Removing .git dirs requires a bit more effort on windows.

dulwich/tests/compat/test_client.py

@@ -23,7 +23,6 @@ from io import BytesIO
 import copy
 import os
 import select
-import shutil
 import signal
 import subprocess
 import sys
@@ -63,6 +62,7 @@ from dulwich.tests import (
     )
 from dulwich.tests.utils import (
     skipIfPY3,
+    rmtree_ro,
     )
 from dulwich.tests.compat.utils import (
     CompatTestCase,
@@ -83,7 +83,7 @@ class DulwichClientTestBase(object):
         run_git_or_fail(['init', '--quiet', '--bare'], cwd=self.dest)
 
     def tearDown(self):
-        shutil.rmtree(self.gitroot)
+        rmtree_ro(self.gitroot)
 
     def assertDestEqualsSrc(self):
         src = repo.Repo(os.path.join(self.gitroot, 'server_new.export'))

dulwich/tests/compat/utils.py

@@ -20,10 +20,13 @@
 """Utilities for interacting with cgit."""
 
 import errno
+import functools
 import os
 import shutil
 import socket
+import stat
 import subprocess
+import sys
 import tempfile
 import time
 
@@ -230,5 +233,15 @@ class CompatTestCase(TestCase):
         :returns: An initialized Repo object that lives in a temporary directory.
         """
         path = import_repo_to_dir(name)
-        self.addCleanup(shutil.rmtree, path)
+        self.addCleanup(rmtree_ro, path)
         return Repo(path)
+
+
+if sys.platform == 'win32':
+    def remove_ro(action, name, exc):
+        os.chmod(name, stat.S_IWRITE)
+        os.remove(name)
+
+    rmtree_ro = functools.partial(shutil.rmtree, onerror=remove_ro)
+else:
+    rmtree_ro = shutil.rmtree