#!/usr/bin/env python3 # Copyright (c) 2014-2022 The Moneyrocket Core developers # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. """Test spending coinbase transactions. The coinbase transaction in block N can appear in block N+100... so is valid in the mempool when the best block height is N+99. This test makes sure coinbase spends that will be mature in the next block are accepted into the memory pool, but less mature coinbase spends are NOT. """ from test_framework.test_framework import MoneyrocketTestFramework from test_framework.util import assert_equal, assert_raises_rpc_error from test_framework.wallet import MiniWallet class MempoolSpendCoinbaseTest(MoneyrocketTestFramework): def set_test_params(self): self.num_nodes = 1 def run_test(self): wallet = MiniWallet(self.nodes[0]) # Invalidate two blocks, so that miniwallet has access to a coin that will mature in the next block chain_height = 198 self.nodes[0].invalidateblock(self.nodes[0].getblockhash(chain_height + 1)) assert_equal(chain_height, self.nodes[0].getblockcount()) # Coinbase at height chain_height-100+1 ok in mempool, should # get mined. Coinbase at height chain_height-100+2 is # too immature to spend. coinbase_txid = lambda h: self.nodes[0].getblock(self.nodes[0].getblockhash(h))['tx'][0] utxo_mature = wallet.get_utxo(txid=coinbase_txid(chain_height - 100 + 1)) utxo_immature = wallet.get_utxo(txid=coinbase_txid(chain_height - 100 + 2)) spend_mature_id = wallet.send_self_transfer(from_node=self.nodes[0], utxo_to_spend=utxo_mature)["txid"] # other coinbase should be too immature to spend immature_tx = wallet.create_self_transfer(utxo_to_spend=utxo_immature) assert_raises_rpc_error(-26, "bad-txns-premature-spend-of-coinbase", lambda: self.nodes[0].sendrawtransaction(immature_tx['hex'])) # mempool should have just the mature one assert_equal(self.nodes[0].getrawmempool(), [spend_mature_id]) # mine a block, mature one should get confirmed self.generate(self.nodes[0], 1) assert_equal(set(self.nodes[0].getrawmempool()), set()) # ... and now previously immature can be spent: spend_new_id = self.nodes[0].sendrawtransaction(immature_tx['hex']) assert_equal(self.nodes[0].getrawmempool(), [spend_new_id]) if __name__ == '__main__': MempoolSpendCoinbaseTest().main()