path: root/core/vm/governance_test.go

// Copyright 2018 The dexon-consensus Authors
// This file is part of the dexon-consensus library.
//
// The dexon-consensus library is free software: you can redistribute it
// and/or modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the License,
// or (at your option) any later version.
//
// The dexon-consensus library is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
// General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the dexon-consensus library. If not, see
// <http://www.gnu.org/licenses/>.

package vm

import (
    "bytes"
    "crypto/ecdsa"
    "math/big"
    "math/rand"
    "sort"
    "testing"
    "time"

    coreCommon "github.com/dexon-foundation/dexon-consensus/common"
    coreCrypto "github.com/dexon-foundation/dexon-consensus/core/crypto"
    coreEcdsa "github.com/dexon-foundation/dexon-consensus/core/crypto/ecdsa"
    coreTypes "github.com/dexon-foundation/dexon-consensus/core/types"
    coreUtils "github.com/dexon-foundation/dexon-consensus/core/utils"

    "github.com/dexon-foundation/dexon/common"
    "github.com/dexon-foundation/dexon/core/state"
    "github.com/dexon-foundation/dexon/crypto"
    "github.com/dexon-foundation/dexon/ethdb"
    "github.com/dexon-foundation/dexon/params"
    "github.com/dexon-foundation/dexon/rlp"
    "github.com/stretchr/testify/suite"
)

func init() {
    rand.Seed(time.Now().UnixNano())
}

func randomBytes(minLength, maxLength int32) []byte {
    length := rand.Int31()%(maxLength-minLength) + minLength
    b := make([]byte, length)
    for i := range b {
        b[i] = byte(65 + rand.Int31()%60)
    }
    return b
}

type GovernanceStateHelperTestSuite struct {
    suite.Suite

    s *GovernanceStateHelper
}

func (g *GovernanceStateHelperTestSuite) SetupTest() {
    db := state.NewDatabase(ethdb.NewMemDatabase())
    statedb, err := state.New(common.Hash{}, db)
    if err != nil {
        panic(err)
    }
    g.s = &GovernanceStateHelper{statedb}
}

func (g *GovernanceStateHelperTestSuite) TestReadWriteBytes() {
    for i := 0; i < 100; i++ {
        // Short bytes.
        loc := big.NewInt(rand.Int63())
        data := randomBytes(3, 32)
        g.s.writeBytes(loc, data)
        read := g.s.readBytes(loc)
        g.Require().Equal(0, bytes.Compare(data, read))

        // long bytes.
        loc = big.NewInt(rand.Int63())
        data = randomBytes(33, 2560)
        g.s.writeBytes(loc, data)
        read = g.s.readBytes(loc)
        g.Require().Equal(0, bytes.Compare(data, read))
    }
}

func TestGovernanceStateHelper(t *testing.T) {
    suite.Run(t, new(GovernanceStateHelperTestSuite))
}

type GovernanceContractTestSuite struct {
    suite.Suite

    config  *params.DexconConfig
    memDB   *ethdb.MemDatabase
    stateDB *state.StateDB
    s       *GovernanceStateHelper
}

func (g *GovernanceContractTestSuite) SetupTest() {
    memDB := ethdb.NewMemDatabase()
    stateDB, err := state.New(common.Hash{}, state.NewDatabase(memDB))
    if err != nil {
        panic(err)
    }
    g.memDB = memDB
    g.stateDB = stateDB
    g.s = &GovernanceStateHelper{stateDB}

    config := params.TestnetChainConfig.Dexcon
    config.LockupPeriod = 1000
    config.NextHalvingSupply = new(big.Int).Mul(big.NewInt(1e18), big.NewInt(2.5e9))
    config.LastHalvedAmount = new(big.Int).Mul(big.NewInt(1e18), big.NewInt(1.5e9))
    config.MiningVelocity = 0.1875

    g.config = config

    // Give governance contract balance so it will not be deleted because of being an empty state object.
    stateDB.AddBalance(GovernanceContractAddress, big.NewInt(1))

    // Genesis CRS.
    crs := crypto.Keccak256Hash([]byte(config.GenesisCRSText))
    g.s.PushCRS(crs)

    // Round 0 height.
    g.s.PushRoundHeight(big.NewInt(0))

    // Owner.
    g.s.SetOwner(g.config.Owner)

