buidler.config.js

const { ContractFactory, ethers, Signer } = require("ethers");
const {JsonRpcProvider} = require("ethers/providers");

function createJsonRpcRequest(method, params) {
    return {
      id: nextId++,
      jsonrpc: "2.0",
      method,
      params
    };
  }
  
class EthersProviderWrapper extends JsonRpcProvider {
    constructor(provider) {
        super();
    }

    async send(method, params) {
        const result = await this.provider.send(method, params);

        // We replicate ethers' behavior.
        this.emit("debug", {
            action: "send",
            request: createJsonRpcRequest(method, params),
            response: result,
            provider: this
        });

        return result;
    }
}

extendEnvironment((env) => {
  const wrapper = new EthersProviderWrapper(env.provider);

  env.ethers = {
    provider: wrapper,
    
    getContract: async function (name) {
      const artifact = await readArtifact(env.config.paths.artifacts, name);
      const bytecode = artifact.bytecode;
      const signers = await env.ethers.signers();

      return new ethers.ContractFactory(artifact.abi, bytecode, signers[0]);
    },

    signers: async function () {
      const accounts = await env.provider.send("eth_accounts");

      return accounts.map((account) => wrapper.getSigner(account));
    }
  };
});

module.exports = {};