Add back some tests for xray. (#2772)

test/runtest.py

@@ -1675,25 +1675,30 @@ class ResourcesTest(unittest.TestCase):
         ray.get(a1.test.remote())
 
     @unittest.skipIf(
-        os.environ.get("RAY_USE_XRAY") == "1",
-        "This test does not work with xray yet.")
+        os.environ.get("RAY_USE_XRAY") != "1",
+        "This test only works with xray.")
     def testZeroCPUs(self):
+        ray.init(num_cpus=0)
+
+        @ray.remote(num_cpus=0)
+        def f():
+            return 1
+
+        # The task should be able to execute.
+        ray.get(f.remote())
+
+    def testZeroCPUsActor(self):
         ray.worker._init(
             start_ray_local=True, num_local_schedulers=2, num_cpus=[0, 2])
 
         local_plasma = ray.worker.global_worker.plasma_client.store_socket_name
 
-        @ray.remote(num_cpus=0)
-        def f():
-            return ray.worker.global_worker.plasma_client.store_socket_name
-
         @ray.remote
         class Foo(object):
             def method(self):
                 return ray.worker.global_worker.plasma_client.store_socket_name
 
         # Make sure tasks and actors run on the remote local scheduler.
-        assert ray.get(f.remote()) != local_plasma
         a = Foo.remote()
         assert ray.get(a.method.remote()) != local_plasma