Lesson 9: error in final staging test

[yash-2138]

While performing the final staging test getting this error
AssertionError: expected '268982146109979949' to equal '278982146109979949'

raffle.staging.test.js

const { assert,expect } = require("chai");
const { network, getNamedAccounts, ethers } = require("hardhat");
const {developmentChains, networkConfig} = require("../../helper-hardhat-config")


developmentChains.includes(network.name)
    ?describe.skip
    :describe("Raffle Unit Tests",  function(){
        let raffle, raffleEntranceFee, deployer 

        beforeEach(async function(){
            deployer = (await getNamedAccounts()).deployer
            raffle = await ethers.getContract("Raffle", deployer)
            raffleEntranceFee = await raffle.getEntranceFee()
        })
        describe("fulfillRandomWords", function(){
            it("works with live chainlink keepers and chainlink vrf, we get a random winner", async function(){
                //enter raffle
                console.log("Setting up test...")
                const startingTimeStamp = await raffle.getLatestTimeStamp()
                const accounts = await ethers.getSigners()
                await new Promise(async (resolve, reject) =>{
                    //setup listner before we enter the raffle
                    //just in case the blockchain moves really fast
                    raffle.once("WinnerPicked", async function(){
                        console.log("WinnerPicked event fired!")
                       
                        try{
                            //add our asserts here
                            const recentWinner = await raffle.getRecentWinner()
                            const raffleState = await raffle.getRaffleState()
                            const WinnerEndingBalance = await accounts[0].getBalance()
                            const endingTimeStamp = await  raffle.getLatestTimeStamp()
                            const winnerStartingBalance = await accounts[0].getBalance()

                            await expect(raffle.getPlayer(0)).to.be.reverted  //there will not be any object at 0 
                            //another way to see that our players array is reset
                            assert.equal(recentWinner.toString(), accounts[0].address)
                            assert.equal(raffleState.toString(), "0") 
                            assert.equal(WinnerEndingBalance.toString(), winnerStartingBalance.add(raffleEntranceFee).toString())
                            assert(endingTimeStamp > startingTimeStamp)
                            resolve()
                        }catch(error){
                            console.log(error)
                            reject(error)
                        }
                    })
                    //then entering the raffle
                    
                    console.log("Entering Raffle...")
                    await raffle.enterRaffle({value: raffleEntranceFee})
                    
                    //and this code wont run until the listner has finished listning
                })
                
            }) 
        })
    })

https://github.com/yash-2138/hardhat-smartcontract-lottery

[RoboCrypter]

@yash-2138 : Alright let me check, will let know soon!

[othaime-en]

Hey @yash-2138 I've made a PR. See if that fixes the issue.
I've rearranged the position of your const winnerStartingBalance = await accounts[0].getBalance() and added a few lines.

[yash-2138]

Thanks @othaime-en it worked . Can you tell why was that error occurring ?

[othaime-en]

Hey @yash-2138 you needed to initialize the starting balance immediately after you joined the lottery and before the ending balance. But in your case, you were initializing the starting balance after getting the endingBalance which is logically incorrect.