Migrate contract tests to strict TypeScript

.eslintignore

@@ -1 +1,2 @@
 export/
+typechain/

.eslintrc

@@ -10,5 +10,22 @@
   },
   "rules": {
     "new-cap": "off"
-  }
+  },
+  "overrides": [
+    {
+      "files": ["*.ts"],
+      "parser": "@typescript-eslint/parser",
+      "parserOptions": {
+        "project": "./tsconfig.json"
+      },
+      "extends": ["plugin:@typescript-eslint/recommended"],
+      "rules": {
+        "@typescript-eslint/no-floating-promises": [
+          "error",
+          { "ignoreVoid": false }
+        ],
+        "@typescript-eslint/no-misused-promises": "error"
+      }
+    }
+  ]
 }

.prettierignore

@@ -6,3 +6,4 @@ deployments/
 docgen-templates/
 export/
 export.json
+typechain/

README.adoc

@@ -29,16 +29,29 @@ Once packages are installed, you can build the smart contracts using:
 ```
 yarn build
 ```
-Compiled contracts will land in the `build` directory.
+Compiled contracts will land in the `build` directory. The build also generates
+ethers v5 contract types in `typechain`; these files should not be edited or
+committed.
 
 === Test contracts
 
-There are multiple test scenarios living in the `test` directory.
+The tests in the `test` directory use TypeScript and generated contract types.
 You can run them by doing:
 ```
 yarn test
 ```
 
+To regenerate contract types and check the tests, deployment scripts, tasks, and
+Hardhat configuration with strict TypeScript settings, run:
+```
+yarn typecheck
+```
+
+`yarn format` runs type checking, linting, and formatting checks in CI. Linting
+also rejects unhandled promises, so asynchronous setup and contract calls must
+be awaited or returned. The package continues to export JavaScript deployment
+scripts; tests and generated contract types are not published.
+
 === Deploy contracts
 
 To deploy all contracts on the given network, please run:

deploy/02_mint_t.ts

@@ -8,7 +8,7 @@ const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
   const { execute, read, log } = deployments
   const { to1e18, from1e18 } = helpers.number
 
-  const T = await deployments.get("T")
+  await deployments.get("T")
 
   const totalSupply: BigNumber = await read("T", "totalSupply")
 

deploy/07_deploy_token_staking.ts

@@ -2,6 +2,7 @@ import { HardhatRuntimeEnvironment } from "hardhat/types"
 import { DeployFunction } from "hardhat-deploy/types"
 
 import { ethers, upgrades } from "hardhat"
+import * as fs from "fs"
 
 const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
   const { getNamedAccounts, deployments } = hre
@@ -11,7 +12,7 @@ const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
   const T = await deployments.get("T")
 
   const tokenStakingConstructorArgs = [T.address]
-  const tokenStakingInitializerArgs = []
+  const tokenStakingInitializerArgs: [] = []
 
   // TODO: Consider upgradable deployment also for sepolia.
   let tokenStakingAddress
@@ -29,22 +30,18 @@ const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
     log(`Deployed TokenStaking with TransparentProxy at ${tokenStakingAddress}`)
 
     const implementationInterface = tokenStaking.interface
-    let jsonAbi = implementationInterface.format(ethers.utils.FormatTypes.json)
+    const jsonAbi = implementationInterface.format(
+      ethers.utils.FormatTypes.json
+    )
 
     const tokenStakingDeployment = {
       address: tokenStakingAddress,
       abi: JSON.parse(jsonAbi as string),
     }
-    const fs = require("fs")
     fs.writeFileSync(
       "TokenStaking.json",
       JSON.stringify(tokenStakingDeployment, null, 2),
-      "utf8",
-      function (err) {
-        if (err) {
-          console.log(err)
-        }
-      }
+      "utf8"
     )
     log(`Saved TokenStaking address and ABI in TokenStaking.json`)
   } else {

deploy/30_deploy_tokenholder_timelock.ts

@@ -10,7 +10,7 @@ const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
   const { getNamedAccounts, deployments } = hre
   const { deployer } = await getNamedAccounts()
 
-  const proposers = []
+  const proposers: string[] = []
   const executors = [ethers.constants.AddressZero]
   const minDelay = 172800 // 2 days in seconds (2 * 24 * 60 * 60)
 

deploy/31_deploy_tokenholder_governor.ts

@@ -6,7 +6,7 @@ const func: DeployFunction = async function (hre: HardhatRuntimeEnvironment) {
   const { deployer, thresholdCouncil } = await getNamedAccounts()
 
