feat: create a mocha/ethers template project

As part of the Alpha prep this adds a mocha/ethers template project that
tries to recreate the functionality (we are currently able to support)
of the v2 Ethers typescript project in v3.

It pulls in the `v-next` versions of the mocha test runner, the
`hardhat-test-helpers` and `hardhat-ethers`.

It adds a the `Lock.sol` and `Lock.ts` test file. The test file has been
modified to allow for running the tests while we still have rough edges.

Specifically the rough edges are:
- we need new patterns for sharing `connection` among tests (I added a
  `beforeEach`)
- we don't have chai matchers so I added `chai-as-promised` and adapted
  the tests ... crudely.

.changeset/pre.json

@@ -35,6 +35,7 @@
     "template-empty-javascript": "0.0.1",
     "template-empty-typescript": "0.0.1",
     "template-javascript-with-examples": "0.0.1",
+    "template-mocha-ethers": "0.0.1",
     "template-typescript-with-examples": "0.0.1"
   },
   "changesets": [

v-next/hardhat/templates/mocha-ethers/.gitignore

@@ -0,0 +1,14 @@
+# Node modules
+/node_modules
+
+# Compilation output
+/dist
+
+# pnpm deploy output
+/bundle
+
+# Hardhat Build Artifacts
+/artifacts
+
+# Hardhat compilation (v2) support directory
+/cache

v-next/hardhat/templates/mocha-ethers/README.md

@@ -0,0 +1,20 @@
+# A TypeScript Hardhat project using Mocha and Ethers
+
+> WARNING: This demonstration project is still in development. It is part of the Hardhat v3 upgrade. It is not for production use.
+
+> NOTE: There are several plugins from the Hardhat toolbox that have not been ported to Hardhat v3 yet. In testing terms, the biggest ommision is `hardhat-chai-matchers`.
+
+This project demonstrates basic Hardhat usecases within a TypeScript project. It comes with a minimal Hardhat configuration file and a test.
+
+For integration testing it uses the Mocha test runner and the Ethers.js library for interacting with Ethereum nodes.
+
+Try running the following commands to see Hardhat in action:
+
+```shell
+# Setup a running Hardhat v2 node in another terminal: `npx hardhat node`
+
+# The test command does not currently trigger the compilation step
+npx hardhat3 compile
+# Run the mocha integration test suite
+npx hardhat3 test
+```

v-next/hardhat/templates/mocha-ethers/contracts/Lock.sol

@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.24;
+
+// Uncomment this line to use console.log
+// import "hardhat/console.sol";
+
+contract Lock {
+    uint public unlockTime;
+    address payable public owner;
+
+    event Withdrawal(uint amount, uint when);
+
+    constructor(uint _unlockTime) payable {
+        require(
+            block.timestamp < _unlockTime,
+            "Unlock time should be in the future"
+        );
+
+        unlockTime = _unlockTime;
+        owner = payable(msg.sender);
+    }
+
+    function withdraw() public {
+        // Uncomment this line, and the import of "hardhat/console.sol", to print a log in your terminal
+        // console.log("Unlock time is %o and block timestamp is %o", unlockTime, block.timestamp);
+
+        require(block.timestamp >= unlockTime, "You can't withdraw yet");
+        require(msg.sender == owner, "You aren't the owner");
+
+        emit Withdrawal(address(this).balance, block.timestamp);
+
+        owner.transfer(address(this).balance);
+    }
+}

v-next/hardhat/templates/mocha-ethers/hardhat.config.ts

@@ -0,0 +1,12 @@
+import type { HardhatUserConfig } from "@ignored/hardhat-vnext/types/config";
+
+import HardhatMochaTestRunner from "@ignored/hardhat-vnext-mocha-test-runner";
+import HardhatEthers from "@ignored/hardhat-vnext-ethers";
+import HardhatNetworkHelpers from "@ignored/hardhat-vnext-network-helpers";
+
+const config: HardhatUserConfig = {
+  plugins: [HardhatMochaTestRunner, HardhatEthers, HardhatNetworkHelpers],
+  solidity: "0.8.24",
+};
+
+export default config;

v-next/hardhat/templates/mocha-ethers/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "template-mocha-ethers",
+  "private": true,
+  "version": "0.0.1",
+  "description": "A Typescript Hardhat project using Mocha and Ethers.js",
+  "type": "module",
+  "devDependencies": {
+    "@ignored/hardhat-vnext": "workspace:^3.0.0-next.5",
+    "@ignored/hardhat-vnext-ethers": "workspace:^3.0.0-next.1",
+    "@ignored/hardhat-vnext-mocha-test-runner": "workspace:^3.0.0-next.1",
+    "@ignored/hardhat-vnext-network-helpers": "workspace:^3.0.0-next.1",
+    "@types/chai": "^4.2.0",
+    "@types/chai-as-promised": "^8.0.1",
+    "@types/mocha": ">=9.1.0",
+    "chai": "^4.4.1",
+    "chai-as-promised": "^8.0.0",
+    "mocha": "^10.0.0",
+    "typescript": "~5.5.0"
+  }
+}