Add support for more generic Hashable args

Signed-off-by: Alexey Kudinkin <ak@anyscale.com>

python/ray/data/_internal/remote_fn.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, List
+from typing import Any, Dict, Hashable, List
 
 import ray
 
@@ -50,7 +50,7 @@ def _make_hashable(obj):
     elif isinstance(obj, Dict):
         converted = [(_make_hashable(k), _make_hashable(v)) for k, v in obj.items()]
         return tuple(sorted(converted, key=lambda t: t[0]))
-    elif isinstance(obj, (bool, int, float, str, bytes, type(None))):
+    elif isinstance(obj, Hashable):
         return obj
     else:
         raise ValueError(f"Type {type(obj)} is not hashable")

python/ray/data/tests/test_util.py

@@ -2,6 +2,7 @@
 
 import numpy as np
 import pytest
+from typing_extensions import Hashable
 
 import ray
 from ray.data._internal.datasource.parquet_datasource import ParquetDatasource
@@ -45,6 +46,7 @@ def test_make_hashable():
         },
         "list": list(range(10)),
         "tuple": tuple(range(3)),
+        "type": Hashable,
     }
 
     hashable_args = _make_hashable(valid_args)
@@ -57,6 +59,7 @@ def test_make_hashable():
             ("list", (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)),
             ("str", "foo"),
             ("tuple", (0, 1, 2)),
+            ("type", Hashable),
         )
     )
 
@@ -70,22 +73,6 @@ def test_make_hashable():
         str(exc_info.value) == "'<' not supported between instances of 'str' and 'int'"
     )
 
-    # Invalid case # 2: can't use anything but dict, list, tuple or primitive types
-    class Foo:
-        bar: 0
-
-    invalid_args = {
-        0: Foo(),
-    }
-
-    with pytest.raises(ValueError) as exc_info:
-        _make_hashable(invalid_args)
-
-    assert (
-        str(exc_info.value)
-        == "Type <class 'test_util.test_make_hashable.<locals>.Foo'> is not hashable"
-    )
-
 
 def test_check_pyarrow_version_bounds(unsupported_pyarrow_version):
     # Test that pyarrow versions outside of the defined bounds cause an ImportError to