Fix modin test (#4069)

python/ray/test/test_modin.py

@@ -2,10 +2,30 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 
-import ray  # noqa F401
+import pytest
+
+import ray
 
 
-def test_modin_import():
+@pytest.fixture
+def shutdown_only():
+    yield None
+    # The code after the yield will run as teardown code.
+    ray.shutdown()
+
+
+def test_modin_import_with_ray_init(shutdown_only):
+    ray.init(num_cpus=1)
+    import modin.pandas as pd
+    frame_data = [1, 2, 3, 4, 5, 6, 7, 8]
+    frame = pd.DataFrame(frame_data)
+    assert frame.sum().squeeze() == sum(frame_data)
+
+
+# The following can be activated once we have a modin release that
+# includes https://github.com/modin-project/modin/pull/472.
+@pytest.mark.skip(reason="needs #472 in modin")
+def test_modin_import(shutdown_only):
     import modin.pandas as pd
     frame_data = [1, 2, 3, 4, 5, 6, 7, 8]
     frame = pd.DataFrame(frame_data)