Testing the safeMint function - testing

Question

I am trying to successfully write a unit test for my safeMint function below.
Here is my current test:
const assert = require("assert");
const { accounts } = require("#openzeppelin/test-environment");
const ComNFT = artifacts.require("ComNFT");
const { expect } = require("chai");
// describe('ComNFT', () => {
// let accounts;
let comNFT;
beforeEach(async () => {
accounts = await web3.eth.getAccounts();
comNFT = await ComNFT.new({ from: accounts[0] });
//comNFT = await ComNFT.at("");
// console.log(comNFT.address);
});
it('should fail when called by a non-owner account', async () => {
try {
await web3.eth.sendTransaction({
from: accounts[1], // The non-owner account
to: comNFT.address, // The contract address
data: comNFT.methods.safeMint(accounts[1], 'token URI').encodeABI() // The function call and arguments, encoded as ABI
});
assert.fail('Expected error not thrown');
} catch (error) {
assert(error.message.includes('onlyOwner'), 'Expected "onlyOwner" error message not found');
}
});
it('should be able to mint a new token', async () => {
await web3.eth.sendTransaction({
from: accounts[0], // The owner account
to: comNFT.address, // The contract address
data: comNFT.methods.safeMint(accounts[1], 'token URI').encodeABI() // The function call and arguments, encoded as ABI
});
const tokenURI = await comNFT.tokenURI(1); // Assume the token ID is 1
assert.equal(tokenURI, 'token URI');
});
function safeMint(address to, string memory uri) public onlyOwner {
uint256 tokenId = _tokenIdCounter.current();
_tokenIdCounter.increment();
_safeMint(to, tokenId);
_setTokenURI(tokenId, uri);
}
I am getting a failure message after i run npx truffle test " 1) "before each" hook for "should fail when called by a non-owner account"
0 passing (3s)
1 failing
"before each" hook for "should fail when called by a non-owner account":
TypeError: Assignment to constant variable.
at Context. (test/ComNFT.js:11:12)"
Can someone suggest a way of me successfully writing a test that calls safeMint?
The other test "itshould fail when called by a non-owner account" is also not running?
Thanks

Answer 1

safeMint function has onlyowner modifir, you should call safeMint function with the owner address that is accounts[0] (not accounts[1])