    // Governance configuration.
    g.s.UpdateConfiguration(config)

    g.stateDB.Commit(true)
}

func (g *GovernanceContractTestSuite) newPrefundAccount() (*ecdsa.PrivateKey, common.Address) {
    privKey, err := crypto.GenerateKey()
    if err != nil {
        panic(err)
    }
    address := crypto.PubkeyToAddress(privKey.PublicKey)

    g.stateDB.AddBalance(address, new(big.Int).Mul(big.NewInt(1e18), big.NewInt(2e6)))
    return privKey, address
}

func (g *GovernanceContractTestSuite) call(caller common.Address, input []byte, value *big.Int) ([]byte, error) {
    context := Context{
        CanTransfer: func(db StateDB, addr common.Address, amount *big.Int) bool {
            return db.GetBalance(addr).Cmp(amount) >= 0
        },
        Transfer: func(db StateDB, sender common.Address, recipient common.Address, amount *big.Int) {
            db.SubBalance(sender, amount)
            db.AddBalance(recipient, amount)
        },
        GetRoundHeight: func(round uint64) (uint64, bool) {
            switch round {
            case 0:
                return 0, true
            case 1:
                return 1000, true
            case 2:
                return 2000, true
            }
            return 0, false
        },
        Time:        big.NewInt(time.Now().UnixNano() / 1000000),
        BlockNumber: big.NewInt(0),
    }

    evm := NewEVM(context, g.stateDB, params.TestChainConfig, Config{IsBlockProposer: true})
    ret, _, err := evm.Call(AccountRef(caller), GovernanceContractAddress, input, 10000000, value)
    return ret, err
}

func (g *GovernanceContractTestSuite) TestTransferOwnership() {
    _, addr := g.newPrefundAccount()

    input, err := abiObject.Pack("transferOwnership", addr)
    g.Require().NoError(err)

    // Call with non-owner.
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Call with owner.
    _, err = g.call(g.config.Owner, input, big.NewInt(0))
    g.Require().NoError(err)
    g.Require().Equal(addr, g.s.Owner())
}

func (g *GovernanceContractTestSuite) TestStakeUnstakeWithoutExtraDelegators() {
    privKey, addr := g.newPrefundAccount()
    pk := crypto.FromECDSAPub(&privKey.PublicKey)

    // Stake.
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(1e6))
    balanceBeforeStake := g.stateDB.GetBalance(addr)
    input, err := abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    g.Require().Equal(1, int(g.s.LenNodes().Uint64()))
    g.Require().Equal(1, len(g.s.QualifiedNodes()))
    g.Require().Equal("Test1", g.s.Node(big.NewInt(0)).Name)
    g.Require().Equal(amount.String(), g.s.TotalStaked().String())

    // Check balance.
    g.Require().Equal(new(big.Int).Sub(balanceBeforeStake, amount), g.stateDB.GetBalance(addr))
    g.Require().Equal(new(big.Int).Add(big.NewInt(1), amount), g.stateDB.GetBalance(GovernanceContractAddress))

    // Staking again should fail.
    _, err = g.call(addr, input, amount)
    g.Require().NotNil(err)

    // Unstake.
    input, err = abiObject.Pack("unstake")
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    g.Require().Equal(0, len(g.s.QualifiedNodes()))
    g.Require().Equal(1, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(1, int(g.s.LenNodes().Uint64()))

    node := g.s.Node(big.NewInt(0))
    g.Require().Equal(big.NewInt(0).String(), node.Staked.String())
    g.Require().Equal(big.NewInt(0).String(), g.s.TotalStaked().String())

    // Wait for lockup time than withdraw.
    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(0, len(g.s.QualifiedNodes()))
    g.Require().Equal(0, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(0, int(g.s.LenNodes().Uint64()))

    // Stake 2 nodes, and unstake the first then the second.

