htlcswitch: optimize tests to not tear down harness

htlcswitch/link_test.go

@@ -821,10 +821,6 @@ func TestExitNodeTimelockPayloadExceedsHTLC(t *testing.T) {
 func TestExitNodeHTLCUnderpaysPayloadAmount(t *testing.T) {
 	t.Parallel()
 
-	f := func(underpaymentRand uint64) bool {
-		underpayment := lnwire.MilliSatoshi(
-			underpaymentRand%(btcutil.SatoshiPerBitcoin-1) + 1,
-		)
 	channels, _, err := createClusterChannels(
 		t, btcutil.SatoshiPerBitcoin*5,
 		btcutil.SatoshiPerBitcoin*5,
@@ -839,7 +835,12 @@ func TestExitNodeHTLCUnderpaysPayloadAmount(t *testing.T) {
 	require.NoError(t, n.start())
 	t.Cleanup(n.stop)
 
-		const amount = btcutil.SatoshiPerBitcoin
+	f := func(underpaymentRand uint64) bool {
+		const amount = btcutil.SatoshiPerBitcoin / 100
+		underpayment := lnwire.MilliSatoshi(
+			underpaymentRand%(amount-1) + 1,
+		)
+
 		htlcAmt, htlcExpiry, hops := generateHops(
 			amount, testStartingHeight, n.firstBobChannelLink,
 		)
@@ -858,7 +859,7 @@ func TestExitNodeHTLCUnderpaysPayloadAmount(t *testing.T) {
 
 		return err != nil
 	}
-	err := quick.Check(f, &quick.Config{MaxCount: 20})
+	err = quick.Check(f, nil)
 	require.NoError(t, err, "payment should have failed but didn't")
 }
 
@@ -868,10 +869,6 @@ func TestExitNodeHTLCUnderpaysPayloadAmount(t *testing.T) {
 func TestExitNodeHTLCExceedsAmountPayload(t *testing.T) {
 	t.Parallel()
 
-	f := func(overpaymentRand uint64) bool {
-		overpayment := lnwire.MilliSatoshi(
-			overpaymentRand%(btcutil.SatoshiPerBitcoin-1) + 1,
-		)
 	channels, _, err := createClusterChannels(
 		t, btcutil.SatoshiPerBitcoin*5,
 		btcutil.SatoshiPerBitcoin*5,
@@ -884,7 +881,12 @@ func TestExitNodeHTLCExceedsAmountPayload(t *testing.T) {
 	require.NoError(t, n.start())
 	t.Cleanup(n.stop)
 
-		const amount = btcutil.SatoshiPerBitcoin
+	f := func(overpaymentRand uint64) bool {
+		const amount = btcutil.SatoshiPerBitcoin / 100
+		overpayment := lnwire.MilliSatoshi(
+			overpaymentRand%(amount-1) + 1,
+		)
+
 		htlcAmt, htlcExpiry, hops := generateHops(amount,
 			testStartingHeight, n.firstBobChannelLink)
 
@@ -901,7 +903,7 @@ func TestExitNodeHTLCExceedsAmountPayload(t *testing.T) {
 
 		return err == nil
 	}
-	err := quick.Check(f, &quick.Config{MaxCount: 20})
+	err = quick.Check(f, nil)
 	require.NoError(t, err, "payment should have succeeded but didn't")
 }