hardhat-typechain
Zero-config Typechain support
Updated for Hardhat!
Now supports Ethers v5 and Truffle v5!
Updated for TypeChain v3!
Add Typechain tasks to your hardhat project!
What
TypeChain gives you Typescript bindings for your smart contracts. Now, your tests and frontend code can be typesafe and magically autocomplete smart contract function names!
Installation
npm i hardhat-typechain typechain ts-generator
npm i @typechain/ethers-v5 @typechain/truffle-v5 @typechain/web3-v1
And add the following statement to your hardhat.config.js
:
require("hardhat-typechain");
Or, if you are using TypeScript, add this to your hardhat.config.ts
:
import "hardhat-typechain";
Zero Config Usage
Run the compile task as normal, and Typechain artifacts will automatically be generated in a root directory called typechain
. Further configuration options are detailed below.
Tasks
This plugin overrides the compile task and automatically generates new Typechain artifacts on each compilation.
There is an optional flag --no-typechain
which can be passed in to skip Typechain compilation.
This plugin adds the typechain task to hardhat:
Generate Typechain typings for compiled contracts
Configuration
This plugin extends the hardhatConfig
optional typechain
object. The object contains two fields, outDir
and target
. outDir
is the output directory of the artifacts that TypeChain creates (defaults to typechain
). target
is one of the targets specified by the TypeChain docs (defaults to ethers
).
This is an example of how to set it:
module.exports = {
typechain: {
outDir: "src/types",
target: "ethers-v5",
},
};
Usage
npx hardhat compile
- Compiles and generates Typescript typings for your contracts.
Example Waffle + Ethers test that uses typedefs for contracts:
import { ethers, waffle } from "@nomiclabs/hardhat";
import chai from "chai";
import { Wallet } from "ethers";
import CounterArtifact from "../artifacts/Counter.json";
import { Counter } from "../typechain/Counter";
const { deployContract } = waffle;
const { expect } = chai;
describe("Counter", () => {
let counter: Counter;
beforeEach(async () => {
const signers = await ethers.signers();
counter = (await deployContract(
<Wallet>signers[0],
CounterArtifact
)) as Counter;
const initialCount = await counter.getCount();
expect(initialCount).to.eq(0);
expect(counter.address).to.properAddress;
});
describe("count up", async () => {
it("should count up", async () => {
await counter.countUp();
let count = await counter.getCount();
expect(count).to.eq(1);
});
});
describe("count down", async () => {
it("should fail", async () => {
await counter.countDown();
});
it("should count down", async () => {
await counter.countUp();
await counter.countDown();
const count = await counter.getCount();
expect(count).to.eq(0);
});
});
});
See this starter kit for a full example!