import { MaxUint160, MaxUint256 } from '@uniswap/permit2-sdk' import { DAI, USDC_MAINNET } from '../../src/constants/tokens' import { getTestSelector } from '../utils' const APPROVE_BUTTON = '[data-testid="swap-approve-button"]' /** Initiates a swap and confirms its success. */ function swaps() { // The swap-button can be temporarily disabled following approval, & Cypress will retry clicking the disabled version. // This ensures that we don't click until the button is enabled. cy.get('#swap-button').should('not.have.attr', 'disabled') // Completes the swap. cy.get('#swap-button').click() cy.get('#confirm-swap-or-send').click() cy.get(getTestSelector('dismiss-tx-confirmation')).click() // Verifies that there is a successful swap notification. cy.contains('Swapped').should('exist') } // TODO(WEB-3299): Update tests to differentiate between permit2 vs token approval button text once UI is updated to indicate approval step. describe('Permit2', () => { // The same tokens & swap-amount combination is used for all permit2 tests. const INPUT_TOKEN = DAI const OUTPUT_TOKEN = USDC_MAINNET const TEST_BALANCE_INCREMENT = 0.01 beforeEach(() => { // Sets up a swap between INPUT_TOKEN and OUTPUT_TOKEN. cy.visit(`/swap/?inputCurrency=${INPUT_TOKEN.address}&outputCurrency=${OUTPUT_TOKEN.address}`, { ethereum: 'hardhat', }) cy.get('#swap-currency-input .token-amount-input').clear().type(TEST_BALANCE_INCREMENT.toString()) }) /** Asserts permit2 has a max approval for spend of the input token on-chain. */ function expectTokenAllowanceForPermit2ToBeMax() { // check token approval return cy .hardhat() .then(({ approval, wallet }) => approval.getTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN })) .should('deep.equal', MaxUint256) } /** Asserts the universal router has a max permit2 approval for spend of the input token on-chain. */ function expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime: number) { return cy .hardhat() .then((hardhat) => hardhat.approval.getPermit2Allowance({ owner: hardhat.wallet, token: INPUT_TOKEN })) .then((allowance) => { cy.wrap(MaxUint160.eq(allowance.amount)).should('eq', true) // Asserts that the on-chain expiration is in 30 days, within a tolerance of 40 seconds. const expected = Math.floor((approvalTime + 2_592_000_000) / 1000) cy.wrap(allowance.expiration).should('be.closeTo', expected, 40) }) } it('swaps when user has already approved token and permit2', () => { cy.hardhat() .then(({ approval, wallet }) => { approval.setTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN }) approval.setPermit2Allowance({ owner: wallet, token: INPUT_TOKEN }) }) .then(swaps) }) it('swaps after completing full permit2 approval process', () => { cy.get(APPROVE_BUTTON) .click() .then(() => { const approvalTime = Date.now() cy.get(APPROVE_BUTTON).should('have.text', 'Approval pending') // There should be a successful Approved notification. cy.contains('Approved').should('exist') swaps() expectTokenAllowanceForPermit2ToBeMax() expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime) }) }) it('swaps after handling user rejection of approvals and signatures', () => { const USER_REJECTION = { code: 4001 } cy.hardhat().then((hardhat) => { const tokenApprovalStub = cy.stub(hardhat.wallet, 'sendTransaction') tokenApprovalStub.rejects(USER_REJECTION) // reject token approval const permitApprovalStub = cy.stub(hardhat.provider, 'send') permitApprovalStub.withArgs('eth_signTypedData_v4').rejects(USER_REJECTION) // reject permit approval permitApprovalStub.callThrough() // allows non-eth_signTypedData_v4 send calls to return non-stubbed values // Clicking the approve button should trigger a token approval that will be rejected by the user (tokenApprovalStub). cy.get(APPROVE_BUTTON).click() // The swap component should prompt approval again. cy.get(APPROVE_BUTTON) .should('have.text', `Approve use of ${INPUT_TOKEN.symbol}`) .then(() => { tokenApprovalStub.restore() // allow token approval // The user is now allowing approval, but the permit2 signature will be rejected by the user (permitApprovalStub). cy.get(APPROVE_BUTTON).click() cy.get(APPROVE_BUTTON) .should('have.text', `Approve use of ${INPUT_TOKEN.symbol}`) .then(() => { permitApprovalStub.restore() // allow permit approval // The swap should now be able to proceed, as the permit2 signature will be accepted by the user. cy.get(APPROVE_BUTTON) .click() .then(() => { const approvalTime = Date.now() cy.get(APPROVE_BUTTON).should('have.text', 'Approval pending') // There should be a successful Approved notification. cy.contains('Approved').should('exist') swaps() expectTokenAllowanceForPermit2ToBeMax() expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime) }) }) }) }) }) it('swaps with existing token approval and missing permit approval', () => { cy.hardhat() .then(({ approval, wallet }) => approval.setTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN })) .then(() => { cy.get(APPROVE_BUTTON) .click() .then(() => { const approvalTime = Date.now() swaps() expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime) }) }) }) it('swaps with existing permit approval and missing token approval', () => { cy.hardhat() .then(({ approval, wallet }) => approval.setPermit2Allowance({ owner: wallet, token: INPUT_TOKEN })) .then(() => { cy.get(APPROVE_BUTTON).click() cy.get(APPROVE_BUTTON).should('have.text', 'Approval pending') // There should be a successful Approved notification. cy.contains('Approved').should('exist') swaps() expectTokenAllowanceForPermit2ToBeMax() }) }) it('prompts signature when existing permit approval is expired', () => { const expiredAllowance = { expiration: Math.floor((Date.now() - 1) / 1000) } cy.hardhat() .then(({ approval, wallet }) => { approval.setTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN }) approval.setPermit2Allowance({ owner: wallet, token: INPUT_TOKEN }, expiredAllowance) }) .then(() => { cy.get(APPROVE_BUTTON) .click() .then(() => { const approvalTime = Date.now() swaps() expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime) }) }) }) it('prompts signature when existing permit approval amount is too low', () => { const smallAllowance = { amount: 1 } cy.hardhat() .then(({ approval, wallet }) => { approval.setTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN }) approval.setPermit2Allowance({ owner: wallet, token: INPUT_TOKEN }, smallAllowance) }) .then(() => { cy.get(APPROVE_BUTTON) .click() .then(() => { const approvalTime = Date.now() swaps() expectPermit2AllowanceForUniversalRouterToBeMax(approvalTime) }) }) }) it('prompts token approval when existing approval amount is too low', () => { cy.hardhat() .then(({ approval, wallet }) => { approval.setPermit2Allowance({ owner: wallet, token: INPUT_TOKEN }) approval.setTokenAllowanceForPermit2({ owner: wallet, token: INPUT_TOKEN }, 1) }) .then(() => { cy.get(APPROVE_BUTTON).click() // There should be a successful Approved notification. cy.contains('Approved').should('exist') swaps() expectTokenAllowanceForPermit2ToBeMax() }) }) })