TypeError: interval.toNumber is not a function

[SamarthBagga]

while writing tests in raffle.text.js-

const { network, getNamedAccounts, deployments, ethers } = require("hardhat")
const { developmentChains, networkConfig } = require("../../helper-hardhat-config")
const { isCallTrace } = require("hardhat/internal/hardhat-network/stack-traces/message-trace")
const { assert, expect } = require("chai")

!developmentChains.includes(network.name)
    ? describe.skip
    : describe("Raffle Uint tests", async function () {
          let raffle, vrfCoordinatorV2Mock, raffleEntranceFee, deployer, interval
          const chainId = network.config.chainId

          beforeEach(async function () {
              deployer = (await getNamedAccounts()).deployer
              await deployments.fixture(["all"])
              raffle = await ethers.getContract("Raffle", deployer)
              vrfCoordinatorV2Mock = await ethers.getContract("VRFCoordinatorV2Mock", deployer)
              raffleEntranceFee = await raffle.getEntranceFee()
              interval = await raffle.getInterval()
          })

          describe("constructor", async function () {
              it("initializes the raffle correctly", async function () {
                  const raffleState = await raffle.getRaffleState()
                  assert.equal(raffleState.toString(), "0")
                  assert.equal(interval.toString(), networkConfig[chainId]["interval"])
              })
          })

          describe("enterRaffle", async function () {
              it("reverts when you dont pay enough", async function () {
                  await expect(raffle.enterRaffle()).to.be.revertedWith(
                      "Raffle__NotEnoughETHEntered",
                  )
              })
              it("records players when they enter", async function () {
                  await raffle.enterRaffle({ value: raffleEntranceFee })
                  const playerFromContract = await raffle.getPlayer(0)
                  assert.equal(playerFromContract, deployer)
              })
              it("emits event on enter", async function () {
                  await expect(raffle.enterRaffle({ value: raffleEntranceFee })).to.emit(
                      raffle,
                      "RaffleEnter",
                  )
              })
              it("doesnt allow entrace when raffle is calculating", async function () {
                  await raffle.enterRaffle({ value: raffleEntranceFee })
                  await network.provider.send("evm_increaseTime", [interval.toNumber() + 1])
                  await network.provider.send("evm_mine", [])
                  await raffle.performUpkeep([])
                  await expect(raffle.enterRaffle({ value: raffleEntranceFee })).tp.be.revertedWith(
                      "Raffle__NotOpen",
                  )
              })
          })
      })

[alfaqi]

Because you are using ethersV6, it changed BigNumber to BigInt, and toNumber function is member of BigNumber.
you can use Number function that's come with JS, like this

await network.provider.send("evm_increaseTime", [Number(interval) + 1])

and there are some issues with your test:
1- change [] to "0x"

await raffle.performUpkeep("0x")

(I'm not sure about this)
2- instead of revertedWith(...), use revertedWithCustomError without message

[SamarthBagga]

hi @alfaqi I have made the edits you suggested, only 1 test is not passing and it is giving this error-

AssertionError: expected '30' to equal undefined

test file-

const { network, getNamedAccounts, deployments, ethers } = require("hardhat")
const { developmentChains, networkConfig } = require("../../helper-hardhat-config")
const { isCallTrace } = require("hardhat/internal/hardhat-network/stack-traces/message-trace")
const { assert, expect } = require("chai")

!developmentChains.includes(network.name)
    ? describe.skip
    : describe("Raffle Uint tests", async function () {
          let raffle, vrfCoordinatorV2Mock, raffleEntranceFee, deployer, interval
          const chainId = network.config.chainId

          beforeEach(async function () {
              deployer = (await getNamedAccounts()).deployer
              await deployments.fixture(["all"])
              raffle = await ethers.getContract("Raffle", deployer)
              vrfCoordinatorV2Mock = await ethers.getContract("VRFCoordinatorV2Mock", deployer)
              raffleEntranceFee = await raffle.getEntranceFee()
              interval = await raffle.getInterval()
          })

          describe("constructor", async function () {
              it("initializes the raffle correctly", async function () {
                  const raffleState = await raffle.getRaffleState()
                  assert.equal(raffleState.toString(), "0")
                  assert.equal(interval.toString(), networkConfig[chainId]["interval"])
              })
          })

          describe("enterRaffle", async function () {
              it("reverts when you dont pay enough", async function () {
                  await expect(raffle.enterRaffle()).to.be.revertedWithCustomError(
                      raffle,
                      "Raffle__SendMoreToEnterRaffle",
                  )
              })
              it("records players when they enter", async function () {
                  await raffle.enterRaffle({ value: raffleEntranceFee })
                  const playerFromContract = await raffle.getPlayer(0)
                  assert.equal(playerFromContract, deployer)
              })
              it("emits event on enter", async function () {
                  await expect(raffle.enterRaffle({ value: raffleEntranceFee })).to.emit(
                      raffle,
                      "RaffleEnter",
                  )
              })
              it("doesnt allow entrace when raffle is calculating", async function () {
                  await raffle.enterRaffle({ value: raffleEntranceFee })
                  await network.provider.send("evm_increaseTime", [Number(interval) + 1])
                  await network.provider.send("evm_mine", [])
                  await raffle.performUpkeep("0x")
                  await expect(
                      raffle.enterRaffle({ value: raffleEntranceFee }),
                  ).to.be.revertedWithCustomError(raffle, "Raffle__RaffleNotOpen")
              })
              describe("checkUpkeep", async function () {
                  it("returns false if people haven't sent any ETH", async function () {
                      await network.provider.send("evm_increaseTime", [Number(interval) + 1])
                      await network.provider.send("evm_mine", [])
                      await raffle.checkUpkeep("0x")
                  })
              })
          })
      })

and helper hardhat file-

const { ethers } = require("hardhat")

const networkConfig = {
    default: {
        name: "hardhat",
        keepersUpdateInterval: "30",
    },
    111555111: {
        name: "sepolia",
        vrfCoordinatorV2: "0x271682DEB8C4E0901D1a1550aD2e64D568E69909",
        raffleEntranceFee: ethers.parseEther("0.01"),
        gasLane: "0x474e34a077df58807dbe9c96d3c009b23b3c6d0cce433e59bbf5b34f823bc56c",
        subscriptionId: "0",
        callbackGasLimit: "500000",
        keepersUpdateInterval: "30",
    },
    31337: {
        name: "hardhat",
        subscriptionId: "6926",
        raffleEntranceFee: ethers.parseEther("0.01"),
        gasLane: "0x474e34a077df58807dbe9c96d3c009b23b3c6d0cce433e59bbf5b34f823bc56c",
        keepersUpdateInterval: "30",
        callbackGasLimit: "500000",
    },
}

const developmentChains = ["hardhat", "localhost"]

module.exports = {
    networkConfig,
    developmentChains,
}

[alfaqi]

change interval to keepersUpdateInterval

assert.equal(interval.toString(), networkConfig[chainId]["keepersUpdateInterval"])

and sepolia chain id is 11155111 not 111555111

[SamarthBagga]

yes thank you it worked!