Adds TestCurrencyPermit contract supporting EIP-2612

.github/workflows/npm.yaml

@@ -19,6 +19,10 @@ on:
           - latest
           - beta
 
+permissions:
+  id-token: write  # Required for OIDC
+  contents: read
+
 jobs:
   npm-upload:
     name: NPM Package Build and Upload
@@ -29,10 +33,15 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v2
 
-      - uses: actions/setup-node@v3
+      - uses: actions/setup-node@v4
         with:
           node-version: "20"
           cache: "npm"
+          registry-url: 'https://registry.npmjs.org'
+
+      # Ensure npm 11.5.1 or later is installed
+      - name: Update npm
+        run: npm install -g npm@latest
 
       - run: npm ci
 
@@ -47,8 +56,6 @@ jobs:
 
       - run: scripts/make-npm-package.sh "${{ steps.semver.outputs.semver }}" ./build/npm-package
 
-      - run: echo "//registry.npmjs.org/:_authToken=${{ secrets.NPM_AUTOMATION_TOKEN }}" > ./build/npm-package/.npmrc
-
       - run: |
           RELEASE_TAG="${{ github.event.inputs.tag }}"
           if [ -z "$RELEASE_TAG" ]; then

contracts/TestCurrencyPermit.sol

@@ -0,0 +1,31 @@
+//SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.0;
+
+import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
+import {ERC20Permit} from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Permit.sol";
+
+contract TestCurrencyPermit is ERC20Permit {
+  uint8 internal immutable _decimals;
+
+  constructor(
+    string memory name_,
+    string memory symbol_,
+    uint256 initialSupply,
+    uint8 decimals_
+  ) ERC20(name_, symbol_) ERC20Permit(name_) {
+    _decimals = decimals_;
+    _mint(msg.sender, initialSupply);
+  }
+
+  function decimals() public view virtual override returns (uint8) {
+    return _decimals;
+  }
+
+  function mint(address recipient, uint256 amount) public virtual {
+    return _mint(recipient, amount);
+  }
+
+  function burn(address recipient, uint256 amount) public virtual {
+    return _burn(recipient, amount);
+  }
+}

js/utils.js

@@ -2,7 +2,8 @@
 const { findAll } = require("solidity-ast/utils");
 const ethers = require("ethers");
 const withArgsInternal = require("@nomicfoundation/hardhat-chai-matchers/internal/withArgs");
-const { IMPLEMENTATION_SLOT } = require("./constants");
+const helpers = require("@nomicfoundation/hardhat-network-helpers");
+const { IMPLEMENTATION_SLOT, HOUR } = require("./constants");
 
 const _E = ethers.parseEther;
 const WAD = 10n ** 18n; // 1e18
@@ -351,6 +352,69 @@ function newCaptureAny() {
 
 const captureAny = newCaptureAny();
 
+async function makeEIP2612Signature(hre, token, owner, spenderAddress, value, deadline = HOUR) {
+  // From: https://www.quicknode.com/guides/ethereum-development/transactions/how-to-use-erc20-permit-approval
+  const chainId = hre.network.config.chainId;
+  // set the domain parameters
+  const tokenAddr = await ethers.resolveAddress(token);
+  const domain = {
+    name: await token.name(),
+    version: "1",
+    chainId: chainId,
+    verifyingContract: tokenAddr,
+  };
+
+  // set the Permit type parameters
+  const types = {
+    Permit: [
+      {
+        name: "owner",
+        type: "address",
+      },
+      {
+        name: "spender",
+        type: "address",
+      },
+      {
+        name: "value",
+        type: "uint256",
+      },
+      {
+        name: "nonce",
+        type: "uint256",
+      },
+      {
+        name: "deadline",
+        type: "uint256",
+      },
+    ],
+  };
+
+  if (deadline < 1600000000) {
+    // Is a duration in seconds
+    deadline = (await helpers.time.latest()) + deadline;
+  }
+
+  const nonces = await token.nonces(owner);
+
+  // set the Permit type values
+  const ownerAddr = await ethers.resolveAddress(owner);
+  const values = {
+    owner: ownerAddr,
+    spender: spenderAddress,
+    value: value,
+    nonce: nonces,
+    deadline: deadline,
+  };
+
+  // sign the Permit type data with the deployer's private key
+  const signature = await owner.signTypedData(domain, types, values);
+
+  // split the signature into its components
+  const sig = ethers.Signature.from(signature);
+  return { sig, deadline, nonces };
+}
+
 module.exports = {
   _E,
   _A,
@@ -381,4 +445,5 @@ module.exports = {
   captureAny,
   newCaptureAny,
   AM_ROLES,
+  makeEIP2612Signature,
 };

test/test-utils-functions.js

@@ -1,7 +1,7 @@
 const hre = require("hardhat");
 const { expect } = require("chai");
 const helpers = require("@nomicfoundation/hardhat-network-helpers");
-const { _A, getRole, grantRole } = require("../js/utils");
+const { _A, getRole, grantRole, makeEIP2612Signature } = require("../js/utils");
 const { initCurrency } = require("../js/test-utils");
 
 const { ethers } = hre;
@@ -36,6 +36,23 @@ describe("Utils library tests", function () {
     return { currency };
   }
 
+  async function deployFixturePermit() {
+    // Fixture with TestCurrency (without access control)
+    const currency = await initCurrency(
+      {
+        name: "Test USDC",
+        symbol: "USDC",
+        decimals: 6,
+        initial_supply: _A(50000),
+        contractClass: "TestCurrencyPermit",
+      },
+      [anon, user1, user2, admin],
+      [_A("10000"), _A("2000"), _A("1000"), _A("20000")]
+    );
+
+    return { currency };
+  }
+
   it("Checks only MINTER_ROLE can mint (TestCurrencyAC)", async () => {
     const { currency } = await helpers.loadFixture(deployACFixture);
 
@@ -63,6 +80,31 @@ describe("Utils library tests", function () {
     expect(await currency.balanceOf(anon)).to.equal(_A(9950));
   });
 
+  it("Checks gasless spending approvals (TestCurrencyPermit)", async () => {
+    const { currency } = await helpers.loadFixture(deployFixturePermit);
+
+    expect(await currency.balanceOf(user1)).to.equal(_A(2000));
+    expect(await currency.balanceOf(user2)).to.equal(_A(1000));
+
+    const { sig, deadline } = await makeEIP2612Signature(
+      hre,
+      currency,
+      user1,
+      await ethers.resolveAddress(user2),
+      _A(200)
+    );
+    await expect(currency.permit(user1, user2, _A(200), deadline, sig.v, sig.r, sig.s))
+      .to.emit(currency, "Approval")
+      .withArgs(user1, user2, _A(200));
+
+    await expect(currency.connect(user2).transferFrom(user1, user2, _A(60)))
+      .to.emit(currency, "Transfer")
+      .withArgs(user1, user2, _A(60));
+
+    expect(await currency.balanceOf(user1)).to.equal(_A(2000 - 60));
+    expect(await currency.balanceOf(user2)).to.equal(_A(1000 + 60));
+  });
+
   it("Checks TestERC4626", async () => {
     const { currency } = await helpers.loadFixture(deployACFixture);