node --version
npx --version

.
├── artifacts
│   ├── artifacts.d.ts
│   ├── build-info
│   │   ├── solc-0_8_28-5d5e77a08f43f8366c520176a292b83d65132357.json
│   │   └── solc-0_8_28-5d5e77a08f43f8366c520176a292b83d65132357.output.json
│   └── contracts
│       └── Counter.sol
│           ├── artifacts.d.ts
│           └── Counter.json
├── cache
│   ├── build-info
│   ├── compile-cache.json
│   └── test-artifacts
│       ├── build-info
│       │   ├── solc-0_8_28-58a47ee13fa4eb204cf4c42c730b3f2707de3d94.json
│       │   └── solc-0_8_28-58a47ee13fa4eb204cf4c42c730b3f2707de3d94.output.json
│       └── contracts
│           └── Counter.t.sol
│               └── CounterTest.json
├── contracts
│   ├── Counter.sol
│   └── Counter.t.sol
├── coverage
│   ├── data
│   │   └── solidity
│   │       └── a23a0f3b-7ab8-4f87-8e19-8279db5ae7a4.json
│   └── lcov.info
├── hardhat.config.ts
├── ignition
│   ├── deployments
│   │   ├── chain-1
│   │   │   ├── artifacts
│   │   │   │   └── CounterModule#Counter.json
│   │   │   ├── build-info
│   │   │   │   └── solc-0_8_28-5d5e77a08f43f8366c520176a292b83d65132357.json
│   │   │   └── journal.jsonl
│   │   ├── chain-11155111
│   │   │   ├── artifacts
│   │   │   │   └── CounterModule#Counter.json
│   │   │   ├── build-info
│   │   │   │   └── solc-0_8_28-5d5e77a08f43f8366c520176a292b83d65132357.json
│   │   │   ├── deployed_addresses.json
│   │   │   └── journal.jsonl
│   │   └── chain-31337
│   │       ├── artifacts
│   │       │   └── CounterModule#Counter.json
│   │       ├── build-info
│   │       │   └── solc-0_8_28-5d5e77a08f43f8366c520176a292b83d65132357.json
│   │       ├── deployed_addresses.json
│   │       └── journal.jsonl
│   └── modules
│       └── Counter.ts
├── package-lock.json
├── package.json
├── README.md
├── test
│   └── Counter.ts
└── tsconfig.json

mkdir hardhat-tutorial
cd hardhat-tutorial
npx hardhat --init

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.28;

contract Counter {
  uint public x;

  event Increment(uint by);

  function inc() public {
    x += 1; 
    emit Increment(1);
  }

  function incBy(uint by) public {
    require(by > 0, "incBy: increment should be positive");
    x += by;
    emit Increment(by);
  }
}
// Random number to make this contract file unique: 185640209

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.28;

import { Counter } from "./Counter.sol";

contract CounterTest {
  Counter counter;

  function setUp() public {
    counter = new Counter();
  }

  function test_InitialValueIsZero() public view {
    require(counter.x() == 0, "x should start at 0");
  }

  function test_IncIncreasesByOne() public {
    counter.inc();
    require(counter.x() == 1, "inc should increase x by 1");
  }

  function test_IncByIncreasesByGivenAmount() public {
    counter.incBy(3);
    require(counter.x() == 3, "incBy should increase x by the given amount");
  }
}

import hardhatToolboxViemPlugin from "@nomicfoundation/hardhat-toolbox-viem";
import { defineConfig } from "hardhat/config";

export default defineConfig({
   plugins: [hardhatToolboxViemPlugin],
  solidity: {
    version: "0.8.28",
  },
});

import assert from "node:assert/strict";
import { describe, it } from "node:test";

import { network } from "hardhat";

describe("Counter", async function () {
  const { viem } = await network.connect();
  const publicClient = await viem.getPublicClient();

  it("The sum of the Increment events should match the current value", async function () {
    const counter = await viem.deployContract("Counter");
    const deploymentBlockNumber = await publicClient.getBlockNumber();

    // run a series of increments
    for (let i = 1n; i <= 10n; i++) {
      await counter.write.incBy([i]);
    }

    const events = await publicClient.getContractEvents({
      address: counter.address,
      abi: counter.abi,
      eventName: "Increment",
      fromBlock: deploymentBlockNumber,
      strict: true,
    });

    // check that the aggregated events match the current value
    let total = 0n;
    for (const event of events) {
      total += event.args.by;
    }

    assert.equal(total, await counter.read.x());
  });
});

import { buildModule } from "@nomicfoundation/hardhat-ignition/modules";

export default buildModule("CounterModule", (m) => {
  const counter = m.contract("Counter");

  m.call(counter, "incBy", [5n]);

  return { counter };
});

import hardhatToolboxViemPlugin from "@nomicfoundation/hardhat-toolbox-viem";

import { defineConfig } from "hardhat/config";
import dotenv from "dotenv";

dotenv.config();

export default defineConfig({
  plugins: [hardhatToolboxViemPlugin],
  solidity: {
    version: "0.8.28",
  },
  networks: {
    sepolia: {
      type: "http",
      url: process.env.SEPOLIA_RPC_URL || "",
      accounts: process.env.SEPOLIA_PRIVATE_KEY ? [process.env.SEPOLIA_PRIVATE_KEY] : [],
    },
  },
});