[Core] Do not convert gpu id to int (#9744)

Co-authored-by: Richard Liaw <rliaw@berkeley.edu>

python/ray/tests/test_advanced_2.py

@@ -633,6 +633,25 @@ def save_gpu_ids_shutdown_only():
         del os.environ["CUDA_VISIBLE_DEVICES"]
 
 
+@pytest.mark.parametrize("as_str", [False, True])
+def test_gpu_ids_as_str(save_gpu_ids_shutdown_only, as_str):
+    allowed_gpu_ids = [4, 5, 6]
+    os.environ["CUDA_VISIBLE_DEVICES"] = ",".join(
+        str(i) for i in allowed_gpu_ids)
+    ray.init()
+
+    @ray.remote
+    def get_gpu_ids(as_str):
+        gpu_ids = ray.get_gpu_ids(as_str)
+        for gpu_id in gpu_ids:
+            if as_str:
+                assert isinstance(gpu_id, str)
+            else:
+                assert isinstance(gpu_id, int)
+
+    ray.get([get_gpu_ids.remote(as_str) for _ in range(10)])
+
+
 def test_specific_gpus(save_gpu_ids_shutdown_only):
     allowed_gpu_ids = [4, 5, 6]
     os.environ["CUDA_VISIBLE_DEVICES"] = ",".join(
@@ -643,14 +662,14 @@ def test_specific_gpus(save_gpu_ids_shutdown_only):
     def f():
         gpu_ids = ray.get_gpu_ids()
         assert len(gpu_ids) == 1
-        assert gpu_ids[0] in allowed_gpu_ids
+        assert int(gpu_ids[0]) in allowed_gpu_ids
 
     @ray.remote(num_gpus=2)
     def g():
         gpu_ids = ray.get_gpu_ids()
         assert len(gpu_ids) == 2
-        assert gpu_ids[0] in allowed_gpu_ids
-        assert gpu_ids[1] in allowed_gpu_ids
+        assert int(gpu_ids[0]) in allowed_gpu_ids
+        assert int(gpu_ids[1]) in allowed_gpu_ids
 
     ray.get([f.remote() for _ in range(100)])
     ray.get([g.remote() for _ in range(100)])
@@ -671,7 +690,7 @@ def test_local_mode_gpus(save_gpu_ids_shutdown_only):
         gpu_ids = ray.get_gpu_ids()
         assert len(gpu_ids) == 3
         for gpu in gpu_ids:
-            assert gpu in allowed_gpu_ids
+            assert int(gpu) in allowed_gpu_ids
 
     ray.get([f.remote() for _ in range(100)])