web3-testing

• The task is unrelated to web3 smart contract testing
• You need a different domain or tool outside this scope

• Clarify goals, constraints, and required inputs.
• Apply relevant best practices and validate outcomes.
• Provide actionable steps and verification.
• If detailed examples are required, open resources/implementation-playbook.md.

• Writing unit tests for smart contracts
• Setting up integration test suites
• Performing gas optimization testing
• Fuzzing for edge cases
• Forking mainnet for realistic testing
• Automating test coverage reporting
• Verifying contracts on Etherscan

```javascript

// hardhat.config.js

require("@nomicfoundation/hardhat-toolbox");

require("@nomiclabs/hardhat-etherscan");

require("hardhat-gas-reporter");

require("solidity-coverage");

module.exports = {

solidity: {

version: "0.8.19",

settings: {

optimizer: {

enabled: true,

runs: 200,

},

},

},

networks: {

hardhat: {

forking: {

url: process.env.MAINNET_RPC_URL,

blockNumber: 15000000,

},

},

goerli: {

url: process.env.GOERLI_RPC_URL,

accounts: [process.env.PRIVATE_KEY],

},

},

gasReporter: {

enabled: true,

currency: "USD",

coinmarketcap: process.env.COINMARKETCAP_API_KEY,

},

etherscan: {

apiKey: process.env.ETHERSCAN_API_KEY,

},

};

```

```javascript

const { expect } = require("chai");

const { ethers } = require("hardhat");

const {

loadFixture,

time,

} = require("@nomicfoundation/hardhat-network-helpers");

describe("Token Contract", function () {

// Fixture for test setup

async function deployTokenFixture() {

const [owner, addr1, addr2] = await ethers.getSigners();

const Token = await ethers.getContractFactory("Token");

const token = await Token.deploy();

return { token, owner, addr1, addr2 };

}

describe("Deployment", function () {

it("Should set the right owner", async function () {

const { token, owner } = await loadFixture(deployTokenFixture);

expect(await token.owner()).to.equal(owner.address);

});

it("Should assign total supply to owner", async function () {

const { token, owner } = await loadFixture(deployTokenFixture);

const ownerBalance = await token.balanceOf(owner.address);

expect(await token.totalSupply()).to.equal(ownerBalance);

});

});

describe("Transactions", function () {

it("Should transfer tokens between accounts", async function () {

const { token, owner, addr1 } = await loadFixture(deployTokenFixture);

await expect(token.transfer(addr1.address, 50)).to.changeTokenBalances(

token,

[owner, addr1],

[-50, 50],

);

});

it("Should fail if sender doesn't have enough tokens", async function () {

const { token, addr1 } = await loadFixture(deployTokenFixture);

const initialBalance = await token.balanceOf(addr1.address);

await expect(

token.connect(addr1).transfer(owner.address, 1),

).to.be.revertedWith("Insufficient balance");

});

it("Should emit Transfer event", async function () {

const { token, owner, addr1 } = await loadFixture(deployTokenFixture);

await expect(token.transfer(addr1.address, 50))

.to.emit(token, "Transfer")

.withArgs(owner.address, addr1.address, 50);

});

});

describe("Time-based tests", function () {

it("Should handle time-locked operations", async function () {

const { token } = await loadFixture(deployTokenFixture);

// Increase time by 1 day

await time.increase(86400);

// Test time-dependent functionality

});

});

describe("Gas optimization", function () {

it("Should use gas efficiently", async function () {

const { token } = await loadFixture(deployTokenFixture);

const tx = await token.transfer(addr1.address, 100);

const receipt = await tx.wait();

expect(receipt.gasUsed).to.be.lessThan(50000);

});

});

});

```

```solidity

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "forge-std/Test.sol";

import "../src/Token.sol";

contract TokenTest is Test {

Token token;

address owner = address(1);

address user1 = address(2);

address user2 = address(3);

function setUp() public {

vm.prank(owner);

token = new Token();

}

function testInitialSupply() public {

assertEq(token.totalSupply(), 1000000 10*18);

}

function testTransfer() public {

vm.prank(owner);

token.transfer(user1, 100);

assertEq(token.balanceOf(user1), 100);

assertEq(token.balanceOf(owner), token.totalSupply() - 100);

}

function testFailTransferInsufficientBalance() public {

vm.prank(user1);

token.transfer(user2, 100); // Should fail

}

function testCannotTransferToZeroAddress() public {

vm.prank(owner);

vm.expectRevert("Invalid recipient");

token.transfer(address(0), 100);

}

// Fuzzing test

function testFuzzTransfer(uint256 amount) public {

vm.assume(amount > 0 && amount <= token.totalSupply());

vm.prank(owner);

token.transfer(user1, amount);

assertEq(token.balanceOf(user1), amount);

}

// Test with cheatcodes

function testDealAndPrank() public {

// Give ETH to address

vm.deal(user1, 10 ether);

// Impersonate address

vm.prank(user1);

// Test functionality

assertEq(user1.balance, 10 ether);

}

// Mainnet fork test

function testForkMainnet() public {

vm.createSelectFork("https://eth-mainnet.alchemyapi.io/v2/...");

// Interact with mainnet contracts

address dai = 0x6B175474E89094C44Da98b954EedeAC495271d0F;

assertEq(IERC20(dai).symbol(), "DAI");

}

}

