1 files changed, 105 insertions, 0 deletions
diff --git a/test/functional/test_framework/blocktools.py b/test/functional/test_framework/blocktools.py
new file mode 100644
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+++ b/test/functional/test_framework/blocktools.py
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+#!/usr/bin/env python3
+# Copyright (c) 2015-2016 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Utilities for manipulating blocks and transactions."""
+
+from .mininode import *
+from .script import CScript, OP_TRUE, OP_CHECKSIG, OP_RETURN
+
+# Create a block (with regtest difficulty)
+def create_block(hashprev, coinbase, nTime=None):
+    block = CBlock()
+    if nTime is None:
+        import time
+        block.nTime = int(time.time()+600)
+    else:
+        block.nTime = nTime
+    block.hashPrevBlock = hashprev
+    block.nBits = 0x207fffff # Will break after a difficulty adjustment...
+    block.vtx.append(coinbase)
+    block.hashMerkleRoot = block.calc_merkle_root()
+    block.calc_sha256()
+    return block
+
+# From BIP141
+WITNESS_COMMITMENT_HEADER = b"\xaa\x21\xa9\xed"
+
+# According to BIP141, blocks with witness rules active must commit to the
+# hash of all in-block transactions including witness.
+def add_witness_commitment(block, nonce=0):
+    # First calculate the merkle root of the block's
+    # transactions, with witnesses.
+    witness_nonce = nonce
+    witness_root = block.calc_witness_merkle_root()
+    witness_commitment = uint256_from_str(hash256(ser_uint256(witness_root)+ser_uint256(witness_nonce)))
+    # witness_nonce should go to coinbase witness.
+    block.vtx[0].wit.vtxinwit = [CTxInWitness()]
+    block.vtx[0].wit.vtxinwit[0].scriptWitness.stack = [ser_uint256(witness_nonce)]
+
+    # witness commitment is the last OP_RETURN output in coinbase
+    output_data = WITNESS_COMMITMENT_HEADER + ser_uint256(witness_commitment)
+    block.vtx[0].vout.append(CTxOut(0, CScript([OP_RETURN, output_data])))
+    block.vtx[0].rehash()
+    block.hashMerkleRoot = block.calc_merkle_root()
+    block.rehash()
+
+
+def serialize_script_num(value):
+    r = bytearray(0)
+    if value == 0:
+        return r
+    neg = value < 0
+    absvalue = -value if neg else value
+    while (absvalue):
+        r.append(int(absvalue & 0xff))
+        absvalue >>= 8
+    if r[-1] & 0x80:
+        r.append(0x80 if neg else 0)
+    elif neg:
+        r[-1] |= 0x80
+    return r
+
+# Create a coinbase transaction, assuming no miner fees.
+# If pubkey is passed in, the coinbase output will be a P2PK output;
+# otherwise an anyone-can-spend output.
+def create_coinbase(height, pubkey = None):
+    coinbase = CTransaction()
+    coinbase.vin.append(CTxIn(COutPoint(0, 0xffffffff), 
+                ser_string(serialize_script_num(height)), 0xffffffff))
+    coinbaseoutput = CTxOut()
+    coinbaseoutput.nValue = 50 * COIN
+    halvings = int(height/150) # regtest
+    coinbaseoutput.nValue >>= halvings
+    if (pubkey != None):
+        coinbaseoutput.scriptPubKey = CScript([pubkey, OP_CHECKSIG])
+    else:
+        coinbaseoutput.scriptPubKey = CScript([OP_TRUE])
+    coinbase.vout = [ coinbaseoutput ]
+    coinbase.calc_sha256()
+    return coinbase
+
+# Create a transaction.
+# If the scriptPubKey is not specified, make it anyone-can-spend.
+def create_transaction(prevtx, n, sig, value, scriptPubKey=CScript()):
+    tx = CTransaction()
+    assert(n < len(prevtx.vout))
+    tx.vin.append(CTxIn(COutPoint(prevtx.sha256, n), sig, 0xffffffff))
+    tx.vout.append(CTxOut(value, scriptPubKey))
+    tx.calc_sha256()
+    return tx
+
+def get_legacy_sigopcount_block(block, fAccurate=True):
+    count = 0
+    for tx in block.vtx:
+        count += get_legacy_sigopcount_tx(tx, fAccurate)
+    return count
+
+def get_legacy_sigopcount_tx(tx, fAccurate=True):
+    count = 0
+    for i in tx.vout:
+        count += i.scriptPubKey.GetSigOpCount(fAccurate)
+    for j in tx.vin:
+        # scriptSig might be of type bytes, so convert to CScript for the moment
+        count += CScript(j.scriptSig).GetSigOpCount(fAccurate)
+    return count