fixing up decoder to handle name changes

tests/ast/decoder.py

@@ -160,28 +160,12 @@ def decode_dsl_map_expr(self, map_expr: Iterable) -> dict:
             python_map[key] = value
         return python_map
 
-    def decode_fn_name_expr(self, fn_name: proto.SpName) -> str:
-        """
-        Decode a function name expression to get the function name.
-
-        Parameters
-        ----------
-        fn_name : proto.FnName
-            The function name to decode.
-
-        Returns
-        -------
-        str
-            The decoded function name.
-        """
-        if hasattr(fn_name, "fn_name_flat"):
-            return fn_name.fn_name_flat.name
-        elif hasattr(fn_name, "fn_name_structured"):
-            return fn_name.fn_name_structured.name
-        else:
-            raise ValueError("Function name not found in proto.FnName")
+    def convert_name_to_list(self, name: any) -> List:
+        if isinstance(name, str):
+            return [name]
+        return [qualified_name for qualified_name in name]
 
-    def decode_table_name_expr(self, table_name: proto.SpName) -> str:
+    def decode_name_expr(self, table_name: proto.SpName) -> str:
         """
         Decode a table name expression to get the table name.
 
@@ -195,10 +179,10 @@ def decode_table_name_expr(self, table_name: proto.SpName) -> str:
         str
             The decoded table name.
         """
-        if hasattr(table_name, "sp_table_name_flat"):
-            return table_name.sp_table_name_flat.name
-        elif hasattr(table_name, "sp_table_name_structured"):
-            return table_name.sp_table_name_structured.name
+        if table_name.name.HasField("sp_name_flat"):
+            return table_name.name.sp_name_flat.name
+        elif table_name.name.HasField("sp_name_structured"):
+            return table_name.name.sp_name_structured.name
         else:
             raise ValueError("Table name not found in proto.SpTableName")
 
@@ -222,7 +206,7 @@ def decode_fn_ref_expr(self, fn_ref_expr: proto.FnRefExpr) -> str:
             # case "trait_fn_name_ref_expr":
             #     pass
             case "builtin_fn":
-                return self.decode_fn_name_expr(fn_ref_expr.builtin_fn.name)
+                return self.decode_name_expr(fn_ref_expr.builtin_fn.name)
             # case "call_table_function_expr":
             #     pass
             # case "indirect_table_fn_id_ref":
@@ -795,9 +779,9 @@ def decode_expr(self, expr: proto.Expr) -> Any:
 
             case "sp_column_string_substr":
                 col = self.decode_expr(expr.sp_column_string_substr.col)
-                len = self.decode_expr(expr.sp_column_string_substr.len)
+                length = self.decode_expr(expr.sp_column_string_substr.len)
                 pos = self.decode_expr(expr.sp_column_string_substr.pos)
-                return col.substr(pos, len)
+                return col.substr(pos, length)
 
             case "sp_column_string_ends_with":
                 col = self.decode_expr(expr.sp_column_string_ends_with.col)
@@ -1318,7 +1302,7 @@ def decode_expr(self, expr: proto.Expr) -> Any:
 
             case "sp_table":
                 assert expr.sp_table.HasField("name")
-                table_name = self.decode_table_name_expr(expr.sp_table.name)
+                table_name = self.decode_name_expr(expr.sp_table.name)
                 return self.session.table(table_name)
 
             case "udf":
@@ -1370,11 +1354,11 @@ def decode_expr(self, expr: proto.Expr) -> Any:
 
             case "sp_dataframe_create_or_replace_view":
                 df = self.decode_expr(expr.sp_dataframe_create_or_replace_view.df)
-                name = [
-                    qualified_name
-                    for qualified_name in expr.sp_dataframe_create_or_replace_view.name
-                ]
-
+                name = self.decode_name_expr(
+                    expr.sp_dataframe_create_or_replace_view.name
+                )
+                if not isinstance(name, str):
+                    name = self.convert_name_to_list(name)
                 statement_params = None
                 if hasattr(
                     expr.sp_dataframe_create_or_replace_view, "statement_params"
@@ -1406,10 +1390,10 @@ def decode_expr(self, expr: proto.Expr) -> Any:
 
             case "sp_dataframe_copy_into_table":
                 df = self.decode_expr(expr.sp_dataframe_copy_into_table.df)
-                name = [
-                    qualified_name
-                    for qualified_name in expr.sp_dataframe_copy_into_table.table_name
-                ]
+                name = self.decode_name_expr(
+                    expr.sp_dataframe_copy_into_table.table_name
+                )
+                name = self.convert_name_to_list(name)
                 files = [
                     file_name for file_name in expr.sp_dataframe_copy_into_table.files
                 ]
@@ -1482,10 +1466,11 @@ def decode_expr(self, expr: proto.Expr) -> Any:
                 df = self.decode_expr(
                     expr.sp_dataframe_create_or_replace_dynamic_table.df
                 )
-                name = [
-                    qualified_name_part
-                    for qualified_name_part in expr.sp_dataframe_create_or_replace_dynamic_table.name
-                ]
+                name = self.decode_name_expr(
+                    expr.sp_dataframe_create_or_replace_dynamic_table.name
+                )
+                if not isinstance(name, str):
+                    name = self.convert_name_to_list(name)
                 warehouse = expr.sp_dataframe_create_or_replace_dynamic_table.warehouse
                 lag = expr.sp_dataframe_create_or_replace_dynamic_table.lag
                 comment = (