path: root/packages/contracts/test/ts/zrxToken.ts

import {ZeroEx} from '0x.js';
import {BigNumber} from 'bignumber.js';
import * as chai from 'chai';
import Web3 = require('web3');

import {Artifacts} from '../../util/artifacts';
import {ContractInstance} from '../../util/types';

import {chaiSetup} from './utils/chai_setup';

chaiSetup.configure();
const expect = chai.expect;
const {Exchange, ZRXToken} = new Artifacts(artifacts);
const web3: Web3 = (global as any).web3;

contract('ZRXToken', (accounts: string[]) => {
  const owner = accounts[0];
  const spender = accounts[1];
  let zeroEx: ZeroEx;

  let MAX_UINT: BigNumber;

  let zrx: ContractInstance;
  let zrxAddress: string;

  beforeEach(async () => {
    zeroEx = new ZeroEx(web3.currentProvider, {
        exchangeContractAddress: Exchange.address,
    });
    zrxAddress = await zeroEx.exchange.getZRXTokenAddressAsync();
    zrx = await ZRXToken.at(zrxAddress);
    MAX_UINT = zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
  });

  describe('constants', () => {
    it('should have 18 decimals', async () => {
      const decimals = new BigNumber(await zrx.decimals.call());
      const expectedDecimals = 18;
      expect(decimals).to.be.bignumber.equal(expectedDecimals);
    });

    it('should have a total supply of 1 billion tokens', async () => {
      const totalSupply = new BigNumber(await zrx.totalSupply.call());
      const expectedTotalSupply = 1000000000;
      expect(ZeroEx.toUnitAmount(totalSupply, 18)).to.be.bignumber.equal(expectedTotalSupply);
    });

    it('should be named 0x Protocol Token', async () => {
      const name = await zrx.name.call();
      const expectedName = '0x Protocol Token';
      expect(name).to.be.equal(expectedName);
    });

    it('should have the symbol ZRX', async () => {
      const symbol = await zrx.symbol.call();
      const expectedSymbol = 'ZRX';
      expect(symbol).to.be.equal(expectedSymbol);
    });
  });

  describe('constructor', () => {
    it('should initialize owner balance to totalSupply', async () => {
      const ownerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const totalSupply = new BigNumber(await zrx.totalSupply.call());
      expect(totalSupply).to.be.bignumber.equal(ownerBalance);
    });
  });

  describe('transfer', () => {
    it('should transfer balance from sender to receiver', async () => {
      const receiver = spender;
      const initOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const amountToTransfer = new BigNumber(1);
      const txHash = await zeroEx.token.transferAsync(zrxAddress, owner, receiver, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);
      const finalOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const finalReceiverBalance = await zeroEx.token.getBalanceAsync(zrxAddress, receiver);

      const expectedFinalOwnerBalance = initOwnerBalance.minus(amountToTransfer);
      const expectedFinalReceiverBalance = amountToTransfer;
      expect(finalOwnerBalance).to.be.bignumber.equal(expectedFinalOwnerBalance);
      expect(finalReceiverBalance).to.be.bignumber.equal(expectedFinalReceiverBalance);
    });

    it('should return true on a 0 value transfer', async () => {
      const didReturnTrue = await zrx.transfer.call(spender, 0, {from: owner});
      expect(didReturnTrue).to.be.true();
    });
  });

  describe('transferFrom', () => {
    it('should return false if owner has insufficient balance', async () => {
      const ownerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const amountToTransfer = ownerBalance.plus(1);
      let txHash = await zeroEx.token.setAllowanceAsync(zrxAddress, owner, spender, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);
      const didReturnTrue = await zrx.transferFrom.call(owner, spender, amountToTransfer, {from: spender});
      expect(didReturnTrue).to.be.false();
      // Reset allowance
      txHash = await zeroEx.token.setAllowanceAsync(zrxAddress, owner, spender, new BigNumber(0));
      await zeroEx.awaitTransactionMinedAsync(txHash);
    });

    it('should return false if spender has insufficient allowance', async () => {
      const ownerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const amountToTransfer = ownerBalance;

      const spenderAllowance = await zeroEx.token.getAllowanceAsync(zrxAddress, owner, spender);
      const spenderAllowanceIsInsufficient = spenderAllowance.cmp(amountToTransfer) < 0;
      expect(spenderAllowanceIsInsufficient).to.be.true();

      const didReturnTrue = await zrx.transferFrom.call(owner, spender, amountToTransfer, {from: spender});
      expect(didReturnTrue).to.be.false();
    });

    it('should return true on a 0 value transfer', async () => {
      const amountToTransfer = 0;
      const didReturnTrue = await zrx.transferFrom.call(owner, spender, amountToTransfer, {from: spender});
      expect(didReturnTrue).to.be.true();
    });

    it('should not modify spender allowance if spender allowance is 2^256 - 1', async () => {
      const initOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const amountToTransfer = initOwnerBalance;
      const initSpenderAllowance = MAX_UINT;
      let txHash = await zeroEx.token.setAllowanceAsync(zrxAddress, owner, spender, initSpenderAllowance);
      await zeroEx.awaitTransactionMinedAsync(txHash);
      txHash = await zeroEx.token.transferFromAsync(zrxAddress, owner, spender, spender, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);

      const newSpenderAllowance = await zeroEx.token.getAllowanceAsync(zrxAddress, owner, spender);
      expect(initSpenderAllowance).to.be.bignumber.equal(newSpenderAllowance);
      // Restore balance
      txHash = await zeroEx.token.transferAsync(zrxAddress, spender, owner, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);
    });

    it('should transfer the correct balances if spender has sufficient allowance', async () => {
      const initOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const initSpenderBalance = await zeroEx.token.getBalanceAsync(zrxAddress, spender);
      const amountToTransfer = initOwnerBalance;
      const initSpenderAllowance = initOwnerBalance;
      let txHash = await zeroEx.token.setAllowanceAsync(zrxAddress, owner, spender, initSpenderAllowance);
      await zeroEx.awaitTransactionMinedAsync(txHash);
      txHash = await zeroEx.token.transferFromAsync(zrxAddress, owner, spender, spender, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);

      const newOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const newSpenderBalance = await zeroEx.token.getBalanceAsync(zrxAddress, spender);

      expect(newOwnerBalance).to.be.bignumber.equal(0);
      expect(newSpenderBalance).to.be.bignumber.equal(initSpenderBalance.plus(initOwnerBalance));
    });

    it('should modify allowance if spender has sufficient allowance less than 2^256 - 1', async () => {
      const initOwnerBalance = await zeroEx.token.getBalanceAsync(zrxAddress, owner);
      const amountToTransfer = initOwnerBalance;
      const initSpenderAllowance = initOwnerBalance;
      let txHash = await zeroEx.token.setAllowanceAsync(zrxAddress, owner, spender, initSpenderAllowance);
      await zeroEx.awaitTransactionMinedAsync(txHash);
      txHash = await zeroEx.token.transferFromAsync(zrxAddress, owner, spender, spender, amountToTransfer);
      await zeroEx.awaitTransactionMinedAsync(txHash);

      const newSpenderAllowance = await zeroEx.token.getAllowanceAsync(zrxAddress, owner, spender);
      expect(newSpenderAllowance).to.be.bignumber.equal(0);
    });
  });
});