test: Test that an unconfirmed not-in-mempool chain is rebroadcast

test/functional/wallet_resendwallettransactions.py

@@ -11,8 +11,10 @@
 )
 from test_framework.p2p import P2PTxInvStore
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal
-
+from test_framework.util import (
+    assert_equal,
+    assert_raises_rpc_error,
+)
 
 class ResendWalletTransactionsTest(BitcoinTestFramework):
     def set_test_params(self):
@@ -27,7 +29,10 @@ def run_test(self):
         peer_first = node.add_p2p_connection(P2PTxInvStore())
 
         self.log.info("Create a new transaction and wait until it's broadcast")
-        txid = node.sendtoaddress(node.getnewaddress(), 1)
+        unspent = node.listunspent()
+        parent_utxo = unspent[0]
+        indep_utxo = unspent[1]
+        txid = node.send(outputs=[{node.getnewaddress(): 1}], options={"inputs": [parent_utxo]})["txid"]
 
         # Wallet rebroadcast is first scheduled 1 sec after startup (see
         # nNextResend in ResendWalletTransactions()). Tell scheduler to call
@@ -74,6 +79,41 @@ def run_test(self):
         node.setmocktime(now + 36 * 60 * 60 + 600)
         peer_second.wait_for_broadcast([txid])
 
+        self.log.info("Chain of unconfirmed not-in-mempool txs are rebroadcast")
+        # Ideally we would add a transaction that would spend the existing transaction and also be
+        # in mapWallet before it. However mapWallet is a std::unsorted_map which means that it is
+        # hard for us to externally construct such a transaction. So we will ignore that fact and
+        # rely on the fact that because there are only two items in mapWallet, 50% of the time the
+        # child will be placed before the parent in mapWallet. The incorrect behavior that this
+        # test tries to catch should thus fail intermittently at a rate of 50%.
+        send_res = node.send(outputs=[{node.getnewaddress(): 0.5}], options={"inputs": [{"txid":txid, "vout":0}], "add_to_wallet": False})
+        child_txid = send_res["txid"]
+        node.sendrawtransaction(send_res["hex"])
+        entry_time = node.getmempoolentry(child_txid)["time"]
+
+        block_time = entry_time + 6 * 60
+        node.setmocktime(block_time)
+        block = create_block(int(node.getbestblockhash(), 16), create_coinbase(node.getblockcount() + 1), block_time)
+        block.solve()
+        node.submitblock(block.serialize().hex())
+        node.syncwithvalidationinterfacequeue()
+
+        # Evict these txs from the mempool
+        evict_time = block_time + 60 * 60 * 336 + 5
+        node.setmocktime(evict_time)
+        indep_send = node.send(outputs=[{node.getnewaddress(): 1}], options={"inputs": [indep_utxo]})
+        node.syncwithvalidationinterfacequeue()
+        node.getmempoolentry(indep_send["txid"])
+        assert_raises_rpc_error(-5, "Transaction not in mempool", node.getmempoolentry, txid)
+        assert_raises_rpc_error(-5, "Transaction not in mempool", node.getmempoolentry, child_txid)
+
+        # Rebroadcast and check that parent and child are both in the mempool
+        with node.assert_debug_log(['ResendWalletTransactions: resubmit 2 unconfirmed transactions']):
+            node.setmocktime(evict_time + 36 * 60 * 60)
+            node.mockscheduler(1)
+        node.getmempoolentry(txid)
+        node.getmempoolentry(child_txid)
+
 
 if __name__ == '__main__':
     ResendWalletTransactionsTest().main()