test: add test for Taproot activation

test/functional/feature_elements_taproot_activation.py

@@ -0,0 +1,121 @@
+#!/usr/bin/env python3
+# Copyright (c) 2015-2020 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 Taproot soft fork activation for Elements
+
+Unlike Bitcoin, this (a) does not use Speedy Trial, and (b) does use
+a pair of new versionbits features which allows Taproot to have its
+own signalling period length (128 blocks on regtest) and activation
+threshold (100%).
+
+The primary purpose of this test is to confirm that this configuration
+works; the actual activation (e.g. how are Taproot-enabled transactions
+treated) is covered by other tests and by manual testing.
+
+There is an undocumented option `con_taproot_signal_start` which sets
+the block at which signalling starts; otherwise it is set to "always
+on" which means that signalling will not occur.
+"""
+
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import assert_equal
+
+class TaprootActivationTest(BitcoinTestFramework):
+    def set_test_params(self):
+        self.setup_clean_chain = True
+        self.num_nodes = 1
+
+    def skip_test_if_missing_module(self):
+        self.skip_if_no_wallet()
+
+    def test_activation(self, rpc, activation_height):
+        self.log.info("Testing activation at height %d" % activation_height)
+        activation_height = 128 * ((activation_height + 127) // 128)
+
+        assert_equal(rpc.getblockcount(), 0)
+
+        blocks = rpc.generatetoaddress(activation_height - 2, rpc.getnewaddress())
+        assert_equal(rpc.getblockcount(), activation_height - 2)
+
+        for n, block in enumerate(blocks):
+            decode = rpc.getblockheader(block)
+            if n < 143:
+                assert_equal (decode["versionHex"], "20000000")
+            elif n < 431:
+                # TESTDUMMY deployment: 144 blocks active, 144 blocks locked in
+                assert_equal (decode["versionHex"], "30000000")
+            else:
+                assert_equal (decode["versionHex"], "20000000")
+
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "defined")
+        # The 1023rd block does not signal, but changes the signalling state
+        # to "started" from "defined"
+        blocks = rpc.generatetoaddress(1, rpc.getnewaddress())
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "started")
+        assert_equal(rpc.getblockheader(blocks[0])["versionHex"], "20000000")
+
+        blocks = rpc.generatetoaddress(127, rpc.getnewaddress())
+        for n, block in enumerate(blocks):
+            decode = rpc.getblockheader(block)
+            assert_equal (decode["versionHex"], "20000004")
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "started")
+
+        # Fail to signal on the 128th block. Since the threshold for Taproot is
+        # 100% this will prevent activation. Note that our period is 128, not
+        # 144 (the default), as we have overridden the period for Taproot. On
+        # the main Liquid chain it is overridden to be one week of signalling.
+        block = rpc.getnewblockhex()
+        block = block[:1] + "0" + block[2:] # turn off Taproot signal
+        rpc.submitblock(block)
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "started")
+
+        # Run through another 128 blocks, without failing to signal
+        blocks = rpc.generatetoaddress(127, rpc.getnewaddress())
+        for n, block in enumerate(blocks):
+            decode = rpc.getblockheader(block)
+            assert_equal (decode["versionHex"], "20000004")
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "started")
+        # The 128th block then switches from "started" to "locked_in"
+        blocks = rpc.generatetoaddress(1, rpc.getnewaddress())
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "locked_in")
+        assert_equal(rpc.getblockheader(blocks[0])["versionHex"], "20000004")
+
+        # Run through another 128 blocks, which will go from "locked in" to "active" regardless of signalling
+        blocks = rpc.generatetoaddress(127, rpc.getnewaddress())
+        for n, block in enumerate(blocks):
+            decode = rpc.getblockheader(block)
+            assert_equal (decode["versionHex"], "20000004")
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "locked_in")
+        block = rpc.getnewblockhex()
+        block = block[:1] + "0" + block[2:] # turn off Taproot signal
+        rpc.submitblock(block)
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "active")
+
+        # After the state is "active", signallng stops by default.
+        blocks = rpc.generatetoaddress(1, self.nodes[0].getnewaddress())
+        assert_equal(rpc.getblockchaininfo()["softforks"]["taproot"]["bip9"]["status"], "active")
+        assert_equal(rpc.getblockheader(blocks[0])["versionHex"], "20000000")
+
+    def run_test(self):
+        # Test that regtest nodes without -con_taproot_signal_start never signal
+        self.log.info("Testing node not configured to activate taproot")
+        blocks = self.nodes[0].generatetoaddress(2500, self.nodes[0].getnewaddress())
+        assert_equal(self.nodes[0].getblockcount(), 2500)
+        for n, block in enumerate(blocks):
+            decode = self.nodes[0].getblockheader(block)
+            if n < 143:
+                assert_equal (decode["versionHex"], "20000000")
+            elif n < 431:
+                # TESTDUMMY deployment: 144 blocks active, 144 blocks locked in
+                assert_equal (decode["versionHex"], "30000000")
+            else:
+                assert_equal (decode["versionHex"], "20000000")
+
+        # Test activation starting from height 1000
+        self.restart_node(0, ["-con_taproot_signal_start=500"])
+        self.nodes[0].invalidateblock(self.nodes[0].getblockhash(1))
+        self.test_activation(self.nodes[0], 500)
+
+if __name__ == '__main__':
+    TaprootActivationTest().main()

test/functional/test_runner.py

@@ -216,6 +216,7 @@ BASE_SCRIPTS = [
     'mining_prioritisetransaction.py',
     'p2p_invalid_locator.py',
     'p2p_invalid_block.py',
+    'feature_elements_taproot_activation.py',
     # ELEMENTS: needs to be fixed
     #'p2p_invalid_messages.py',
     'p2p_invalid_tx.py',