    // 2nd node Stake.
    privKey2, addr2 := g.newPrefundAccount()
    pk2 := crypto.FromECDSAPub(&privKey2.PublicKey)
    input, err = abiObject.Pack("stake", pk2, "Test2", "test2@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr2, input, amount)
    g.Require().NoError(err)
    g.Require().Equal("Test2", g.s.Node(big.NewInt(0)).Name)
    g.Require().Equal(0, int(g.s.NodesOffsetByAddress(addr2).Int64()))

    // 1st node Stake.
    input, err = abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    g.Require().Equal(2, len(g.s.QualifiedNodes()))
    g.Require().Equal(new(big.Int).Mul(amount, big.NewInt(2)).String(), g.s.TotalStaked().String())

    // 2nd node Unstake.
    input, err = abiObject.Pack("unstake")
    g.Require().NoError(err)
    _, err = g.call(addr2, input, big.NewInt(0))
    g.Require().NoError(err)
    node = g.s.Node(big.NewInt(0))
    g.Require().Equal("Test2", node.Name)
    g.Require().Equal(big.NewInt(0).String(), node.Staked.String())
    g.Require().Equal(1, len(g.s.QualifiedNodes()))
    g.Require().Equal(amount.String(), g.s.TotalStaked().String())

    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr2)
    g.Require().NoError(err)
    _, err = g.call(addr2, input, big.NewInt(0))
    g.Require().NoError(err)
    g.Require().Equal(1, len(g.s.QualifiedNodes()))

    g.Require().Equal(1, int(g.s.LenNodes().Uint64()))
    g.Require().Equal("Test1", g.s.Node(big.NewInt(0)).Name)
    g.Require().Equal(-1, int(g.s.NodesOffsetByAddress(addr2).Int64()))

    // 1st node Unstake.
    input, err = abiObject.Pack("unstake")
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    g.Require().Equal(0, len(g.s.QualifiedNodes()))
    g.Require().Equal(big.NewInt(0).String(), g.s.TotalStaked().String())

    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(0, int(g.s.LenNodes().Uint64()))
    g.Require().Equal(-1, int(g.s.NodesOffsetByAddress(addr).Int64()))
    g.Require().Equal(-1, int(g.s.DelegatorsOffset(addr, addr).Int64()))

    // Check balance.
    g.Require().Equal(balanceBeforeStake, g.stateDB.GetBalance(addr))
    g.Require().Equal(balanceBeforeStake, g.stateDB.GetBalance(addr2))
    g.Require().Equal(big.NewInt(1), g.stateDB.GetBalance(GovernanceContractAddress))
}

func (g *GovernanceContractTestSuite) TestDelegateUndelegate() {
    privKey, addr := g.newPrefundAccount()
    pk := crypto.FromECDSAPub(&privKey.PublicKey)

    // Stake.
    input, err := abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    ownerStaked := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    _, err = g.call(addr, input, ownerStaked)
    g.Require().NoError(err)
    g.Require().Equal(0, len(g.s.QualifiedNodes()))
    g.Require().Equal(addr, g.s.Delegator(addr, big.NewInt(0)).Owner)
    g.Require().Equal(ownerStaked, g.s.Node(big.NewInt(0)).Staked)

    // 1st delegator delegate to 1st node.
    _, addrDelegator := g.newPrefundAccount()

    balanceBeforeDelegate := g.stateDB.GetBalance(addrDelegator)
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(3e5))
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)

    _, err = g.call(addrDelegator, input, amount)
    g.Require().NoError(err)
    g.Require().Equal(new(big.Int).Sub(balanceBeforeDelegate, amount), g.stateDB.GetBalance(addrDelegator))
    g.Require().Equal(addrDelegator, g.s.Delegator(addr, big.NewInt(1)).Owner)
    g.Require().Equal(new(big.Int).Add(amount, ownerStaked), g.s.Node(big.NewInt(0)).Staked)
    g.Require().Equal(g.s.Node(big.NewInt(0)).Staked.String(), g.s.TotalStaked().String())
    g.Require().Equal(1, int(g.s.DelegatorsOffset(addr, addrDelegator).Int64()))

    // Same person delegate the 2nd time should fail.
    _, err = g.call(addrDelegator, input, big.NewInt(1e18))
    g.Require().NotNil(err)

    // Not yet qualified.
    g.Require().Equal(0, len(g.s.QualifiedNodes()))

    // 2nd delegator delegate to 1st node.
    _, addrDelegator2 := g.newPrefundAccount()
    _, err = g.call(addrDelegator2, input, amount)
    g.Require().NoError(err)
    g.Require().Equal(new(big.Int).Sub(balanceBeforeDelegate, amount), g.stateDB.GetBalance(addrDelegator2))
    g.Require().Equal(addrDelegator2, g.s.Delegator(addr, big.NewInt(2)).Owner)
    g.Require().Equal(new(big.Int).Add(ownerStaked, new(big.Int).Mul(amount, big.NewInt(2))),
        g.s.Node(big.NewInt(0)).Staked)
    g.Require().Equal(g.s.Node(big.NewInt(0)).Staked.String(), g.s.TotalStaked().String())
    g.Require().Equal(2, int(g.s.DelegatorsOffset(addr, addrDelegator2).Int64()))

