refactor: add Store.to_dict() and use it in connection + tests

Address review feedback:
- Add to_dict() method on Store for WebSocket request serialization
- Use store.to_dict() in Connection.__execute_sql instead of inline dict
- Replace duplicated _serialize_store() helper in tests with to_dict()
- Remove test_options_dict_is_mutable to avoid enshrining mutability

Author: james-willis

tests/test_store_options.py

@@ -35,12 +35,6 @@ def test_options_defensively_copied(self):
         original["delimiter"] = "|"
         assert "delimiter" not in store.options
 
-    def test_options_dict_is_mutable(self):
-        """Store is not frozen, so options dict can be mutated after construction."""
-        store = Store(format=StorageFormat.CSV, options={"header": "false"})
-        store.options["delimiter"] = "|"
-        assert store.options == {"header": "false", "delimiter": "|"}
-
 
 class TestStoreForDownloadWithOptions:
     """Tests for Store.for_download() with options parameter."""
@@ -69,22 +63,11 @@ def test_for_download_empty_options_normalized(self):
 
 
 class TestStoreSerializationWithOptions:
-    """Tests for store dict serialization matching connection.py's format."""
-
-    def _serialize_store(self, store: Store) -> dict:
-        """Replicate the serialization logic from Connection.__execute_sql."""
-        store_dict = {
-            "format": store.format.value,
-            "single": str(store.single).lower(),
-            "generate_presigned_url": str(store.generate_presigned_url).lower(),
-        }
-        if store.options:
-            store_dict["options"] = store.options
-        return store_dict
+    """Tests for Store.to_dict() serialization."""
 
     def test_serialize_without_options(self):
         store = Store.for_download(format=StorageFormat.GEOJSON)
-        d = self._serialize_store(store)
+        d = store.to_dict()
         assert d == {
             "format": "geojson",
             "single": "true",
@@ -97,7 +80,7 @@ def test_serialize_with_options(self):
             format=StorageFormat.CSV,
             options={"header": "false", "delimiter": "|"},
         )
-        d = self._serialize_store(store)
+        d = store.to_dict()
         assert d == {
             "format": "csv",
             "single": "true",
@@ -107,15 +90,15 @@ def test_serialize_with_options(self):
 
     def test_serialize_empty_options_omitted(self):
         store = Store(format=StorageFormat.PARQUET, options={})
-        d = self._serialize_store(store)
+        d = store.to_dict()
         assert "options" not in d
 
     def test_json_roundtrip_with_options(self):
         store = Store.for_download(
             format=StorageFormat.GEOJSON,
             options={"ignoreNullFields": "false"},
         )
-        d = self._serialize_store(store)
+        d = store.to_dict()
         payload = json.dumps(d)
         parsed = json.loads(payload)
         assert parsed["options"] == {"ignoreNullFields": "false"}
@@ -131,7 +114,7 @@ def test_full_request_shape(self):
             "execution_id": "test-id",
             "statement": "SELECT 1",
         }
-        store_dict = self._serialize_store(store)
+        store_dict = store.to_dict()
         request["store"] = store_dict
 
         assert request == {

wherobots/db/connection.py

@@ -279,14 +279,7 @@ def __execute_sql(
             request["enable_progress_events"] = True
 
         if store:
-            store_dict: dict[str, Any] = {
-                "format": store.format.value,
-                "single": str(store.single).lower(),
-                "generate_presigned_url": str(store.generate_presigned_url).lower(),
-            }
-            if store.options:
-                store_dict["options"] = store.options
-            request["store"] = store_dict
+            request["store"] = store.to_dict()
 
         self.__queries[execution_id] = Query(
             sql=sql,

wherobots/db/models.py

@@ -1,4 +1,5 @@
 from dataclasses import dataclass
+from typing import Any, Dict
 
 import pandas
 
@@ -76,6 +77,22 @@ def for_download(
             options=options,
         )
 
+    def to_dict(self) -> Dict[str, Any]:
+        """Serialize this Store to a dict for the WebSocket request.
+
+        Returns a dict suitable for inclusion as the ``"store"`` field in an
+        ``execute_sql`` request.  The ``options`` key is omitted when there
+        are no user-supplied options (backward compatible).
+        """
+        d: Dict[str, Any] = {
+            "format": self.format.value,
+            "single": str(self.single).lower(),
+            "generate_presigned_url": str(self.generate_presigned_url).lower(),
+        }
+        if self.options:
+            d["options"] = self.options
+        return d
+
 
 @dataclass
 class ExecutionResult: