Merge bitcoin/bitcoin#29428: test: Assumeutxo: snapshots with less work should not be loaded

df6dc2a test: Assumeutxo: snapshots with less work should not be loaded (Hernan Marino)

Pull request description:

  This PR adds a test which checks that snapshots with less accumulated work than the node's active chain, should not be loaded and return with an error. Although in a different context of discussion the missing test was detect in a thread in bitcoin/bitcoin#29394 (see bitcoin/bitcoin#29394 (comment))

ACKs for top commit:
  maflcko:
    utACK df6dc2a
  kevkevinpal:
    utACK [df6dc2a](bitcoin/bitcoin@df6dc2a)
  achow101:
    ACK df6dc2a
  alfonsoromanz:
    Re ACK df6dc2a. Make is successful and the test passes.

Tree-SHA512: 07a394b4b288cc8ad3f66ed4e70dcda468db18113e9442eb7215cf491768432d55efaaa5b79d633094917e05475a30f0c5e4f64f8f2da293ba306891b4485560

Author: achow101

test/functional/feature_assumeutxo.py

@@ -196,6 +196,14 @@ def test_invalid_file_path(self):
         path = node.datadir_path / node.chain / "invalid" / "path"
         assert_raises_rpc_error(-8, "Couldn't open file {} for reading.".format(path), node.loadtxoutset, path)
 
+    def test_snapshot_with_less_work(self, dump_output_path):
+        self.log.info("Test bitcoind should fail when snapshot has less accumulated work than this node.")
+        node = self.nodes[0]
+        assert_equal(node.getblockcount(), FINAL_HEIGHT)
+        with node.assert_debug_log(expected_msgs=["[snapshot] activation failed - work does not exceed active chainstate"]):
+            assert_raises_rpc_error(-32603, "Unable to load UTXO snapshot", node.loadtxoutset, dump_output_path)
+        self.restart_node(0, extra_args=self.extra_args[0])
+
     def run_test(self):
         """
         Bring up two (disconnected) nodes, mine some new blocks on the first,
@@ -277,6 +285,7 @@ def run_test(self):
 
         assert_equal(n0.getblockchaininfo()["blocks"], FINAL_HEIGHT)
 
+        self.test_snapshot_with_less_work(dump_output['path'])
         self.test_invalid_mempool_state(dump_output['path'])
         self.test_invalid_snapshot_scenarios(dump_output['path'])
         self.test_invalid_chainstate_scenarios()