#!/usr/bin/env python3 # Copyright (c) 2014-2016 The Bitcoin 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 BitcoinTestFramework from test_framework.util import assert_equal, assert_raises_rpc_error, create_tx # Create one-input, one-output, no-fee transaction: class MempoolSpendCoinbaseTest(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 self.extra_args = [["-checkmempool"]] def run_test(self): chain_height = self.nodes[0].getblockcount() assert_equal(chain_height, 200) node0_address = self.nodes[0].getnewaddress() # Coinbase at height chain_height-100+1 ok in mempool, should # get mined. Coinbase at height chain_height-100+2 is # is too immature to spend. b = [self.nodes[0].getblockhash(n) for n in range(101, 103)] coinbase_txids = [self.nodes[0].getblock(h)['tx'][0] for h in b] spends_raw = [create_tx(self.nodes[0], txid, node0_address, 49.99) for txid in coinbase_txids] spend_101_id = self.nodes[0].sendrawtransaction(spends_raw[0]) # coinbase at height 102 should be too immature to spend assert_raises_rpc_error(-26, "bad-txns-premature-spend-of-coinbase", self.nodes[0].sendrawtransaction, spends_raw[1]) # mempool should have just spend_101: assert_equal(self.nodes[0].getrawmempool(), [spend_101_id]) # mine a block, spend_101 should get confirmed self.nodes[0].generate(1) assert_equal(set(self.nodes[0].getrawmempool()), set()) # ... and now height 102 can be spent: spend_102_id = self.nodes[0].sendrawtransaction(spends_raw[1]) assert_equal(self.nodes[0].getrawmempool(), [spend_102_id]) if __name__ == '__main__': MempoolSpendCoinbaseTest().main()