1 files changed, 53 insertions, 0 deletions
diff --git a/test/functional/mempool_spend_coinbase.py b/test/functional/mempool_spend_coinbase.py
new file mode 100755
index 0000000000..db0738c08a
--- /dev/null
+++ b/test/functional/mempool_spend_coinbase.py
@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+# Copyright (c) 2014-2017 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 *
+
+# 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()