convert lane and nonce to uint64 (#157)

actors/builtin/paych/paych_actor.go

@@ -102,9 +102,9 @@ type SignedVoucher struct {
 	// (optional) Extra can be specified by `From` to add a verification method to the voucher
 	Extra *ModVerifyParams
 	// Specifies which lane the Voucher merges into (will be created if does not exist)
-	Lane int64
+	Lane uint64
 	// Nonce is set by `From` to prevent redemption of stale vouchers on a lane
-	Nonce int64
+	Nonce uint64
 	// Amount voucher can be redeemed for
 	Amount big.Int
 	// (optional) MinSettleHeight can extend channel MinSettleHeight if needed
@@ -324,11 +324,11 @@ func (t *SignedVoucher) SigningBytes() ([]byte, error) {
 }
 
 // Returns the insertion index for a lane ID, with the matching lane state if found, or nil.
-func findLane(lanes []*LaneState, ID int64) (int, *LaneState) {
+func findLane(lanes []*LaneState, ID uint64) (int, *LaneState) {
 	insertionIdx := sort.Search(len(lanes), func(i int) bool {
 		return lanes[i].ID >= ID
 	})
-	if insertionIdx == len(lanes) || lanes[insertionIdx].ID != int64(insertionIdx) {
+	if insertionIdx == len(lanes) || lanes[insertionIdx].ID != uint64(insertionIdx) {
 		// Not found
 		return insertionIdx, nil
 	}

actors/builtin/paych/paych_state.go

@@ -31,15 +31,15 @@ type State struct {
 // The Lane state tracks the latest (highest) voucher nonce used to merge the lane
 // as well as the amount it has already redeemed.
 type LaneState struct {
-	ID       int64 // Unique to this channel
+	ID       uint64 // Unique to this channel
 	Redeemed big.Int
-	Nonce    int64
+	Nonce    uint64
 }
 
 // Specifies which `Lane`s to be merged with what `Nonce` on channelUpdate
 type Merge struct {
-	Lane  int64
-	Nonce int64
+	Lane  uint64
+	Nonce uint64
 }
 
 func ConstructState(from addr.Address, to addr.Address) *State {

actors/builtin/paych/paych_test.go

@@ -111,8 +111,8 @@ func TestPaymentChannelActor_UpdateChannelState(t *testing.T) {
 		rt := builder.Build(t)
 		actor.constructAndVerify(rt, payerAddr, newPaychAddr)
 		amt := big.NewInt(10)
-		lane := int64(999)
-		nonce := int64(1)
+		lane := uint64(999)
+		nonce := uint64(1)
 		sig := &crypto.Signature{
 			Type: crypto.SigTypeBLS,
 			Data: []byte("doesn't matter"),
@@ -144,8 +144,8 @@ func TestPaymentChannelActor_UpdateChannelState(t *testing.T) {
 		actor.constructAndVerify(rt, payerAddr, newPaychAddr)
 		tl := abi.ChainEpoch(10)
 		amt := big.NewInt(9)
-		lane := int64(8)
-		nonce := int64(7)
+		lane := uint64(8)
+		nonce := uint64(7)
 		sig := &crypto.Signature{
 			Type: crypto.SigTypeBLS,
 			Data: []byte("doesn't matter"),