normans review addressed

Author: konstntokas

test/core/store/test_store.py

@@ -7,7 +7,13 @@
 import pytest
 from fsspec.registry import register_implementation
 
-from xcube.core.store import DataStoreError, list_data_store_ids, new_data_store
+from xcube.core.store import (
+    DataStoreError,
+    PreloadedDataStore,
+    list_data_store_ids,
+    new_data_store,
+)
+from xcube.core.store.preload import NullPreloadHandle
 
 
 class ListDataStoreTest(unittest.TestCase):
@@ -84,6 +90,12 @@ def test_has_data(self, mock_filesystem):
         self.assertEqual(mock_http_fs.exists.call_count, 3)
         self.assertFalse(res)
 
+    def test_preload_data(self):
+        store = new_data_store("file")
+        store_test = store.preload_data()
+        self.assertTrue(hasattr(store_test, "preload_handle"))
+        self.assertIsInstance(store_test.preload_handle, NullPreloadHandle)
+
 
 def test_fsspec_instantiation_error():
     error_string = "deliberate instantiation error for testing"

xcube/core/store/store.py

@@ -487,7 +487,7 @@ def preload_data(
         self,
         *data_ids: str,
         **preload_params: Any,
-    ) -> "PreloadDataStore":
+    ) -> "PreloadedDataStore":
         """Preload the given data items for faster access.
 
         Warning: This is an experimental and potentially unstable API
@@ -704,4 +704,3 @@ def preload_handle(self) -> PreloadHandle:
         Implementors of this interface may use a `ExecutorPreloadHandle` or consider
         returning a `NullPreloadHandle` if the progress is not observable.
         """
-        pass