Revert ensure_tx function to original

nomenklatura/db.py

@@ -38,16 +38,12 @@ def get_statement_table() -> Table:
 
 @contextmanager
 def ensure_tx(conn: Connish = None) -> Generator[Connection, None, None]:
-    try:
-        if conn is not None:
-            yield conn
-        else:
-            engine = get_engine()
-            with engine.begin() as conn:
-                yield conn
-    finally:
-        if conn is not None:
-            conn.commit()
+    if conn is not None:
+        yield conn
+        return
+    engine = get_engine()
+    with engine.begin() as conn:
+        yield conn
 
 
 @cache

nomenklatura/store/sql.py

@@ -106,6 +106,7 @@ def flush(self) -> None:
             )
             with ensure_tx(self.store.engine.connect()) as conn:
                 conn.execute(stmt)
+                conn.commit()
         self.batch = set()
         self.batch_size = 0
 
@@ -129,6 +130,7 @@ def pop(self, entity_id: str) -> List[Statement]:
         statements: List[Statement] = list(self.store._iterate_stmts(q))
         with ensure_tx(self.store.engine.connect()) as conn:
             conn.execute(q_delete)
+            conn.commit()
         return statements