    // Qualified.
    g.Require().Equal(1, len(g.s.QualifiedNodes()))

    // Undelegate addrDelegator.
    balanceBeforeUnDelegate := g.stateDB.GetBalance(addrDelegator)
    input, err = abiObject.Pack("undelegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().Equal(new(big.Int).Add(amount, ownerStaked), g.s.Node(big.NewInt(0)).Staked)
    g.Require().Equal(g.s.Node(big.NewInt(0)).Staked.String(), g.s.TotalStaked().String())
    g.Require().NoError(err)

    // Undelegate the second time should fail.
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().Error(err)

    // Withdraw within lockup time should fail.
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().NotNil(err)

    g.Require().Equal(3, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(balanceBeforeUnDelegate, g.stateDB.GetBalance(addrDelegator))
    g.Require().NotEqual(-1, int(g.s.DelegatorsOffset(addr, addrDelegator).Int64()))

    // Wait for lockup time than withdraw.
    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(2, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(new(big.Int).Add(balanceBeforeUnDelegate, amount), g.stateDB.GetBalance(addrDelegator))
    g.Require().Equal(-1, int(g.s.DelegatorsOffset(addr, addrDelegator).Int64()))

    // Withdraw when their is no delegation should fail.
    time.Sleep(time.Second)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().Error(err)

    // Undelegate addrDelegator2.
    balanceBeforeUnDelegate = g.stateDB.GetBalance(addrDelegator2)
    input, err = abiObject.Pack("undelegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator2, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(ownerStaked, g.s.Node(big.NewInt(0)).Staked)
    g.Require().Equal(g.s.Node(big.NewInt(0)).Staked.String(), g.s.TotalStaked().String())

    // Wait for lockup time than withdraw.
    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator2, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(1, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(new(big.Int).Add(balanceBeforeUnDelegate, amount), g.stateDB.GetBalance(addrDelegator2))
    g.Require().Equal(-1, int(g.s.DelegatorsOffset(addr, addrDelegator2).Int64()))

    // Unqualified
    g.Require().Equal(0, len(g.s.QualifiedNodes()))

    // Owner undelegate itself.
    g.Require().Equal(1, int(g.s.LenNodes().Uint64()))
    g.Require().Equal(1, int(g.s.LenDelegators(addr).Uint64()))

    input, err = abiObject.Pack("undelegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    g.Require().Equal(big.NewInt(0).String(), g.s.Node(big.NewInt(0)).Staked.String())
    g.Require().Equal(big.NewInt(0).String(), g.s.TotalStaked().String())

    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))

    g.Require().Equal(0, int(g.s.LenNodes().Uint64()))
    g.Require().Equal(0, int(g.s.LenDelegators(addr).Uint64()))
}

func (g *GovernanceContractTestSuite) TestFine() {
    privKey, addr := g.newPrefundAccount()
    pk := crypto.FromECDSAPub(&privKey.PublicKey)

    // Stake.
    input, err := abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    ownerStaked := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    _, err = g.call(addr, input, ownerStaked)
    g.Require().NoError(err)
    g.Require().Equal(0, len(g.s.QualifiedNodes()))
    g.Require().Equal(addr, g.s.Delegator(addr, big.NewInt(0)).Owner)
    g.Require().Equal(ownerStaked, g.s.Node(big.NewInt(0)).Staked)

    // 1st delegator delegate to 1st node.
    _, addrDelegator := g.newPrefundAccount()

    balanceBeforeDelegate := g.stateDB.GetBalance(addrDelegator)
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)

    _, err = g.call(addrDelegator, input, amount)
    g.Require().NoError(err)
    g.Require().Equal(new(big.Int).Sub(balanceBeforeDelegate, amount), g.stateDB.GetBalance(addrDelegator))
    g.Require().Equal(addrDelegator, g.s.Delegator(addr, big.NewInt(1)).Owner)
    g.Require().Equal(new(big.Int).Add(amount, ownerStaked), g.s.Node(big.NewInt(0)).Staked)
    g.Require().Equal(1, int(g.s.DelegatorsOffset(addr, addrDelegator).Int64()))

