Prevent assertion error on send_operations with errors

Signed-off-by: Jean-François <[email protected]>

massa_test_framework/node.py

@@ -6,7 +6,7 @@
 import time
 from urllib.parse import urlparse
 
-from typing import List, Dict, Optional, Callable
+from typing import List, Dict, Optional, Callable, Union
 
 import betterproto
 from grpclib.client import Channel
@@ -36,6 +36,7 @@
 import requests
 import tomlkit
 
+
 class Node:
     def __init__(self, server: Server, compile_unit: CompileUnit):
         """Init a Node (e.g. a Massa Node) object
@@ -280,7 +281,6 @@ def edit_config(self):
         # print("is fp closed:", fp.closed)
         # print("end of edit_config")
 
-
     @contextmanager
     def edit_json(self, json_filepath: Path, mode: str = "r+", default_json=None):
         fp = self.server.open(json_filepath, mode)
@@ -376,17 +376,27 @@ def add_staking_secret_keys(self, secret_keys: List[str]) -> None:
         res = self.priv_api2.add_staking_secret_keys(secret_keys)
         return res
 
-    def send_operations(self, operations: List[bytes]) -> List[str]:
+    def send_operations(
+        self, operations: List[bytes]
+    ) -> Union[List[str], Dict[str, str]]:
         """Send operations (like coin transfer)
 
         Send serialized operations using jsonrpc api
 
         Args:
             operations: a list of serialized operations
         Returns:
-            a list of operation id
+            on success: a list of operation id
+            on error: a dict with key "error" and value the error message
         """
         res = self.pub_api2.send_operations(operations)
+
+        # check if there is an error
+        err = res.get("error", None)
+        if err is not None:
+            msg = str(err.get("message", "Unknown error"))
+            return {"error": msg}
+
         return res["result"]
 
     def node_peers_whitelist(self):