diff --git a/ci_watson/plugin.py b/ci_watson/plugin.py
index 2e7829a..286ecb4 100644
--- a/ci_watson/plugin.py
+++ b/ci_watson/plugin.py
@@ -67,12 +67,12 @@ def pytest_runtest_setup(item):
 
 
 @pytest.fixture(scope='function')
-def _jail(tmpdir):
+def _jail(tmp_path):
     """Perform test in a pristine temporary working directory."""
     old_dir = os.getcwd()
-    os.chdir(tmpdir.strpath)
+    os.chdir(tmp_path)
     try:
-        yield tmpdir.strpath
+        yield str(tmp_path)
     finally:
         os.chdir(old_dir)
 
diff --git a/setup.cfg b/setup.cfg
index 25691c3..49c9736 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -59,3 +59,4 @@ junit_family = xunit2
 filterwarnings =
     error
     ignore:numpy.ndarray size changed:RuntimeWarning
+addopts = "-p no:legacypth"