    // Qualified.
    g.Require().Equal(1, len(g.s.QualifiedNodes()))

    // Paying to node without fine should fail.
    input, err = abiObject.Pack("payFine", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, amount)
    g.Require().NotNil(err)

    // Fined.
    offset := g.s.NodesOffsetByAddress(addr)
    g.Require().True(offset.Cmp(big.NewInt(0)) >= 0)
    node := g.s.Node(offset)
    node.Fined = new(big.Int).Set(amount)
    g.s.UpdateNode(offset, node)
    node = g.s.Node(offset)
    g.Require().Equal(0, node.Fined.Cmp(amount))

    // Not qualified after fined.
    g.Require().Equal(0, len(g.s.QualifiedNodes()))

    // Cannot undelegate before fines are paied.
    input, err = abiObject.Pack("undelegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Only delegators can pay fine.
    _, addrDelegator2 := g.newPrefundAccount()
    input, err = abiObject.Pack("payFine", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator2, input, big.NewInt(5e5))
    g.Require().NotNil(err)

    // Paying more than fine should fail.
    payAmount := new(big.Int).Add(amount, amount)
    input, err = abiObject.Pack("payFine", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, payAmount)
    g.Require().NotNil(err)

    // Pay the fine.
    input, err = abiObject.Pack("payFine", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, amount)
    g.Require().NoError(err)

    // Qualified.
    g.Require().Equal(1, len(g.s.QualifiedNodes()))

    // Can undelegate after all fines are paied.
    input, err = abiObject.Pack("undelegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().NoError(err)
}

func (g *GovernanceContractTestSuite) TestUnstakeWithExtraDelegators() {
    privKey, addr := g.newPrefundAccount()
    pk := crypto.FromECDSAPub(&privKey.PublicKey)

    // Stake.
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    input, err := abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    // 1st delegator delegate to 1st node.
    _, addrDelegator := g.newPrefundAccount()

    balanceBeforeDelegate := g.stateDB.GetBalance(addrDelegator)
    amount = new(big.Int).Mul(big.NewInt(1e18), big.NewInt(3e5))
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)

    _, err = g.call(addrDelegator, input, amount)
    g.Require().NoError(err)
    g.Require().Equal(new(big.Int).Sub(balanceBeforeDelegate, amount), g.stateDB.GetBalance(addrDelegator))
    g.Require().Equal(addrDelegator, g.s.Delegator(addr, big.NewInt(1)).Owner)
    g.Require().Equal(0, len(g.s.QualifiedNodes()))

    // 2st delegator delegate to 1st node.
    _, addrDelegator2 := g.newPrefundAccount()

    balanceBeforeDelegate = g.stateDB.GetBalance(addrDelegator2)
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)

    _, err = g.call(addrDelegator2, input, amount)
    g.Require().NoError(err)
    g.Require().Equal(new(big.Int).Sub(balanceBeforeDelegate, amount), g.stateDB.GetBalance(addrDelegator2))
    g.Require().Equal(addrDelegator2, g.s.Delegator(addr, big.NewInt(2)).Owner)

    // Node is now qualified.
    g.Require().Equal(1, len(g.s.QualifiedNodes()))

    // Unstake.
    input, err = abiObject.Pack("unstake")
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    time.Sleep(time.Second * 2)
    input, err = abiObject.Pack("withdraw", addr)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, big.NewInt(0))
    g.Require().NoError(err)
    _, err = g.call(addrDelegator2, input, big.NewInt(0))
    g.Require().NoError(err)

    g.Require().Equal(0, int(g.s.LenDelegators(addr).Uint64()))
    g.Require().Equal(0, int(g.s.LenNodes().Uint64()))

