chainfee: method to round up the fee for a given transaction weight

lnwallet/chainfee/rates_test.go

@@ -3,6 +3,7 @@ package chainfee
 import (
 	"testing"
 
+	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/stretchr/testify/require"
 )
 
@@ -20,3 +21,13 @@ func TestSatPerVByteConversion(t *testing.T) {
 	// 1 sat/vb should be equal to 250 sat/kw.
 	require.Equal(t, SatPerKWeight(250), rate.FeePerKWeight())
 }
+
+// TestFeeForWeightRoundUp checks that the FeeForWeightRoundUp method correctly
+// rounds up the fee for a given weight.
+func TestFeeForWeightRoundUp(t *testing.T) {
+	feeRate := SatPerVByte(1).FeePerKWeight()
+	txWeight := lntypes.WeightUnit(674) // 674 weight units is 168.5 vb.
+
+	require.EqualValues(t, 168, feeRate.FeeForWeight(txWeight))
+	require.EqualValues(t, 169, feeRate.FeeForWeightRoundUp(txWeight))
+}