raise if MemoryStore is pickled

src/zarr/store/memory.py

@@ -37,16 +37,10 @@ def __eq__(self, other: object) -> bool:
         )
 
     def __setstate__(self, state: tuple[MutableMapping[str, Buffer], OpenMode]) -> None:
-        # warnings.warn(
-        #     f"unpickling {type(self)} may produce unexpected behavior and should only be used for testing and/or debugging"
-        # )
-        self._store_dict, self._mode = state
+        raise NotImplementedError(f"{type(self)} cannot be pickled")
 
     def __getstate__(self) -> tuple[MutableMapping[str, Buffer], OpenMode]:
-        # warnings.warn(
-        #     f"pickling {type(self)} may produce unexpected behavior and should only be used for testing and/or debugging"
-        # )
-        return self._store_dict, self._mode
+        raise NotImplementedError(f"{type(self)} cannot be pickled")
 
     async def get(
         self,

tests/v3/test_array.py

@@ -39,7 +39,7 @@ def test_array_name_properties_with_group(
     assert spam.basename == "spam"
 
 
-@pytest.mark.parametrize("store", ("memory", "local"), indirect=["store"])
+@pytest.mark.parametrize("store", ("local",), indirect=["store"])
 @pytest.mark.parametrize("zarr_format", (2, 3))
 async def test_serizalizable_async_array(
     store: LocalStore | MemoryStore, zarr_format: ZarrFormat
@@ -57,7 +57,7 @@ async def test_serizalizable_async_array(
     # TODO: uncomment the parts of this test that will be impacted by the config/prototype changes in flight
 
 
-@pytest.mark.parametrize("store", ("memory", "local"), indirect=["store"])
+@pytest.mark.parametrize("store", ("local",), indirect=["store"])
 @pytest.mark.parametrize("zarr_format", (2, 3))
 def test_serizalizable_sync_array(store: LocalStore | MemoryStore, zarr_format: ZarrFormat) -> None:
     expected = Array.create(

tests/v3/test_group.py

@@ -394,7 +394,7 @@ def test_group_name_properties(store: LocalStore | MemoryStore, zarr_format: Zar
     assert bar.basename == "bar"
 
 
-@pytest.mark.parametrize("store", ("memory", "local"), indirect=["store"])
+@pytest.mark.parametrize("store", ("local",), indirect=["store"])
 @pytest.mark.parametrize("zarr_format", (2, 3))
 async def test_serizalizable_async_group(
     store: LocalStore | MemoryStore, zarr_format: ZarrFormat
@@ -407,7 +407,7 @@ async def test_serizalizable_async_group(
     assert actual == expected
 
 
-@pytest.mark.parametrize("store", ("memory", "local"), indirect=["store"])
+@pytest.mark.parametrize("store", ("local",), indirect=["store"])
 @pytest.mark.parametrize("zarr_format", (2, 3))
 def test_serizalizable_sync_group(store: LocalStore | MemoryStore, zarr_format: ZarrFormat) -> None:
     expected = Group.create(store=store, attributes={"foo": 999}, zarr_format=zarr_format)

tests/v3/test_store/test_memory.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import pickle
+
 import pytest
 
 from zarr.buffer import Buffer
@@ -38,3 +40,13 @@ def test_store_supports_partial_writes(self, store: MemoryStore) -> None:
 
     def test_list_prefix(self, store: MemoryStore) -> None:
         assert True
+
+    def test_serizalizable_store(self, store: MemoryStore) -> None:
+        with pytest.raises(NotImplementedError):
+            store.__getstate__()
+
+        with pytest.raises(NotImplementedError):
+            store.__setstate__({})
+
+        with pytest.raises(NotImplementedError):
+            pickle.dumps(store)