@unipeer/buidler-typechain

buidler-typechain

Better integration with buidler builtin tasks!

Add Typechain tasks to your Buidler 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 @unipeer/buidler-typechain typechain ts-generator

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

usePlugin("@unipeer/buidler-typechain");

Tasks

This plugin adds the typechain task to Buidler:

Generate Typechain typings for compiled contracts

Configuration

This plugin extends the BuidlerConfig 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).

You can also configure this plugin to automatically run after ever compile or test command by setting the onTest or onCompile fields to true. onTest is by default set to true and is recommended to avoid any frustrations in case where you forget to re-generate types after updating a contract and your tests are out of sync with your contract code.

This is an example of how to set it:

module.exports = {
  typechain: {
    outDir: "src/types",
    target: "ethers-v5",
    onTest: true,
    onCompile: false
  },
};

Usage

npx buidler typechain - Compiles and generates Typescript typings for your contracts.

Example Waffle + Ethers test that uses typedefs for contracts:

import { ethers } from "@nomiclabs/buidler";
import chai from "chai";
import { Wallet } from "ethers";
import { deployContract, solidity } from "ethereum-waffle";

import CounterArtifact from "../artifacts/Counter.json";
import { Counter } from "../typechain/Counter";

chai.use(solidity);
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);
    });
  });
});

See this starter kit for a full example!

TypeScript support

You need to add this to your tsconfig.json's files array: "node_modules/@unipeer/buidler-typechain/src/type-extensions.d.ts"