milksad
/
rust-bitcoin-unsafe-fast
14
0
Fork 0
Code Issues Pull Requests Activity

Use InputWeightPrediction to calculate effective_value 

InputWeightPrediction can be used to determine the weight needed
to calculate the effective_value.  This simplifies the process for api
consumers by allowing an easier interface with which to use to predict
the weight.  Prior to this change, it was required to manually calculate
the predicted weight for whichever input type was to be used.
This commit is contained in:
yancy 2024-02-06 18:31:20 +01:00 committed by yancy
parent 265f9ebee0
commit f6105ea417
1 changed files with 9 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
bitcoin/src/blockdata/transaction.rs
View File

@ -772,13 +772,13 @@ impl Decodable for Transaction {
/// # Parameters
///
/// * `fee_rate` - the fee rate of the transaction being created.
/// * `satisfaction_weight` - satisfied spending conditions weight.
/// * `input_weight_prediction` - the predicted input weight.
pub fn effective_value(
fee_rate: FeeRate,
satisfaction_weight: Weight,
input_weight_prediction: InputWeightPrediction,
value: Amount,
) -> Option<SignedAmount> {
let weight = satisfaction_weight.checked_add(TX_IN_BASE_WEIGHT)?;
let weight = input_weight_prediction.total_weight();
let signed_input_fee = fee_rate.to_fee(weight)?.to_signed();
value.to_signed().checked_sub(signed_input_fee)
}
@ -1651,24 +1651,19 @@ mod tests {
fn effective_value_happy_path() {
let value = "1 cBTC".parse::<Amount>().unwrap();
let fee_rate = FeeRate::from_sat_per_kwu(10);
let satisfaction_weight = Weight::from_wu(204);
let effective_value = effective_value(fee_rate, satisfaction_weight, value).unwrap();
let effective_value =
effective_value(fee_rate, InputWeightPrediction::P2WPKH_MAX, value).unwrap();
// 10 sat/kwu * (204wu + BASE_WEIGHT) = 4 sats
let expected_fee = "4 sats".parse::<SignedAmount>().unwrap();
// 10 sat/kwu * 272 wu = 4 sats (rounding up)
let expected_fee = "3 sats".parse::<SignedAmount>().unwrap();
let expected_effective_value = (value.to_signed() - expected_fee).unwrap();
assert_eq!(effective_value, expected_effective_value);
}
#[test]
fn effective_value_fee_rate_does_not_overflow() {
let eff_value = effective_value(FeeRate::MAX, Weight::ZERO, Amount::ZERO);
assert!(eff_value.is_none());
}
#[test]
fn effective_value_weight_does_not_overflow() {
let eff_value = effective_value(FeeRate::ZERO, Weight::MAX, Amount::ZERO);
let eff_value =
effective_value(FeeRate::MAX, InputWeightPrediction::P2WPKH_MAX, Amount::ZERO);
assert!(eff_value.is_none());
}