Remove anti-pattern of using dataclass which does not allow effective…

… inheritance

noxfile.py

@@ -185,7 +185,6 @@ def unit(session):
 
 
 UNIT_TEST_STANDARD_DEPENDENCIES = [
-    "mock",
     "pytest",
 ]
 UNIT_TEST_DEPENDENCIES: List[str] = []

src/langchain_google_spanner/vector_store.py

@@ -87,11 +87,16 @@ def __post_init__(self):
             raise ValueError("vector_length must be >=1")
 
 
-@dataclass
 class SecondaryIndex:
-    index_name: str
-    columns: list[str]
-    storing_columns: Optional[list[str]] = None
+    def __init__(
+        self,
+        index_name: str,
+        columns: list[str],
+        storing_columns: Optional[list[str]] = None,
+    ):
+        self.index_name = index_name
+        self.columns = columns
+        self.storing_columns = storing_columns
 
     def __post_init__(self):
         # Check if column_name is None after initialization
@@ -102,17 +107,27 @@ def __post_init__(self):
             raise ValueError("Index Columns can't be None")
 
 
-@dataclass
 class VectorSearchIndex(SecondaryIndex):
     """
     The index for use with Approximate Nearest Neighbor (ANN) vector search.
     """
 
-    num_leaves: int
-    num_branches: int
-    tree_depth: int
-    index_type: DistanceStrategy
-    nullable_column: bool = False
+    def __init__(
+        self,
+        num_leaves: int,
+        num_branches: int,
+        tree_depth: int,
+        index_type: DistanceStrategy,
+        nullable_column: bool = False,
+        *args,
+        **kwargs,
+    ):
+        super().__init__(*args, **kwargs)
+        self.num_leaves = num_leaves
+        self.num_branches = num_branches
+        self.tree_depth = tree_depth
+        self.index_type = index_type
+        self.nullable_column = nullable_column
 
     def __post_init__(self):
         if self.index_name is None:
@@ -506,7 +521,7 @@ def _generate_create_table_sql(
                 )
             else:
                 embedding_column = TableColumn(
-                    embedding_column, "ARRAY<FLOAT64p>", is_null=True
+                    embedding_column, "ARRAY<FLOAT64>", is_null=True
                 )
 
         configs = [id_column, content_column, embedding_column]

tests/unit/test_vectore_store.py

@@ -85,7 +85,7 @@ def test_generate_create_table_sql(self):
             "id",
         )
         want = (
-            "CREATE TABLE users (\n  id STRING(36),\n  essays STRING(MAX),"
+            "CREATE TABLE IF NOT EXISTS users (\n  id STRING(36),\n  essays STRING(MAX),"
             + "\n  science_scores ARRAY<FLOAT64>\n) PRIMARY KEY(id)"
         )
         assert got == want