```

Snapshot and Revert

```javascript

describe("Complex State Changes", function () {

let snapshotId;

beforeEach(async function () {

snapshotId = await network.provider.send("evm_snapshot");

});

afterEach(async function () {

await network.provider.send("evm_revert", [snapshotId]);

});

it("Test 1", async function () {

// Make state changes

});

it("Test 2", async function () {

// State reverted, clean slate

});

});

```

Mainnet Forking

```javascript

describe("Mainnet Fork Tests", function () {

let uniswapRouter, dai, usdc;

before(async function () {

await network.provider.request({

method: "hardhat_reset",

params: [

{

forking: {

jsonRpcUrl: process.env.MAINNET_RPC_URL,

blockNumber: 15000000,

},

},

],

});

// Connect to existing mainnet contracts

uniswapRouter = await ethers.getContractAt(

"IUniswapV2Router",

"0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D",

);

dai = await ethers.getContractAt(

"IERC20",

"0x6B175474E89094C44Da98b954EedeAC495271d0F",

);

});

it("Should swap on Uniswap", async function () {

// Test with real Uniswap contracts

});

});

```

Impersonating Accounts

```javascript

it("Should impersonate whale account", async function () {

const whaleAddress = "0x...";

await network.provider.request({

method: "hardhat_impersonateAccount",

params: [whaleAddress],

});

const whale = await ethers.getSigner(whaleAddress);

// Use whale's tokens

await dai

.connect(whale)

.transfer(addr1.address, ethers.utils.parseEther("1000"));

});

```

```javascript

const { expect } = require("chai");

describe("Gas Optimization", function () {

it("Compare gas usage between implementations", async function () {

const Implementation1 =

await ethers.getContractFactory("OptimizedContract");

const Implementation2 = await ethers.getContractFactory(

"UnoptimizedContract",

);

const contract1 = await Implementation1.deploy();

const contract2 = await Implementation2.deploy();

const tx1 = await contract1.doSomething();

const receipt1 = await tx1.wait();

const tx2 = await contract2.doSomething();

const receipt2 = await tx2.wait();

console.log("Optimized gas:", receipt1.gasUsed.toString());

console.log("Unoptimized gas:", receipt2.gasUsed.toString());

expect(receipt1.gasUsed).to.be.lessThan(receipt2.gasUsed);

});

});

```

```bash

# Generate coverage report

npx hardhat coverage

# Output shows:

# File | % Stmts | % Branch | % Funcs | % Lines |

# -------------------|---------|----------|---------|---------|

# contracts/Token.sol | 100 | 90 | 100 | 95 |

```

```javascript

// Verify on Etherscan

await hre.run("verify:verify", {

address: contractAddress,

constructorArguments: [arg1, arg2],

});

```

```bash

# Or via CLI

npx hardhat verify --network mainnet CONTRACT_ADDRESS "Constructor arg1" "arg2"

```

```yaml

# .github/workflows/test.yml

name: Tests

on: [push, pull_request]

jobs:

test:

runs-on: ubuntu-latest

steps:

- uses: actions/checkout@v2

- uses: actions/setup-node@v2

with:

node-version: "16"

- run: npm install

- run: npx hardhat compile

- run: npx hardhat test

- run: npx hardhat coverage

- name: Upload coverage to Codecov

uses: codecov/codecov-action@v2

```

• references/hardhat-setup.md: Hardhat configuration guide
• references/foundry-setup.md: Foundry testing framework
• references/test-patterns.md: Testing best practices
• references/mainnet-forking.md: Fork testing strategies
• references/contract-verification.md: Etherscan verification
• assets/hardhat-config.js: Complete Hardhat configuration
• assets/test-suite.js: Comprehensive test examples
• assets/foundry.toml: Foundry configuration
• scripts/test-contract.sh: Automated testing script

1. Test Coverage: Aim for >90% coverage
2. Edge Cases: Test boundary conditions
3. Gas Limits: Verify functions don't hit block gas limit
4. Reentrancy: Test for reentrancy vulnerabilities
5. Access Control: Test unauthorized access attempts
6. Events: Verify event emissions
7. Fixtures: Use fixtures to avoid code duplication
8. Mainnet Fork: Test with real contracts
9. Fuzzing: Use property-based testing
10. CI/CD: Automate testing on every commit