Error while following examples while writing test. Already used -> await expect(fundMe.fund()).to.be.revertedWith("you need to spend more ETH!" ); BUT error still says fails if you don't send enough ETH.

[Glow-in-the-dark]

Followed the tutorial here : https://youtu.be/gyMwXuJrbJQ?t=40731

However, when I run the test, i have errors:

This is my FundMe.test.js script.

const { deployments, ethers } = require("hardhat");
const { assert, expect } = require("chai");

describe("FundMe", async function () {
  let fundMe;
  let deployer;
  let mockV3Aggregator;
  //deploy FundMe conctract first before we test.
  // using Hardhat-deploy
  beforeEach(async function () {
    // const accounts = await ethers.getSigners(); // this line will return the "accounts: [Private_key]" of your network.
    // const accountZero = accounts[0];
    deployer = (await getNamedAccounts()).deployer;
    await deployments.fixture(["all"]);
    (fundMe = await ethers.getContract("FundMe")), deployer; //get the most recent deployed contract of "FundMe"
    mockV3Aggregator = await ethers.getContract("MockV3Aggregator", deployer);
  });

  describe("constructor", async function () {
    //describe
    it("sets the aggregator address correctly", async function () {
      const response = await fundMe.priceFeed();
      assert.equal(response, mockV3Aggregator.address);
    });
  });

  describe("fund", async function () {
    it("Fails if you don't send enough ETH", async function () {
      // by using expect().to.be.revertedWith , we can expect things to be failed, else if we use asset, athought it failed correctly, it will break the test.
      await expect(fundMe.fund()).to.be.revertedWith(
        "you neeed to spend more ETH!"
      );
    });
  });
});

[pratokko]

Hello that means that in your contract you did set the error to didn't send enough so to fix the issue you need to go to your contract and change the error to you need to spend more ETH like this

    function fund() public payable {
        require(
            msg.value.getConversionRate(s_priceFeed) >= MINIMUM_USD,
            "You need to spend more ETH!"
        );

[Glow-in-the-dark]

mmm it seems to be inside already tho, is it not ? or did i miss something ? @pratokko :

    function fund() public payable {
    // want to be able to set a minimum fund amt in USD
    // 1. How to we send ETH to this address
    require ( msg.value.getConversionRate(priceFeed) >= MINIMUM_USD, "didn't send enough"); // means if they send, it will have to me more than 1ETH.data, else it will revert.
    funders.push(msg.sender);
    addressToAmountFunded[msg.sender] += msg.value;
    }

[pratokko]

yes you have to change the

 "didn't send enough"

you have in your code with

 "You need to spend more ETH!"

keep in mind that what you have in your test should match what you have in your contract for the reverts to match

so replace this line

 require ( msg.value.getConversionRate(priceFeed) >= MINIMUM_USD, "didn't send enough");

with this

 require ( msg.value.getConversionRate(priceFeed) >= MINIMUM_USD, "You need to spend more ETH!");

[pratokko]

and also in your test you ensure you have the correct spelling of need and the exact expected error, you have to ensure they match if not it will still not work

await expect(fundMe.fund()).to.be.revertedWith(
        "You need to spend more ETH!"
      );

[Glow-in-the-dark]

Ahhhh got it !!! Thanks a lot. Now i get what that expect().to.be.revertedWith() does. It's checking to error messaged to make sure it matched. Thank so much. @pratokko

[Glow-in-the-dark]

Separately, Not sure why my error codes doesn't revert as shown.

@pratokko Thanks alot for helping ! Super appreciative.
Error shown here:

FundMe.Sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.8;

import "./PriceConverter.sol"; // import library

//Error Codes
error FundMe__NotOwner();

contract FundMe {

// Type declarations
// State Variables
// Events
// Modifiers
// Functions

    using PriceConverter for uint256; // declare library for dataType.

    uint256 public constant MINIMUM_USD = 50 * 1e18; // * 1e18 cuz require statement we are comparing with eth in "wei".
  
    address[] public funders;
    mapping(address => uint256)public addressToAmountFunded;

    address public immutable i_owner;

    AggregatorV3Interface public priceFeed;

    // modifier onlyOwner {
    //     require(msg.sender == i_owner, "Sender is not Owner!");
    //     _; // This _; means run require the top code first (in this case, is the require statement), then the remaining code.
        
    //     // if it is:
    //     // 
    //     // _;
    //     // require(msg.sender == owner, "Sender is not Owner!");

    //     // then it means runs the func() code first, then run the "require" statement. (which in this case is not efficient.)
    // }

    modifier onlyOwner {
        if(msg.sender != i_owner) {revert FundMe__NotOwner();}
        _;
    }

As For the test file:
FundMe.test.js

    // ONLY allows owners to withdraw. Wen other accounts try to call, it gets reverted.
    it("Only allows the owner to withdraw", async function () {
      const accounts = await ethers.getSigners();
      const fundMeConnectedContract = await fundMe.connect(accounts[1]);
      // await expect(fundMeConnectedContract.withdraw()).to.be.reverted; // checked it it didn't went tru, and indeed reverted.

      await fundMeConnectedContract.withdraw();
      // but since we have error code already, for FundMe's owner modifider,
      await expect(fundMeConnectedContract.withdraw()).to.be.revertedWith(
        "FundMe__NotOwner"
      );
    });