Method update_fee

test/functional/feature_block.py:1366–1376

(self, tx, prev_tx, prev_n)

    # update the fee output amount and also move it to the end
    def update_fee(self, tx, prev_tx, prev_n):
        total_out = 0
        for i in reversed(range(len(tx.vout))):
            if tx.vout[i].is_fee():
                del tx.vout[i]
            else:
                total_out += tx.vout[i].nValue.getAmount()
        fee = prev_tx.vout[prev_n].nValue.getAmount() - total_out
        if fee > 0:
            tx.vout.append(CTxOut(fee))
        tx.calc_sha256()

    # sign a transaction, using the key we know about
    # this signs input 0 in tx, which is assumed to be spending output 0 in spend_tx