    // Check balance.
    g.Require().Equal(balanceBeforeDelegate, g.stateDB.GetBalance(addr))
    g.Require().Equal(balanceBeforeDelegate, g.stateDB.GetBalance(addrDelegator))
    g.Require().Equal(balanceBeforeDelegate, g.stateDB.GetBalance(addrDelegator2))
    g.Require().Equal(big.NewInt(1), g.stateDB.GetBalance(GovernanceContractAddress))
}

func (g *GovernanceContractTestSuite) TestUpdateConfiguration() {
    _, addr := g.newPrefundAccount()

    input, err := abiObject.Pack("updateConfiguration",
        new(big.Int).Mul(big.NewInt(1e18), big.NewInt(1e6)),
        big.NewInt(1000),
        big.NewInt(8000000),
        big.NewInt(6),
        big.NewInt(250),
        big.NewInt(2500),
        big.NewInt(0),
        big.NewInt(667000),
        big.NewInt(4),
        big.NewInt(4),
        big.NewInt(600000),
        big.NewInt(900),
        []*big.Int{big.NewInt(1), big.NewInt(1), big.NewInt(1)})
    g.Require().NoError(err)

    // Call with non-owner.
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Call with owner.
    _, err = g.call(g.config.Owner, input, big.NewInt(0))
    g.Require().NoError(err)
}

func (g *GovernanceContractTestSuite) TestSnapshotRound() {
    _, addr := g.newPrefundAccount()

    // Wrong height.
    input, err := abiObject.Pack("snapshotRound", big.NewInt(1), big.NewInt(666))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Invalid round.
    input, err = abiObject.Pack("snapshotRound", big.NewInt(2), big.NewInt(2000))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Correct.
    input, err = abiObject.Pack("snapshotRound", big.NewInt(1), big.NewInt(1000))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    // Duplicate round.
    input, err = abiObject.Pack("snapshotRound", big.NewInt(1), big.NewInt(1000))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Invalid round.
    input, err = abiObject.Pack("snapshotRound", big.NewInt(3), big.NewInt(3000))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NotNil(err)

    // Correct.
    input, err = abiObject.Pack("snapshotRound", big.NewInt(2), big.NewInt(2000))
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
}

func (g *GovernanceContractTestSuite) TestConfigurationReading() {
    _, addr := g.newPrefundAccount()

    // CRS.
    input, err := abiObject.Pack("crs", big.NewInt(0))
    g.Require().NoError(err)
    res, err := g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    var crs0 [32]byte
    err = abiObject.Unpack(&crs0, "crs", res)
    g.Require().NoError(err)
    g.Require().Equal(crypto.Keccak256Hash([]byte(g.config.GenesisCRSText)), common.BytesToHash(crs0[:]))

    // Owner.
    input, err = abiObject.Pack("owner")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    var owner common.Address
    err = abiObject.Unpack(&owner, "owner", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.Owner, owner)

    // MinStake.
    input, err = abiObject.Pack("minStake")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    var value *big.Int
    err = abiObject.Unpack(&value, "minStake", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.MinStake.String(), value.String())

    // BlockReward.
    input, err = abiObject.Pack("miningVelocity")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "miningVelocity", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.MiningVelocity, float32(value.Uint64())/decimalMultiplier)

    // BlockGasLimit.
    input, err = abiObject.Pack("blockGasLimit")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "blockGasLimit", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.BlockGasLimit, value.Uint64())

    // NumChains.
    input, err = abiObject.Pack("numChains")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "numChains", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.NumChains, uint32(value.Uint64()))

    // LambdaBA.
    input, err = abiObject.Pack("lambdaBA")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "lambdaBA", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.LambdaBA, value.Uint64())

    // LambdaDKG.
    input, err = abiObject.Pack("lambdaDKG")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "lambdaDKG", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.LambdaDKG, value.Uint64())

    // K.
    input, err = abiObject.Pack("k")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "k", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.K, uint32(value.Uint64()))

    // PhiRatio.
    input, err = abiObject.Pack("phiRatio")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "phiRatio", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.PhiRatio, float32(value.Uint64())/decimalMultiplier)

    // NotarySetSize.
    input, err = abiObject.Pack("notarySetSize")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "notarySetSize", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.NotarySetSize, uint32(value.Uint64()))

    // DKGSetSize.
    input, err = abiObject.Pack("dkgSetSize")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "dkgSetSize", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.DKGSetSize, uint32(value.Uint64()))

    // RoundInterval.
    input, err = abiObject.Pack("roundInterval")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "roundInterval", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.RoundInterval, value.Uint64())

    // MinBlockInterval.
    input, err = abiObject.Pack("minBlockInterval")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "minBlockInterval", res)
    g.Require().NoError(err)
    g.Require().Equal(g.config.MinBlockInterval, value.Uint64())
}

func (g *GovernanceContractTestSuite) TestReportForkVote() {
    key, addr := g.newPrefundAccount()
    pkBytes := crypto.FromECDSAPub(&key.PublicKey)

