From 8d0c03caff5879edb0c038d33602fc3721109f32 Mon Sep 17 00:00:00 2001
From: SomberNight <somber.night@protonmail.com>
Date: Sat, 27 Jun 2020 16:32:46 +0200
Subject: [PATCH] synchronizer: enforce that unconfirmed txs must have fee
 information

related: #6289
---
 electrum/synchronizer.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/electrum/synchronizer.py b/electrum/synchronizer.py
index e922ebc3e..86018c798 100644
--- a/electrum/synchronizer.py
+++ b/electrum/synchronizer.py
@@ -174,6 +174,9 @@ class Synchronizer(SynchronizerBase):
         hashes = set(map(lambda item: item['tx_hash'], result))
         hist = list(map(lambda item: (item['tx_hash'], item['height']), result))
         # tx_fees
+        for item in result:
+            if item['height'] in (-1, 0) and 'fee' not in item:
+                raise Exception("server response to get_history contains unconfirmed tx without fee")
         tx_fees = [(item['tx_hash'], item.get('fee')) for item in result]
         tx_fees = dict(filter(lambda x:x[1] is not None, tx_fees))
         # Check that txids are unique