Get rid of tx_total_outputs_value()

src/jmbitcoin/secp256k1_transaction.py

@@ -184,15 +184,6 @@ def tx_vsize(tx):
     non_witness_size = raw_tx_size - witness_size
     return ceil(non_witness_size + .25 * witness_size)
 
-def tx_total_outputs_value(tx: CTransaction) -> int:
-    """
-    Returns sum of all transaction outputs value in satoshis.
-    """
-    tx_out_sum = 0
-    for txout in tx.vout:
-        tx_out_sum = tx_out_sum + txout.nValue
-    return tx_out_sum
-
 def pubkey_to_p2pkh_script(pub, require_compressed=False):
     """
     Given a pubkey in bytes, return a CScript

src/jmclient/maker.py

@@ -179,7 +179,7 @@ def on_tx_received(self, nick, tx, offerinfo):
             sigs.append(base64.b64encode(sigmsg).decode('ascii'))
         return (True, sigs)
 
-    def verify_unsigned_tx(self, tx, offerinfo):
+    def verify_unsigned_tx(self, tx: btc.CTransaction, offerinfo):
         """This code is security-critical.
         Before signing the transaction the Maker must ensure
         that all details are as expected, and most importantly
@@ -191,10 +191,9 @@ def verify_unsigned_tx(self, tx, offerinfo):
 
         if self.minimum_tx_fee_rate > 1000:
             tx_inp_data = jm_single().bc_interface.query_utxo_set(tx_utxo_set)
-            total_input_value_sum = 0
-            for utxo in tx_inp_data:
-                total_input_value_sum = total_input_value_sum + utxo["value"]
-            tx_fee = total_input_value_sum - btc.tx_total_outputs_value(tx)
+            total_input_value_sum = sum([x["value"] for x in tx_inp_data])
+            total_output_value_sum = sum([x.nValue for x in tx.vout])
+            tx_fee = total_input_value_sum - total_output_value_sum
             tx_fee_rate = tx_fee / btc.tx_vsize(tx) * 1000
             if tx_fee_rate < self.minimum_tx_fee_rate:
                 return (False, "tx feerate below configured minimum tx feerate")

test/jmbitcoin/test_tx_signing.py

@@ -85,7 +85,6 @@ def test_sign_standard_txs(addrtype):
     txin = btc.CTxIn(btc.COutPoint(txid[::-1], vout))
     txout = btc.CTxOut(amount_less_fee, target_scriptPubKey)
     tx = btc.CMutableTransaction([txin], [txout])
-    assert btc.tx_total_outputs_value(tx) == amount_less_fee
 
     # Calculate the signature hash for the transaction. This is then signed by the
     # private key that controls the UTXO being spent here at this txin_index.