ProviderError: Contract creation without any data provided

Question

The error is caught during await sender.sendTransaction(txData), but the functions of my contract are working correctly.

Here's the error:

ProviderError: Contract creation without any data provided

Here's my contract:

Demo.sol

// SPDX-License-Identifier: MIT

pragma solidity 0.8.24;

contract Demo3{
    address owner;

    event Paid(address indexed _from, uint _amount, uint _timestamp);

    constructor(){
        owner = msg.sender;
    }

    receive() external payable{
        pay();
    }

   function pay() public payable {
        emit Paid(msg.sender, msg.value, block.timestamp);
   }

   modifier onlyOwner(address _to){
        require(msg.sender == owner, "You aren't owner!");
        require(_to != address(0), "inccorect address!");
        _;
   }

   function withdraw(address payable  _to) external onlyOwner(_to){
        _to.transfer(address(this).balance);
   }
}

Here's my test script:

Demo.test.js

let owner
let other_addr
let demo

beforeEach(async function () {
    [owner, other_addr] = await ethers.getSigners()

    const DemoContract = await ethers.getContractFactory("Demo3", owner)
    demo = await DemoContract.deploy()
    await demo.waitForDeployment()
})

async function sendMoney(sender) {
    const amount = 100

    const txData = {
        to: demo.address,
        value: amount
    }

    const tx = await sender.sendTransaction(txData)
    await tx.wait()
    return [tx, amount]
}

it("shound allow to send money", async function () {
    const [sendMoneyTx, amount] = await sendMoney(other_addr)

    await expect(() => sendMoneyTx)
        .to.changeEtherBalance(demo, amount);

    const timestamp = (
        await ethers.provider.getBlock(sendMoneyTx.blockNumber)
    ).timestamp

    await expect(sendMoneyTx)
        .to.emit(demo, "Paid")
        .withArgs(other_addr.address, amount, timestamp)
})  

Answer 1

You need to replace demo.address with await demo.getAddress() in your txData, like:

const txData = {
    to: await demo.getAddress(),
    value: amount
}

Also, you need to import expect from chai package, by adding the following line in the beginning of your test script:

const { expect } = require("chai");

So, your revised Demo.test.js file would be:

const { expect } = require("chai");

let owner
let other_addr
let demo

beforeEach(async function () {
    [owner, other_addr] = await ethers.getSigners()

    const DemoContract = await ethers.getContractFactory("Demo3", owner)
    demo = await DemoContract.deploy()
    await demo.waitForDeployment()
})

async function sendMoney(sender) {
    const amount = 100

    const txData = {
        to: await demo.getAddress(),
        value: amount
    }

    const tx = await sender.sendTransaction(txData)
    await tx.wait()
    return [tx, amount]
}

it("shound allow to send money", async function () {
    const [sendMoneyTx, amount] = await sendMoney(other_addr)

    await expect(() => sendMoneyTx)
        .to.changeEtherBalance(demo, amount);

    const timestamp = (
        await ethers.provider.getBlock(sendMoneyTx.blockNumber)
    ).timestamp

    await expect(sendMoneyTx)
        .to.emit(demo, "Paid")
        .withArgs(other_addr.address, amount, timestamp)
})