   // TODO: fail if thresholdCouncil is undefined on mainnet
-  let vetoer = thresholdCouncil ?? deployer
+  const vetoer = thresholdCouncil ?? deployer
 
   const T = await deployments.get("T")
   const TokenStaking = await deployments.get("TokenStaking")

hardhat.config.ts

@@ -6,6 +6,7 @@ import "@nomiclabs/hardhat-ethers"
 import "@nomicfoundation/hardhat-chai-matchers"
 import "@openzeppelin/hardhat-upgrades"
 import "@nomicfoundation/hardhat-verify"
+import "@typechain/hardhat"
 import { Tenderly } from "@tenderly/hardhat-tenderly/dist/Tenderly"
 import "@tenderly/hardhat-tenderly/dist/type-extensions"
 
@@ -43,6 +44,11 @@ const config: HardhatUserConfig = {
   paths: {
     artifacts: "./build",
   },
+  typechain: {
+    outDir: "typechain",
+    target: "ethers-v5",
+    alwaysGenerateOverloads: true,
+  },
   networks: {
     hardhat: {
       forking: {
@@ -68,7 +74,7 @@ const config: HardhatUserConfig = {
       accounts: process.env.CONTRACT_OWNER_ACCOUNT_PRIVATE_KEY
         ? [
             process.env.CONTRACT_OWNER_ACCOUNT_PRIVATE_KEY,
-            process.env.KEEP_CONTRACT_OWNER_ACCOUNT_PRIVATE_KEY, // TODO: verify if we have different owner here or can we remove this
+            process.env.KEEP_CONTRACT_OWNER_ACCOUNT_PRIVATE_KEY!, // TODO: verify if we have different owner here or can we remove this
           ]
         : undefined,
       tags: ["tenderly"],

package.json

@@ -21,14 +21,14 @@
     "format:fix": "npm run lint:fix && prettier --write .",
     "lint": "npm run typecheck && npm run lint:js && npm run lint:sol",
     "lint:fix": "npm run lint:fix:js && npm run lint:fix:sol",
-    "lint:fix:js": "eslint . --fix",
+    "lint:fix:js": "eslint . --ext .js,.ts --fix",
     "lint:fix:sol": "solhint 'contracts/**/*.sol' --fix",
-    "lint:js": "eslint . ",
+    "lint:js": "eslint . --ext .js,.ts",
     "lint:sol": "solhint 'contracts/**/*.sol'",
     "test": "hardhat test",
-    "test:system": "NODE_ENV=system-test hardhat test ./test/system/*.test.js",
-    "typecheck": "tsc --noEmit -p tsconfig.json",
-    "prepack": "tsc -p tsconfig.export.json && hardhat export-artifacts export/artifacts",
+    "test:system": "NODE_ENV=system-test hardhat test ./test/system/*.test.ts",
+    "typecheck": "hardhat typechain && tsc --noEmit -p tsconfig.json",
+    "prepack": "hardhat typechain && tsc -p tsconfig.export.json && hardhat export-artifacts export/artifacts",
     "prepublishOnly": "rm -rf artifacts/ && hardhat export-deployment-artifacts --network $npm_config_network"
   },
   "devDependencies": {
@@ -39,11 +39,17 @@
     "@nomiclabs/hardhat-ethers": "^2.2.3",
     "@openzeppelin/hardhat-upgrades": "^1.28.0",
     "@tenderly/hardhat-tenderly": "1.8.0",
+    "@typechain/ethers-v5": "10.2.1",
+    "@typechain/hardhat": "6.1.6",
     "@types/chai": "^4.3.20",
+    "@types/chai-as-promised": "7.1.8",
+    "@types/debug": "4.1.12",
     "@types/mocha": "^10.0.10",
     "@types/node": "^22.20.1",
+    "@typescript-eslint/eslint-plugin": "8.70.0",
+    "@typescript-eslint/parser": "8.70.0",
     "chai": "^4.5.0",
-    "eslint": "^7.32.0",
+    "eslint": "8.57.1",
     "eslint-config-keep": "github:keep-network/eslint-config-keep#0c27ade",
     "ethers": "^5.8.0",
     "hardhat": "^2.29.0",
@@ -57,6 +63,7 @@
     "solhint-config-keep": "github:keep-network/solhint-config-keep",
     "solidity-docgen": "^0.6.0-beta.36",
     "ts-node": "^10.9.2",
+    "typechain": "8.3.2",
     "typescript": "^5.9.3"
   },
   "dependencies": {

test/governance/GovernorParameters.test.js → test/governance/GovernorParameters.test.ts

