/* eslint-disable */ const { BN, constants, expectRevert, time } = require('@openzeppelin/test-helpers'); const { expect } = require('chai'); const { MAX_UINT256 } = constants; const { fromRpcSig } = require('ethereumjs-util'); const ethSigUtil = require('eth-sig-util'); const Wallet = require('ethereumjs-wallet').default; const ERC20Permit = artifacts.require('$ERC20Permit'); const { Permit, getDomain, domainType, domainSeparator } = require('../../../helpers/eip712'); const { getChainId } = require('../../../helpers/chainid'); contract('ERC20Permit', function (accounts) { const [initialHolder, spender] = accounts; const name = 'My Token'; const symbol = 'MTKN'; const version = '1'; const initialSupply = new BN(100); beforeEach(async function () { this.chainId = await getChainId(); this.token = await ERC20Permit.new(name, symbol, name); await this.token.$_mint(initialHolder, initialSupply); }); it('initial nonce is 0', async function () { expect(await this.token.nonces(initialHolder)).to.be.bignumber.equal('0'); }); it('domain separator', async function () { expect(await this.token.DOMAIN_SEPARATOR()).to.equal(await getDomain(this.token).then(domainSeparator)); }); describe('permit', function () { const wallet = Wallet.generate(); const owner = wallet.getAddressString(); const value = new BN(42); const nonce = 0; const maxDeadline = MAX_UINT256; const buildData = (contract, deadline = maxDeadline) => getDomain(contract).then(domain => ({ primaryType: 'Permit', types: { EIP712Domain: domainType(domain), Permit }, domain, message: { owner, spender, value, nonce, deadline }, })); it('accepts owner signature', async function () { const { v, r, s } = await buildData(this.token) .then(data => ethSigUtil.signTypedMessage(wallet.getPrivateKey(), { data })) .then(fromRpcSig); await this.token.permit(owner, spender, value, maxDeadline, v, r, s); expect(await this.token.nonces(owner)).to.be.bignumber.equal('1'); expect(await this.token.allowance(owner, spender)).to.be.bignumber.equal(value); }); it('rejects reused signature', async function () { const { v, r, s } = await buildData(this.token) .then(data => ethSigUtil.signTypedMessage(wallet.getPrivateKey(), { data })) .then(fromRpcSig); await this.token.permit(owner, spender, value, maxDeadline, v, r, s); await expectRevert( this.token.permit(owner, spender, value, maxDeadline, v, r, s), 'ERC20Permit: invalid signature', ); }); it('rejects other signature', async function () { const otherWallet = Wallet.generate(); const { v, r, s } = await buildData(this.token) .then(data => ethSigUtil.signTypedMessage(otherWallet.getPrivateKey(), { data })) .then(fromRpcSig); await expectRevert( this.token.permit(owner, spender, value, maxDeadline, v, r, s), 'ERC20Permit: invalid signature', ); }); it('rejects expired permit', async function () { const deadline = (await time.latest()) - time.duration.weeks(1); const { v, r, s } = await buildData(this.token, deadline) .then(data => ethSigUtil.signTypedMessage(wallet.getPrivateKey(), { data })) .then(fromRpcSig); await expectRevert(this.token.permit(owner, spender, value, deadline, v, r, s), 'ERC20Permit: expired deadline'); }); }); });