    // Stake.
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    input, err := abiObject.Pack("stake", pkBytes, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    pubKey := coreEcdsa.NewPublicKeyFromECDSA(&key.PublicKey)
    privKey := coreEcdsa.NewPrivateKeyFromECDSA(key)
    vote1 := coreTypes.NewVote(coreTypes.VoteCom, coreCommon.NewRandomHash(), uint64(0))
    vote1.ProposerID = coreTypes.NewNodeID(pubKey)

    vote2 := vote1.Clone()
    for vote2.BlockHash == vote1.BlockHash {
        vote2.BlockHash = coreCommon.NewRandomHash()
    }
    vote1.Signature, err = privKey.Sign(coreUtils.HashVote(vote1))
    g.Require().NoError(err)
    vote2.Signature, err = privKey.Sign(coreUtils.HashVote(vote2))
    g.Require().NoError(err)

    vote1Bytes, err := rlp.EncodeToBytes(vote1)
    g.Require().NoError(err)
    vote2Bytes, err := rlp.EncodeToBytes(vote2)
    g.Require().NoError(err)

    // Report wrong type (fork block)
    input, err = abiObject.Pack("report", big.NewInt(2), vote1Bytes, vote2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().Error(err)

    input, err = abiObject.Pack("report", big.NewInt(1), vote1Bytes, vote2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    node := g.s.Node(big.NewInt(0))
    g.Require().Equal(node.Fined, g.s.FineValue(big.NewInt(1)))

    // Duplicate report should fail.
    input, err = abiObject.Pack("report", big.NewInt(1), vote1Bytes, vote2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().Error(err)

    // Check if finedRecords is set.
    payloads := [][]byte{vote1Bytes, vote2Bytes}
    sort.Sort(sortBytes(payloads))

    hash := Bytes32(crypto.Keccak256Hash(payloads...))
    input, err = abiObject.Pack("finedRecords", hash)
    g.Require().NoError(err)
    res, err := g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    var value bool
    err = abiObject.Unpack(&value, "finedRecords", res)
    g.Require().NoError(err)
    g.Require().True(value)
}

func (g *GovernanceContractTestSuite) TestReportForkBlock() {
    key, addr := g.newPrefundAccount()
    pkBytes := crypto.FromECDSAPub(&key.PublicKey)

    // Stake.
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    input, err := abiObject.Pack("stake", pkBytes, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    privKey := coreEcdsa.NewPrivateKeyFromECDSA(key)
    block1 := &coreTypes.Block{
        ProposerID: coreTypes.NewNodeID(privKey.PublicKey()),
        ParentHash: coreCommon.NewRandomHash(),
        Timestamp:  time.Now(),
    }

    block2 := block1.Clone()
    for block2.ParentHash == block1.ParentHash {
        block2.ParentHash = coreCommon.NewRandomHash()
    }

    hashBlock := func(block *coreTypes.Block) coreCommon.Hash {
        block.PayloadHash = coreCrypto.Keccak256Hash(block.Payload)
        var err error
        block.Hash, err = coreUtils.HashBlock(block)
        g.Require().NoError(err)
        return block.Hash
    }

    block1.Signature, err = privKey.Sign(hashBlock(block1))
    g.Require().NoError(err)
    block2.Signature, err = privKey.Sign(hashBlock(block2))
    g.Require().NoError(err)

    block1Bytes, err := rlp.EncodeToBytes(block1)
    g.Require().NoError(err)
    block2Bytes, err := rlp.EncodeToBytes(block2)
    g.Require().NoError(err)

    // Report wrong type (fork vote)
    input, err = abiObject.Pack("report", big.NewInt(1), block1Bytes, block2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().Error(err)

    input, err = abiObject.Pack("report", big.NewInt(2), block1Bytes, block2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    node := g.s.Node(big.NewInt(0))
    g.Require().Equal(node.Fined, g.s.FineValue(big.NewInt(2)))

    // Duplicate report should fail.
    input, err = abiObject.Pack("report", big.NewInt(2), block1Bytes, block2Bytes)
    g.Require().NoError(err)
    _, err = g.call(addr, input, big.NewInt(0))
    g.Require().Error(err)

    // Check if finedRecords is set.
    payloads := [][]byte{block1Bytes, block2Bytes}
    sort.Sort(sortBytes(payloads))

    hash := Bytes32(crypto.Keccak256Hash(payloads...))
    input, err = abiObject.Pack("finedRecords", hash)
    g.Require().NoError(err)
    res, err := g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    var value bool
    err = abiObject.Unpack(&value, "finedRecords", res)
    g.Require().NoError(err)
    g.Require().True(value)
}

func (g *GovernanceContractTestSuite) TestMiscVariableReading() {
    privKey, addr := g.newPrefundAccount()
    pk := crypto.FromECDSAPub(&privKey.PublicKey)

    input, err := abiObject.Pack("totalSupply")
    g.Require().NoError(err)
    res, err := g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    input, err = abiObject.Pack("totalStaked")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    // Stake.
    amount := new(big.Int).Mul(big.NewInt(1e18), big.NewInt(5e5))
    input, err = abiObject.Pack("stake", pk, "Test1", "test1@dexon.org", "Taipei, Taiwan", "https://dexon.org")
    g.Require().NoError(err)
    _, err = g.call(addr, input, amount)
    g.Require().NoError(err)

    // 1st delegator delegate to 1st node.
    _, addrDelegator := g.newPrefundAccount()
    amount = new(big.Int).Mul(big.NewInt(1e18), big.NewInt(3e5))
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator, input, amount)
    g.Require().NoError(err)

    // 2st delegator delegate to 1st node.
    _, addrDelegator2 := g.newPrefundAccount()
    input, err = abiObject.Pack("delegate", addr)
    g.Require().NoError(err)
    _, err = g.call(addrDelegator2, input, amount)
    g.Require().NoError(err)

    input, err = abiObject.Pack("nodes", big.NewInt(0))
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    input, err = abiObject.Pack("nodesLength")
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    var value *big.Int
    err = abiObject.Unpack(&value, "nodesLength", res)
    g.Require().NoError(err)
    g.Require().Equal(1, int(value.Uint64()))

    input, err = abiObject.Pack("nodesOffsetByAddress", addr)
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "nodesOffsetByAddress", res)
    g.Require().NoError(err)
    g.Require().Equal(0, int(value.Uint64()))

    id, err := publicKeyToNodeID(pk)
    g.Require().NoError(err)
    input, err = abiObject.Pack("nodesOffsetByID", id)
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "nodesOffsetByID", res)
    g.Require().NoError(err)
    g.Require().Equal(0, int(value.Uint64()))

    input, err = abiObject.Pack("delegators", addr, big.NewInt(0))
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)

    input, err = abiObject.Pack("delegatorsLength", addr)
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "delegatorsLength", res)
    g.Require().NoError(err)
    g.Require().Equal(3, int(value.Uint64()))

    input, err = abiObject.Pack("delegatorsOffset", addr, addrDelegator2)
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
    err = abiObject.Unpack(&value, "delegatorsOffset", res)
    g.Require().NoError(err)
    g.Require().Equal(2, int(value.Uint64()))

    input, err = abiObject.Pack("fineValues", big.NewInt(0))
    g.Require().NoError(err)
    res, err = g.call(addr, input, big.NewInt(0))
    g.Require().NoError(err)
}

func (g *GovernanceContractTestSuite) TestHalvingCondition() {
    // TotalSupply 2.5B reached
    g.s.MiningHalved()
    g.Require().Equal(new(big.Int).Mul(big.NewInt(1e18), big.NewInt(3.25e9)).String(),
        g.s.NextHalvingSupply().String())
    g.Require().Equal(new(big.Int).Mul(big.NewInt(1e18), big.NewInt(0.75e9)).String(),
        g.s.LastHalvedAmount().String())

    // TotalSupply 3.25B reached
    g.s.MiningHalved()
    g.Require().Equal(new(big.Int).Mul(big.NewInt(1e18), big.NewInt(3.625e9)).String(),
        g.s.NextHalvingSupply().String())
    g.Require().Equal(new(big.Int).Mul(big.NewInt(1e18), big.NewInt(0.375e9)).String(),
        g.s.LastHalvedAmount().String())
}

func TestGovernanceContract(t *testing.T) {
    suite.Run(t, new(GovernanceContractTestSuite))
}