core: allow transfer 0 GAS/NEO with zero balance

This commit fixes states diff at 131795 block of mainnet.

Transaction:
```
NEO-GO-VM > loadbase64 DAAQDBSPsxdYh6cITC3gUKI4oWmYxJs49gwUj7MXWIenCEwt4FCiOKFpmMSbOPYUwB8MCHRyYW5zZmVyDBT1Y+pAvCg9TQ4FxI6jBbPyoHNA70FifVtSOQwAEQwUj7MXWIenCEwt4FCiOKFpmMSbOPYMFL1Mb4Fqp6gHiEwzM6xSc8fLS+RpFMAfDAh0cmFuc2ZlcgwU9WPqQLwoPU0OBcSOowWz8qBzQO9BYn1bUjk=
READY: loaded 176 instructions
NEO-GO-VM 0 > ops
INDEX    OPCODE       PARAMETER
0        PUSHDATA1     ("")                                       <<
2        PUSH0
3        PUSHDATA1    8fb3175887a7084c2de050a238a16998c49b38f6
25       PUSHDATA1    8fb3175887a7084c2de050a238a16998c49b38f6
47       PUSH4
48       PACK
49       PUSH15
50       PUSHDATA1    7472616e73666572 ("transfer")
60       PUSHDATA1    f563ea40bc283d4d0e05c48ea305b3f2a07340ef    // NEO token
82       SYSCALL      System.Contract.Call (627d5b52)
87       ASSERT
88       PUSHDATA1     ("")
90       PUSH1
91       PUSHDATA1    8fb3175887a7084c2de050a238a16998c49b38f6
113      PUSHDATA1    bd4c6f816aa7a807884c3333ac5273c7cb4be469
135      PUSH4
136      PACK
137      PUSH15
138      PUSHDATA1    7472616e73666572 ("transfer")
148      PUSHDATA1    f563ea40bc283d4d0e05c48ea305b3f2a07340ef    // NEO token
170      SYSCALL      System.Contract.Call (627d5b52)
175      ASSERT

```

Go's applog:
```
{
   "id" : 1,
   "result" : {
      "txid" : "0x97d2ccb01467b22c73a2cb95f7af298f3a5bd8c849d7044371898b8efecdaabd",
      "executions" : [
         {
            "exception" : "at instruction 87 (ASSERT): ASSERT failed",
            "stack" : [],
            "gasconsumed" : "4988995",
            "notifications" : [],
            "trigger" : "Application",
            "vmstate" : "FAULT"
         }
      ]
   },
   "jsonrpc" : "2.0"
}
```

C#'s applog:
```
{
   "jsonrpc" : "2.0",
   "result" : {
      "executions" : [
         {
            "stack" : [],
            "notifications" : [
               {
                  "contract" : "0xef4073a0f2b305a38ec4050e4d3d28bc40ea63f5",
                  "state" : {
                     "type" : "Array",
                     "value" : [
                        {
                           "type" : "ByteString",
                           "value" : "j7MXWIenCEwt4FCiOKFpmMSbOPY="
                        },
                        {
                           "type" : "ByteString",
                           "value" : "j7MXWIenCEwt4FCiOKFpmMSbOPY="
                        },
                        {
                           "value" : "0",
                           "type" : "Integer"
                        }
                     ]
                  },
                  "eventname" : "Transfer"
               },
               {
                  "contract" : "0xd2a4cff31913016155e38e474a2c06d08be276cf",
                  "state" : {
                     "value" : [
                        {
                           "type" : "Any"
                        },
                        {
                           "type" : "ByteString",
                           "value" : "vUxvgWqnqAeITDMzrFJzx8tL5Gk="
                        },
                        {
                           "value" : "2490",
                           "type" : "Integer"
                        }
                     ],
                     "type" : "Array"
                  },
                  "eventname" : "Transfer"
               },
               {
                  "contract" : "0xef4073a0f2b305a38ec4050e4d3d28bc40ea63f5",
                  "state" : {
                     "value" : [
                        {
                           "value" : "vUxvgWqnqAeITDMzrFJzx8tL5Gk=",
                           "type" : "ByteString"
                        },
                        {
                           "value" : "j7MXWIenCEwt4FCiOKFpmMSbOPY=",
                           "type" : "ByteString"
                        },
                        {
                           "value" : "1",
                           "type" : "Integer"
                        }
                     ],
                     "type" : "Array"
                  },
                  "eventname" : "Transfer"
               }
            ],
            "vmstate" : "HALT",
            "gasconsumed" : "9977990",
            "trigger" : "Application",
            "exception" : null
         }
      ],
      "txid" : "0x97d2ccb01467b22c73a2cb95f7af298f3a5bd8c849d7044371898b8efecdaabd"
   },
   "id" : 1
}

```
This commit is contained in:
Anna Shaleva 2021-09-10 17:18:09 +03:00
parent 04bbeccca6
commit 7fc57c9d58
2 changed files with 84 additions and 1 deletions

