import with_rw_directory
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.util import to_native_path_linux, join_path_native
 
 

Diff for: git/test/test_tree.py

@@ -13,7 +13,7 @@
     Tree,
     Blob
 )
-from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
+from git.util import HIDE_WINDOWS_KNOWN_ERRORS
 from git.test.lib import TestBase
 
 

Diff for: git/util.py

@@ -17,7 +17,7 @@
 from functools import wraps
 
 from git.compat import is_win
-from gitdb.util import (    # NOQA
+from gitdb.util import (# NOQA
     make_sha,
     LockedFD,               # @UnusedImport
     file_contents_ro,       # @UnusedImport
@@ -44,7 +44,13 @@
 __all__ = ("stream_copy", "join_path", "to_native_path_windows", "to_native_path_linux",
            "join_path_native", "Stats", "IndexFileSHA1Writer", "Iterable", "IterableList",
            "BlockingLockFile", "LockFile", 'Actor', 'get_user_id', 'assure_directory_exists',
-           'RemoteProgress', 'CallableRemoteProgress', 'rmtree', 'unbare_repo')
+           'RemoteProgress', 'CallableRemoteProgress', 'rmtree', 'unbare_repo',
+           'HIDE_WINDOWS_KNOWN_ERRORS')
+
+#: We need an easy way to see if Appveyor TCs start failing,
+#: so the errors marked with this var are considered "acknowledged" ones, awaiting remedy,
+#: till then, we wish to hide them.
+HIDE_WINDOWS_KNOWN_ERRORS = is_win and os.environ.get('HIDE_WINDOWS_KNOWN_ERRORS', True)
 
 #{ Utility Methods
 
@@ -76,7 +82,6 @@ def onerror(func, path, exc_info):
         try:
             func(path)  # Will scream if still not possible to delete.
         except Exception as ex:
-            from git.test.lib.helper import HIDE_WINDOWS_KNOWN_ERRORS
             if HIDE_WINDOWS_KNOWN_ERRORS:
                 raise SkipTest("FIXME: fails with: PermissionError\n  %s", ex)
             else: