import { ECSignature, SignedOrder, ZeroEx } from '0x.js'; import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils'; import { ExchangeContractErrs } from '@0xproject/types'; import { BigNumber } from '@0xproject/utils'; import { Web3Wrapper } from '@0xproject/web3-wrapper'; import * as chai from 'chai'; import ethUtil = require('ethereumjs-util'); import * as Web3 from 'web3'; import { ArbitrageContract } from '../../src/contract_wrappers/generated/arbitrage'; import { EtherDeltaContract } from '../../src/contract_wrappers/generated/ether_delta'; import { ExchangeContract } from '../../src/contract_wrappers/generated/exchange'; import { Balances } from '../../util/balances'; import { constants } from '../../util/constants'; import { crypto } from '../../util/crypto'; import { ExchangeWrapper } from '../../util/exchange_wrapper'; import { OrderFactory } from '../../util/order_factory'; import { BalancesByOwner, ContractName } from '../../util/types'; import { chaiSetup } from '../utils/chai_setup'; import { deployer } from '../utils/deployer'; import { provider, web3Wrapper } from '../utils/web3_wrapper'; chaiSetup.configure(); const expect = chai.expect; const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper); describe('Arbitrage', () => { let coinbase: string; let maker: string; let edMaker: string; let edFrontRunner: string; let amountGet: BigNumber; let amountGive: BigNumber; let makerTokenAmount: BigNumber; let takerTokenAmount: BigNumber; const feeRecipient = ZeroEx.NULL_ADDRESS; const INITIAL_BALANCE = ZeroEx.toBaseUnitAmount(new BigNumber(10000), 18); const INITIAL_ALLOWANCE = ZeroEx.toBaseUnitAmount(new BigNumber(10000), 18); let weth: Web3.ContractInstance; let zrx: Web3.ContractInstance; let arbitrage: ArbitrageContract; let etherDelta: EtherDeltaContract; let signedOrder: SignedOrder; let exWrapper: ExchangeWrapper; let orderFactory: OrderFactory; let zeroEx: ZeroEx; // From a bird's eye view - we create two orders. // 0x order of 1 ZRX (maker) for 1 WETH (taker) // ED order of 2 WETH (tokenGive) for 1 ZRX (tokenGet) // And then we do an atomic arbitrage between them which gives us 1 WETH. before(async () => { const accounts = await web3Wrapper.getAvailableAddressesAsync(); [coinbase, maker, edMaker, edFrontRunner] = accounts; weth = await deployer.deployAsync(ContractName.DummyToken, constants.DUMMY_TOKEN_ARGS); zrx = await deployer.deployAsync(ContractName.DummyToken, constants.DUMMY_TOKEN_ARGS); const accountLevels = await deployer.deployAsync(ContractName.AccountLevels); const edAdminAddress = accounts[0]; const edMakerFee = 0; const edTakerFee = 0; const edFeeRebate = 0; const etherDeltaInstance = await deployer.deployAsync(ContractName.EtherDelta, [ edAdminAddress, feeRecipient, accountLevels.address, edMakerFee, edTakerFee, edFeeRebate, ]); etherDelta = new EtherDeltaContract(etherDeltaInstance.abi, etherDeltaInstance.address, provider); const tokenTransferProxy = await deployer.deployAsync(ContractName.TokenTransferProxy); const exchangeInstance = await deployer.deployAsync(ContractName.Exchange, [ zrx.address, tokenTransferProxy.address, ]); await tokenTransferProxy.addAuthorizedAddress(exchangeInstance.address, { from: accounts[0] }); zeroEx = new ZeroEx(provider, { exchangeContractAddress: exchangeInstance.address, networkId: constants.TESTRPC_NETWORK_ID, }); const exchange = new ExchangeContract(exchangeInstance.abi, exchangeInstance.address, provider); exWrapper = new ExchangeWrapper(exchange, zeroEx); makerTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(1), 18); takerTokenAmount = makerTokenAmount; const defaultOrderParams = { exchangeContractAddress: exchange.address, maker, feeRecipient, makerTokenAddress: zrx.address, takerTokenAddress: weth.address, makerTokenAmount, takerTokenAmount, makerFee: new BigNumber(0), takerFee: new BigNumber(0), }; orderFactory = new OrderFactory(zeroEx, defaultOrderParams); const arbitrageInstance = await deployer.deployAsync(ContractName.Arbitrage, [ exchange.address, etherDelta.address, tokenTransferProxy.address, ]); arbitrage = new ArbitrageContract(arbitrageInstance.abi, arbitrageInstance.address, provider); // Enable