@typechain/hardhat

TypeChain Hardhat plugin

Zero-config TypeChain support for Hardhat

Description

Automatically generate TypeScript bindings for smartcontracts while using Hardhat.

Installation

npm install --save-dev typechain ts-generator @typechain/hardhat @typechain/ethers-v5

And add the following statement to your hardhat.config.js:

require('@typechain/hardhat')

Or, if you are using TypeScript, add this to your hardhat.config.ts:

import '@typechain/hardhat';

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 () => {
    // 1
    const signers = await ethers.signers()

    // 2
    counter = (await deployContract(<Wallet>signers[0], CounterArtifact)) as Counter
    const initialCount = await counter.getCount()

    // 3
    expect(initialCount).to.eq(0)
    expect(counter.address).to.properAddress
  })

  // 4
  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 () => {
    // 5
    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)
    })
  })
})

Examples

• starter kit
• example

Original work done by @RHLSTHRM.