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TypeError: Cannot read properties of undefined (reading ‘equal’) [closed]

I have created 2 TESTS —

In 2nd TEST, I have enclosed owner, addr1, addr2 in [] as per the Official Hardhat Documentation, like this const [owner,addr1,addr2] = await ethers.getSigners();, But the problem is when I use [] bracket, it shows me the error TypeError: Cannot read properties of undefined (reading 'equal') and the test also failed,

Here is the Code —>

const { expect } = require('chai');
// const { ethers } = require('hardhat');


describe('Token contract', function () {
    //1st TEST

    it('Deployment should assign the total supply of the tokens to the owner', async function () {
        const [owner] = await ethers.getSigners();
        

        const Token = await ethers.getContractFactory('Token');

        const hardhatToken = await Token.deploy();

        const ownerBalance = await hardhatToken.balanceOf(owner.address);
        
        expect(await hardhatToken.totalSupply()).to.equal(ownerBalance);
    });

    //2nd TEST

    it('Should Transfer Tokens between accounts', async function () {
        
        const [owner,addr1,addr2] = await ethers.getSigners();
        

        const Token = await ethers.getContractFactory('Token');

        const hardhatToken = await Token.deploy();

        //Transfer 10 tokens from Owner to addr1
        await hardhatToken.transfer(addr1.address,10);
        expect(await hardhatToken.balanceOf(addr1.address).to.equal(10));

        //Transfer 5 tokens from addr1 to addr2
        await hardhatToken.connect(addr1).transfer(addr2.address,5);
        expect(await hardhatToken.balanceOf(addr2.address).to.equal(5))
    });
});

But if U see in the 1st TEST, I haven’t used [], for owner, so the test passed. Below is the Official Hardhat documentation if U want to check the code —>

https://hardhat.org/tutorial/testing-contracts.html

Please help me to solve this Problem Thanks

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Answer

You didn’t close the parenthesis around the expect calls in the second test correctly. You’re accessing .to on the number returned by .balanceOf.

Replace with:

expect(await hardhatToken.balanceOf(addr1.address)).to.equal(10);
// ...
expect(await hardhatToken.balanceOf(addr2.address)).to.equal(5);
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