test: introduce and use CTransaction .wtxid_int property

This commits removes the `.calc_sha256` method from the CTransaction
and introduces a property `.wtxid_int` property as replacement.

test/functional/p2p_compactblocks.py

@@ -365,7 +365,7 @@ class CompactBlocksTest(BitcoinTestFramework):
                 # Already checked prefilled transactions above
                 header_and_shortids.prefilled_txn.pop(0)
             else:
-                tx_hash = block.vtx[index].calc_sha256(True)
+                tx_hash = block.vtx[index].wtxid_int
                 shortid = calculate_shortid(k0, k1, tx_hash)
                 assert_equal(shortid, header_and_shortids.shortids[0])
                 header_and_shortids.shortids.pop(0)
@@ -395,7 +395,7 @@ class CompactBlocksTest(BitcoinTestFramework):
             comp_block.header = CBlockHeader(block)
             comp_block.nonce = 0
             [k0, k1] = comp_block.get_siphash_keys()
-            coinbase_hash = block.vtx[0].calc_sha256(True)
+            coinbase_hash = block.vtx[0].wtxid_int
             comp_block.shortids = [calculate_shortid(k0, k1, coinbase_hash)]
             test_node.send_and_ping(msg_cmpctblock(comp_block.to_p2p()))
             assert_equal(int(node.getbestblockhash(), 16), block.hashPrevBlock)

test/functional/p2p_segwit.py

@@ -174,7 +174,7 @@ class TestP2PConn(P2PInterface):
         with p2p_lock:
             self.last_message.pop("getdata", None)
         if use_wtxid:
-            wtxid = tx.calc_sha256(True)
+            wtxid = tx.wtxid_int
             self.send_without_ping(msg_inv(inv=[CInv(MSG_WTX, wtxid)]))
         else:
             self.send_without_ping(msg_inv(inv=[CInv(MSG_TX, tx.sha256)]))
@@ -1979,7 +1979,7 @@ class SegWitTest(BitcoinTestFramework):
         self.wtx_node.announce_tx_and_wait_for_getdata(tx2, use_wtxid=True)
         with p2p_lock:
             lgd = self.wtx_node.lastgetdata[:]
-        assert_equal(lgd, [CInv(MSG_WTX, tx2.calc_sha256(True))])
+        assert_equal(lgd, [CInv(MSG_WTX, tx2.wtxid_int)])
 
         # Announce Segwit transaction from non wtxidrelay peer
         # and wait for getdata

test/functional/p2p_tx_privacy.py

@@ -71,7 +71,7 @@ class TxPrivacyTest(BitcoinTestFramework):
 
         # Spy should only get an inv for the second transaction as the first
         # one was received pre-verack with the spy
-        spy.wait_for_inv_match(CInv(MSG_WTX, tx2.calc_sha256(True)))
+        spy.wait_for_inv_match(CInv(MSG_WTX, tx2.wtxid_int))
 
 if __name__ == '__main__':
     TxPrivacyTest(__file__).main()

test/functional/test_framework/blocktools.py

@@ -107,7 +107,7 @@ def create_block(hashprev=None, coinbase=None, ntime=None, *, version=None, tmpl
     block.vtx.append(coinbase)
     if txlist:
         for tx in txlist:
-            if not hasattr(tx, 'calc_sha256'):
+            if type(tx) is str:
                 tx = tx_from_hex(tx)
             block.vtx.append(tx)
     block.hashMerkleRoot = block.calc_merkle_root()

test/functional/test_framework/messages.py

@@ -658,8 +658,14 @@ class CTransaction:
         return self.serialize_with_witness()
 
     def getwtxid(self):
+        """Return wtxid (transaction hash with witness) as hex string."""
         return hash256(self.serialize())[::-1].hex()
 
+    @property
+    def wtxid_int(self):
+        """Return wtxid (transaction hash with witness) as integer."""
+        return uint256_from_str(hash256(self.serialize_with_witness()))
+
     @property
     def hash(self):
         """Return txid (transaction hash without witness) as hex string."""
@@ -675,12 +681,6 @@ class CTransaction:
     def rehash(self):
         return self.hash
 
-    # TODO: get rid of this method, replace call-sites by .wtxid_int access (not introduced yet)
-    def calc_sha256(self, with_witness=False):
-        if with_witness:
-            # Don't cache the result, just return it
-            return uint256_from_str(hash256(self.serialize_with_witness()))
-
     def is_valid(self):
         for tout in self.vout:
             if tout.nValue < 0 or tout.nValue > 21000000 * COIN:
@@ -819,7 +819,7 @@ class CBlock(CBlockHeader):
 
         for tx in self.vtx[1:]:
             # Calculate the hashes with witness data
-            hashes.append(ser_uint256(tx.calc_sha256(True)))
+            hashes.append(ser_uint256(tx.wtxid_int))
 
         return self.get_merkle_root(hashes)
 
@@ -1003,7 +1003,7 @@ class HeaderAndShortIDs:
             if i not in prefill_list:
                 tx_hash = block.vtx[i].sha256
                 if use_witness:
-                    tx_hash = block.vtx[i].calc_sha256(with_witness=True)
+                    tx_hash = block.vtx[i].wtxid_int
                 self.shortids.append(calculate_shortid(k0, k1, tx_hash))
 
     def __repr__(self):