arbitrage and withdrawals of tokens await arbitrage.setAllowances.sendTransactionAsync(weth.address, { from: coinbase }); await arbitrage.setAllowances.sendTransactionAsync(zrx.address, { from: coinbase }); // Give some tokens to arbitrage contract await weth.setBalance(arbitrage.address, takerTokenAmount, { from: coinbase }); // Fund the maker on exchange side await zrx.setBalance(maker, makerTokenAmount, { from: coinbase }); // Set the allowance for the maker on Exchange side await zrx.approve(tokenTransferProxy.address, INITIAL_ALLOWANCE, { from: maker }); amountGive = ZeroEx.toBaseUnitAmount(new BigNumber(2), 18); // Fund the maker on EtherDelta side await weth.setBalance(edMaker, amountGive, { from: coinbase }); // Set the allowance for the maker on EtherDelta side await weth.approve(etherDelta.address, INITIAL_ALLOWANCE, { from: edMaker }); // Deposit maker funds into EtherDelta await etherDelta.depositToken.sendTransactionAsync(weth.address, amountGive, { from: edMaker }); amountGet = makerTokenAmount; // Fund the front runner on EtherDelta side await zrx.setBalance(edFrontRunner, amountGet, { from: coinbase }); // Set the allowance for the front-runner on EtherDelta side await zrx.approve(etherDelta.address, INITIAL_ALLOWANCE, { from: edFrontRunner }); // Deposit front runner funds into EtherDelta await etherDelta.depositToken.sendTransactionAsync(zrx.address, amountGet, { from: edFrontRunner }); }); beforeEach(async () => { await blockchainLifecycle.startAsync(); }); afterEach(async () => { await blockchainLifecycle.revertAsync(); }); describe('makeAtomicTrade', () => { let addresses: string[]; let values: BigNumber[]; let v: number[]; let r: string[]; let s: string[]; let tokenGet: string; let tokenGive: string; let expires: BigNumber; let nonce: BigNumber; let edSignature: ECSignature; before(async () => { signedOrder = await orderFactory.newSignedOrderAsync(); tokenGet = zrx.address; tokenGive = weth.address; const blockNumber = await web3Wrapper.getBlockNumberAsync(); const ED_ORDER_EXPIRATION_IN_BLOCKS = 10; expires = new BigNumber(blockNumber + ED_ORDER_EXPIRATION_IN_BLOCKS); nonce = new BigNumber(42); const edOrderHash = `0x${crypto .solSHA256([etherDelta.address, tokenGet, amountGet, tokenGive, amountGive, expires, nonce]) .toString('hex')}`; const shouldAddPersonalMessagePrefix = false; edSignature = await zeroEx.signOrderHashAsync(edOrderHash, edMaker, shouldAddPersonalMessagePrefix); addresses = [ signedOrder.maker, signedOrder.taker, signedOrder.makerTokenAddress, signedOrder.takerTokenAddress, signedOrder.feeRecipient, edMaker, ]; const fillTakerTokenAmount = takerTokenAmount; const edFillAmount = makerTokenAmount; values = [ signedOrder.makerTokenAmount, signedOrder.takerTokenAmount, signedOrder.makerFee, signedOrder.takerFee, signedOrder.expirationUnixTimestampSec, signedOrder.salt, fillTakerTokenAmount, amountGet, amountGive, expires, nonce, edFillAmount, ]; v = [signedOrder.ecSignature.v, edSignature.v]; r = [signedOrder.ecSignature.r, edSignature.r]; s = [signedOrder.ecSignature.s, edSignature.s]; }); it('should successfully execute the arbitrage if not front-runned', async () => { const txHash = await arbitrage.makeAtomicTrade.sendTransactionAsync(addresses, values, v, r, s, { from: coinbase, }); const res = await zeroEx.awaitTransactionMinedAsync(txHash); const postBalance = await weth.balanceOf(arbitrage.address); expect(postBalance).to.be.bignumber.equal(amountGive); }); it('should fail and revert if front-runned', async () => { const preBalance = await weth.balanceOf(arbitrage.address); // Front-running transaction await etherDelta.trade.sendTransactionAsync( tokenGet, amountGet, tokenGive, amountGive, expires, nonce, edMaker, edSignature.v, edSignature.r, edSignature.s, amountGet, { from: edFrontRunner }, ); // tslint:disable-next-line:await-promise await expect( arbitrage.makeAtomicTrade.sendTransactionAsync(addresses, values, v, r, s, { from: coinbase }), ).to.be.rejectedWith(constants.REVERT); const postBalance = await weth.balanceOf(arbitrage.address); expect(preBalance).to.be.bignumber.equal(postBalance); }); }); });