scam-test.js

// ethers is global variable here.
const { expect } = require("chai");
const { expectRevert } = require('@openzeppelin/test-helpers');
// 1.
const totalSupplyBigNumberHex = ethers.BigNumber.from("0x52b7d2dcc80cd2e4000000");
const preMineBigNumberHex = ethers.BigNumber.from("0x108b2a2c28029094000000");
const airDropSize = "1000000000000000000000000"; // "0xD3C21BCECCEDA1000000"
describe("SCAMToken state and transactions", function () {
  let SCAMToken, scamToken, owner, firstComer, secondComer; // seller is owner
  // We don't include events here 
  // because it was already handled in the previous post
  beforeEach(async () => {
    provider = ethers.getDefaultProvider();
    SCAMToken = await ethers.getContractFactory("SCAM_Token");
    scamToken = await SCAMToken.deploy();
    [owner, firstComer, secondComer, _] = await ethers.getSigners();
  });
  it("Should test 'totalSupply' and other default values.", async function () {
    // 2.
    expect(await scamToken.symbol()).to.equal("SCAM");
    expect(await scamToken.name()).to.equal("Safe Crypto And Money");
    expect(await scamToken.decimals()).to.equal(18);
    const totalSupply = await scamToken.totalSupply();
    expect(totalSupply).to.equal(totalSupplyBigNumberHex);
    // What the owner takes from the total supply
    const preMine = await scamToken.balanceOf(owner.address);
    expect(preMine).to.equal(preMineBigNumberHex);
  });
  it("Should test 'airdropTokens' and the contract and receiver balance change.", async function () {
    // 3.
    await expectRevert.unspecified(scamToken.connect(firstComer).airdropTokens(firstComer.address));
    await expectRevert.unspecified(scamToken.connect(secondComer).airdropTokens(secondComer.address));
    // From contract to a user
    await scamToken.airdropTokens(firstComer.address);
    // Include contract balance also here.
    const firstComerBalance = await scamToken.balanceOf(firstComer.address);
    expect(firstComerBalance.toString()).to.equal(airDropSize);
  });
  // 4.
  it("Should test 'transfer' from the owner to firstComer.", async function () {
    // From a user to another user
    const amountToTransfer = 1000000;
    await scamToken.transfer(firstComer.address, amountToTransfer);
    let firstComerBalance = await scamToken.balanceOf(firstComer.address);
    expect(firstComerBalance.toString()).to.equal(amountToTransfer.toString());
  });
  it("Should test 'approve' and 'allowance' from the owner to firstComer.", async function () {
    const amountForApproval = 1000000;
    await scamToken.approve(firstComer.address, amountForApproval);
    const allowance = await scamToken.allowance(owner.address, firstComer.address);
    expect(allowance.toString()).to.equal(amountForApproval.toString());
  });
  it("Should test 'approve', 'allowance' and 'transferFrom'.", async function () {
    const amountForApproval = 1000000;
    await scamToken.approve(firstComer.address, amountForApproval);
    const allowance = await scamToken.allowance(owner.address, firstComer.address);
    expect(allowance.toString()).to.equal(amountForApproval.toString());
    await scamToken.connect(firstComer).transferFrom(owner.address, secondComer.address, amountForApproval);
    const secondComerBalance = await scamToken.balanceOf(secondComer.address);
    expect(secondComerBalance.toString()).to.equal(amountForApproval.toString());
  });
  // 5.
  it("Should test 'releaseBNB' and it shouldn't affect the balance of other users (not owners)", async function () {
    const amountForApproval = 1000000;
    await scamToken.approve(firstComer.address, amountForApproval);
    const allowance = await scamToken.allowance(owner.address, firstComer.address);
    expect(allowance.toString()).to.equal(amountForApproval.toString());
    await scamToken.connect(firstComer).transferFrom(owner.address, secondComer.address, amountForApproval);
    const secondComerBalance = await scamToken.balanceOf(secondComer.address);
    expect(secondComerBalance.toString()).to.equal(amountForApproval.toString());
    await scamToken.releaseBNB();
    expect(secondComerBalance.toString()).to.equal(amountForApproval.toString());
  });
});