input+sweep: let weightestimator take known TxOut

This commit is contained in:
Johan T. Halseth 2020-11-06 19:41:56 +01:00
parent efd6bc9501
commit 3d209059c1
No known key found for this signature in database
GPG Key ID: 15BAADA29DA20D26
3 changed files with 47 additions and 0 deletions

@ -533,6 +533,14 @@ func (twe *TxWeightEstimator) AddNestedP2WSHInput(witnessSize int) *TxWeightEsti
return twe
}
// AddTxOutput adds a known TxOut to the weight estimator.
func (twe *TxWeightEstimator) AddTxOutput(txOut *wire.TxOut) *TxWeightEstimator {
twe.outputSize += txOut.SerializeSize()
twe.outputCount++
return twe
}
// AddP2PKHOutput updates the weight estimate to account for an additional P2PKH
// output.
func (twe *TxWeightEstimator) AddP2PKHOutput() *TxWeightEstimator {

@ -2,6 +2,7 @@ package sweep
import (
"github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"github.com/lightningnetwork/lnd/input"
"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@ -92,6 +93,12 @@ func (w *weightEstimator) addP2WKHOutput() {
w.estimator.AddP2WKHOutput()
}
// addOutput updates the weight estimate to account for the known
// output given.
func (w *weightEstimator) addOutput(txOut *wire.TxOut) {
w.estimator.AddTxOutput(txOut)
}
// weight gets the estimated weight of the transaction.
func (w *weightEstimator) weight() int {
return w.estimator.Weight()

@ -3,7 +3,10 @@ package sweep
import (
"testing"
"github.com/btcsuite/btcd/chaincfg"
"github.com/btcsuite/btcd/txscript"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"github.com/lightningnetwork/lnd/input"
"github.com/lightningnetwork/lnd/lnwallet/chainfee"
"github.com/stretchr/testify/require"
@ -77,3 +80,32 @@ func TestWeightEstimator(t *testing.T) {
require.Equal(t, expectedFee, w.fee())
}
// TestWeightEstimatorAddOutput tests that adding the raw P2WKH output to the
// estimator yield the same result as an estimated add.
func TestWeightEstimatorAddOutput(t *testing.T) {
testFeeRate := chainfee.SatPerKWeight(20000)
p2wkhAddr, err := btcutil.NewAddressWitnessPubKeyHash(
make([]byte, 20), &chaincfg.MainNetParams,
)
require.NoError(t, err)
p2wkhScript, err := txscript.PayToAddrScript(p2wkhAddr)
require.NoError(t, err)
// Create two estimators, add the raw P2WKH out to one.
txOut := &wire.TxOut{
PkScript: p2wkhScript,
Value: 10000,
}
w1 := newWeightEstimator(testFeeRate)
w1.addOutput(txOut)
w2 := newWeightEstimator(testFeeRate)
w2.addP2WKHOutput()
// Estimate hhould be the same.
require.Equal(t, w1.weight(), w2.weight())
}