View file

@ -171,9 +171,13 @@ func (c *nep17TokenNative) updateAccBalance(ic *interop.Context, acc util.Uint16
key := makeAccountKey(acc) key := makeAccountKey(acc)
si := ic.DAO.GetStorageItem(c.ID, key) si := ic.DAO.GetStorageItem(c.ID, key)
if si == nil { if si == nil {
if amount.Sign() <= 0 { if amount.Sign() < 0 {
return errors.New("insufficient funds") return errors.New("insufficient funds")
} }
if amount.Sign() == 0 {
// it's OK to transfer 0 if the balance 0, no need to put si to the storage
return nil
}
si = state.StorageItem{} si = state.StorageItem{}
} }

View file

@ -6,6 +6,7 @@ import (
"sort" "sort"
"testing" "testing"
"github.com/nspcc-dev/neo-go/internal/random"
"github.com/nspcc-dev/neo-go/internal/testchain" "github.com/nspcc-dev/neo-go/internal/testchain"
"github.com/nspcc-dev/neo-go/pkg/config/netmode" "github.com/nspcc-dev/neo-go/pkg/config/netmode"
"github.com/nspcc-dev/neo-go/pkg/core/native" "github.com/nspcc-dev/neo-go/pkg/core/native"
@ -357,3 +358,81 @@ func TestNEO_Roundtrip(t *testing.T) {
require.Equal(t, bc.BlockHeight(), updatedHeight) require.Equal(t, bc.BlockHeight(), updatedHeight)
}) })
} }
func TestNEO_TransferZeroWithZeroBalance(t *testing.T) {
bc := newTestChain(t)
check := func(t *testing.T, roundtrip bool) {
acc := newAccountWithGAS(t, bc)
from := acc.PrivateKey().GetScriptHash()
to := from
if !roundtrip {
to = random.Uint160()
}
transferTx := newNEP17TransferWithAssert(bc.contracts.NEO.Hash, acc.PrivateKey().GetScriptHash(), to, 0, true)
transferTx.SystemFee = 100000000
transferTx.NetworkFee = 10000000
transferTx.ValidUntilBlock = bc.BlockHeight() + 1
addSigners(acc.PrivateKey().GetScriptHash(), transferTx)
require.NoError(t, acc.SignTx(bc.config.Magic, transferTx))
b := bc.newBlock(transferTx)
require.NoError(t, bc.AddBlock(b))
aer, err := bc.GetAppExecResults(transferTx.Hash(), trigger.Application)
require.NoError(t, err)
require.Equal(t, vm.HaltState, aer[0].VMState, aer[0].FaultException)
require.Len(t, aer[0].Events, 1) // roundtrip only, no GAS claim
require.Equal(t, stackitem.NewBigInteger(big.NewInt(0)), aer[0].Events[0].Item.Value().([]stackitem.Item)[2]) // amount is 0
// check balance wasn't changed and height wasn't updated
updatedBalance, updatedHeight := bc.GetGoverningTokenBalance(acc.PrivateKey().GetScriptHash())
require.Equal(t, big.NewInt(0), updatedBalance)
require.Equal(t, uint32(0), updatedHeight)
}
t.Run("roundtrip: amount == initial balance == 0", func(t *testing.T) {
check(t, true)
})
t.Run("non-roundtrip: amount == initial balance == 0", func(t *testing.T) {
check(t, false)
})
}
func TestNEO_TransferZeroWithNonZeroBalance(t *testing.T) {
bc := newTestChain(t)
check := func(t *testing.T, roundtrip bool) {
acc := newAccountWithGAS(t, bc)
transferTokenFromMultisigAccount(t, bc, acc.PrivateKey().GetScriptHash(), bc.contracts.NEO.Hash, 100)
initialBalance, _ := bc.GetGoverningTokenBalance(acc.PrivateKey().GetScriptHash())
require.True(t, initialBalance.Sign() > 0)
from := acc.PrivateKey().GetScriptHash()
to := from
if !roundtrip {
to = random.Uint160()
}
transferTx := newNEP17TransferWithAssert(bc.contracts.NEO.Hash, acc.PrivateKey().GetScriptHash(), to, 0, true)
transferTx.SystemFee = 100000000
transferTx.NetworkFee = 10000000
transferTx.ValidUntilBlock = bc.BlockHeight() + 1
addSigners(acc.PrivateKey().GetScriptHash(), transferTx)
require.NoError(t, acc.SignTx(bc.config.Magic, transferTx))
b := bc.newBlock(transferTx)
require.NoError(t, bc.AddBlock(b))
aer, err := bc.GetAppExecResults(transferTx.Hash(), trigger.Application)
require.NoError(t, err)
require.Equal(t, vm.HaltState, aer[0].VMState, aer[0].FaultException)
require.Len(t, aer[0].Events, 2) // roundtrip + GAS claim
require.Equal(t, stackitem.NewBigInteger(big.NewInt(0)), aer[0].Events[1].Item.Value().([]stackitem.Item)[2]) // amount is 0
// check balance wasn't changed and height was updated
updatedBalance, updatedHeight := bc.GetGoverningTokenBalance(acc.PrivateKey().GetScriptHash())
require.Equal(t, initialBalance, updatedBalance)
require.Equal(t, bc.BlockHeight(), updatedHeight)
}
t.Run("roundtrip", func(t *testing.T) {
check(t, true)
})
t.Run("non-roundtrip", func(t *testing.T) {
check(t, false)
})
}