test: make notfound_on_unannounced more reliable

By using mocktime, we will always hit both the notfound
branch and the tx sent branch.
The previous version didn't achieve that due to timing
issues.

Co-authored-by: Martin Zumsande <[email protected]>

Author: davidgumberg

test/functional/p2p_leak_tx.py

@@ -102,27 +102,31 @@ def test_notfound_on_unannounced_tx(self):
         self.gen_node.disconnect_p2ps()
         inbound_peer = self.gen_node.add_p2p_connection(P2PNode())  # An "attacking" inbound peer
 
-        MAX_REPEATS = 100
-        self.log.info("Running test up to {} times.".format(MAX_REPEATS))
-        for i in range(MAX_REPEATS):
-            self.log.info('Run repeat {}'.format(i + 1))
-            wtxid = self.miniwallet.send_self_transfer(from_node=self.gen_node)["wtxid"]
-
-            want_tx = msg_getdata()
-            want_tx.inv.append(CInv(t=MSG_WTX, h=int(wtxid, 16)))
-            with p2p_lock:
-                inbound_peer.last_message.pop('notfound', None)
-            inbound_peer.send_and_ping(want_tx)
-            if inbound_peer.last_message.get('notfound'):
-                self.log.debug('tx {} was not yet announced to us.'.format(wtxid))
-                self.log.debug("node has responded with a notfound message. End test.")
-                assert_equal(inbound_peer.last_message['notfound'].vec[0].hash, int(wtxid, 16))
-                with p2p_lock:
-                    inbound_peer.last_message.pop('notfound')
-                break
-            else:
-                self.log.debug('tx {} was already announced to us. Try test again.'.format(wtxid))
-                assert int(wtxid, 16) in [inv.hash for inv in inbound_peer.last_message['inv'].inv]
+        # Set a mock time so that time does not pass, and gen_node never announces the transaction
+        self.gen_node.setmocktime(self.mocktime)
+        wtxid = int(self.miniwallet.send_self_transfer(from_node=self.gen_node)["wtxid"], 16)
+
+        want_tx = msg_getdata()
+        want_tx.inv.append(CInv(t=MSG_WTX, h=wtxid))
+        with p2p_lock:
+            inbound_peer.last_message.pop('notfound', None)
+        inbound_peer.send_and_ping(want_tx)
+        inbound_peer.wait_until(lambda: "notfound" in inbound_peer.last_message)
+        with p2p_lock:
+            assert_equal(inbound_peer.last_message.get("notfound").vec[0].hash, wtxid)
+            inbound_peer.last_message.pop('notfound')
+
+        # Move mocktime forward and wait for the announcement.
+        inbound_peer.last_message.pop('inv', None)
+        self.mocktime += 120
+        self.gen_node.setmocktime(self.mocktime)
+        inbound_peer.wait_for_inv([CInv(t=MSG_WTX, h=wtxid)], timeout=120)
+
+        # Send the getdata again, this time the node should send us a TX message.
+        inbound_peer.last_message.pop('tx', None)
+        inbound_peer.send_and_ping(want_tx)
+        self.wait_until(lambda: "tx" in inbound_peer.last_message)
+        assert_equal(wtxid, int(inbound_peer.last_message["tx"].tx.wtxid_hex, 16))
 
 
 if __name__ == '__main__':