I writing a contract for Staking Token to earn Token. It's similar to pancake MasterChef. The requirement is based on timestamp (not block). When I test the contract with hardhat, I call the deposit function then time increases, so I can't calculate exactly how many tokens I can withdraw. The deposit function:

    function deposit(uint256 _amount) public payable {
        require(rewardsStartTime <= block.timestamp, "Staking has not started");
        require(rewardsExpiration >= block.timestamp, "Staking has ended");
        UserInfo storage user = userInfo[msg.sender];
        if (_amount > 0) {
            user.amount = user.amount.add(_amount);
            if (msg.value > 0) {
                require(stakedToken == WETH_ADDRESS, "SmartBaryFactory: Invalid LP Token");

                IWETH(WETH_ADDRESS).deposit{ value: msg.value }();
            } else {
                IERC20(stakedToken).transferFrom(address(msg.sender), address(this), _amount);
            tokenShare = tokenShare.add(_amount);
        for (uint256 i = 0; i < rewardTokens.length; i++) {
            user.rewardDebt[rewardTokens[i]] = user.amount.mul(accRewardPerShare[rewardTokens[i]]).div(

The test function:

it("Should deposit bnb to fungible pool", async function () {
        const Pool = await ethers.getContractFactory("ERC20Pool");
        bnbPool = Pool.attach(bnbPoolAddress);

        console.log("bnb Pool: ", bnbPool.address);

        // Mint bnb to Account 1
        await bnb.connect(acc1).mint(parseEther("10000"));

        // Check balance of Account 1
        expect(await bnb.balanceOf(acc1.address)).to.equal(parseEther("10000"));

        // Approve bnb to pool
        await bnb.connect(acc1).approve(bnbPoolAddress, parseEther("10000"));

        // Check timestamp
        console.log("Time: ", await time.latest());

        // Increase time to reward start time
        await time.increaseTo(rewardStartTime);

        // Deposit bnb to pool
        await bnbPool.connect(acc1).deposit(parseEther("10000"));

        // Check timestamp
        console.log("Time deposit: ", await time.latest());

        // Check balance of Account 1
        expect(await bnb.balanceOf(acc1.address)).to.equal(0);

        // Check balance of bnb pool
        expect(await bnb.balanceOf(bnbPool.address)).to.equal(parseEther("10000"));

        // Increase time to reward expiration
        await time.increaseTo(rewardExpiration + 100);

        // Check timestamp
        console.log("Time withdraw: ", await time.latest());

        // Withdraw bnb from pool
        await bnbPool.connect(acc1).withdraw(parseEther("10000"));

        // Check balance of Account 1
        expect(await bnb.balanceOf(acc1.address)).to.equal(parseEther("10000"));

        // Check balance of bnb pool
        expect(await bnb.balanceOf(bnbPool.address)).to.equal(0);

        // Check reward of Account 1
        expect(await usdc.balanceOf(acc1.address)).to.equal(parseEther("1000"));
        expect(await usdt.balanceOf(acc1.address)).to.equal(parseEther("1000"));

The pool is 1000 USDT and 1000 USDC to pool. But when I deposit BNB to pool, timestamp is late for 1 second. I just receive 990 token return.

AssertionError: expected 990000000000000000000 to equal 1000000000000000000000. The numerical values of the given "ethers.BigNumber" and "ethers.BigNumber" inputs were compared, and they differed.
      + expected - actual

I want to test with exact timestamp. How can I do it?

1 Answer 1


Have you tried time.setNextBlockTimestamp?

Or just try await time.increaseTo(rewardExpiration + 100 -1);

  • time.setNextBlockTimestamp is not suitable for this purpose. It's can't change the time of block.timestamp. await time.increaseTo(rewardExpiration + 100 -1); is not the best practice. The transaction maybe late more than 1 second. So it's will be wrong
    – MadTik
    Commented Feb 28 at 10:01
  • Why can't it change the time of block timestamp? All three functions: increase,increaseTo or setNextBlockTimestamp refers to evm_setNextBlockTimestamp. All three of them are the same, just utilities. Btw I can't get your concept without withdraw function, could you update your question?
    – CT95
    Commented Feb 29 at 4:50

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