@@ -1,8 +1,13 @@
-const { expect } = require("chai")
+import type { ContractTransaction } from "ethers"
+import type { TestGovernorParameters } from "../../typechain"
+import type { SignerWithAddress } from "@nomiclabs/hardhat-ethers/signers"
+import { ethers } from "hardhat"
+import { expect } from "chai"
 
 describe("ParametersGovernor", () => {
-  let executor
-  let other
+  let tGov: TestGovernorParameters
+  let executor: SignerWithAddress
+  let other: SignerWithAddress
 
   beforeEach(async () => {
     ;[executor, other] = await ethers.getSigners()
@@ -37,10 +42,10 @@ describe("ParametersGovernor", () => {
   })
 
   describe("parameters are updated", () => {
-    let tx1
-    let tx2
-    let tx3
-    let tx4
+    let tx1: ContractTransaction
+    let tx2: ContractTransaction
+    let tx3: ContractTransaction
+    let tx4: ContractTransaction
     beforeEach(async () => {
       tx1 = await tGov.connect(executor).updateQuorumNumerator(100)
       tx2 = await tGov.connect(executor).updateProposalThresholdNumerator(200)

test/governance/ProxyAdminWithDeputy.test.js → test/governance/ProxyAdminWithDeputy.test.ts

@@ -1,24 +1,33 @@
-const { expect } = require("chai")
-
-const { upgrades } = require("hardhat")
+import type {
+  ProxyAdmin,
+  ProxyAdminWithDeputy,
+  SimpleStorage,
+  SimpleStorage__factory as SimpleStorageFactory,
+  TestTokenholderGovernorStubV2,
+} from "../../typechain"
+import type { SignerWithAddress } from "@nomiclabs/hardhat-ethers/signers"
+import { ethers, upgrades } from "hardhat"
+import { expect } from "chai"
 
 describe("ProxyAdminWithDeputy", () => {
-  let deployer
-  let deputy
-  let timelock
-  let adminWithDeputy
-
-  let SimpleStorage
+  let tGov: TestTokenholderGovernorStubV2
+  let storage: SimpleStorage
+  let deployer: SignerWithAddress
+  let deputy: SignerWithAddress
+  let timelock: SignerWithAddress
+  let adminWithDeputy: ProxyAdminWithDeputy
+
+  let SimpleStorage: SimpleStorageFactory
   const initialState = 42
 
   beforeEach(async () => {
     ;[deployer, deputy, timelock] = await ethers.getSigners()
     SimpleStorage = await ethers.getContractFactory("SimpleStorage")
     const initializerArgs = [initialState] // stored value in proxy state
-    storage = await upgrades.deployProxy(SimpleStorage, initializerArgs, {
+    storage = (await upgrades.deployProxy(SimpleStorage, initializerArgs, {
       kind: "transparent",
       constructorArgs: [1], // implementation version 1
-    })
+    })) as SimpleStorage
     await storage.deployed()
 
     const GovernorStub = await ethers.getContractFactory(
@@ -38,18 +47,21 @@ describe("ProxyAdminWithDeputy", () => {
   })
 
   describe("Plain Upgrades deployment - No ProxyAdminWithDeputy", () => {
-    let newImplementationAddress
-    let adminInstance
+    let newImplementationAddress: string
+    let adminInstance: ProxyAdmin
 
     beforeEach(async () => {
-      newImplementationAddress = await upgrades.prepareUpgrade(
+      const implementation = await upgrades.prepareUpgrade(
         storage.address,
         SimpleStorage,
         {
           constructorArgs: [2],
         }
       )
-      adminInstance = await upgrades.admin.getInstance()
+      if (typeof implementation !== "string")
+        throw new Error("Expected implementation address")
+      newImplementationAddress = implementation
+      adminInstance = (await upgrades.admin.getInstance()) as ProxyAdmin
     })
 
     it("ProxyAdmin is the admin for the UpgradeableProxy", async () => {
@@ -98,16 +110,19 @@ describe("ProxyAdminWithDeputy", () => {
     })
 
     describe("Upgrades procedure with ProxyAdminWithDeputy", () => {
-      let newImplementationAddress
+      let newImplementationAddress: string
 
       beforeEach(async () => {
-        newImplementationAddress = await upgrades.prepareUpgrade(
+        const implementation = await upgrades.prepareUpgrade(
           storage.address,
           SimpleStorage,
           {
             constructorArgs: [2],
           }
         )
+        if (typeof implementation !== "string")
+          throw new Error("Expected implementation address")
+        newImplementationAddress = implementation
       })
 
       it("before upgrade, implementation version is 1", async () => {