I'm testing a covered-call option smart contract in hardhat - specifically the execute function where the call buyer executes the option at a specific trike price. However I keep getting a transaction revert with no reason and I'm not sure how to solve it.

Here is my smart contract:

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.0;

contract CoveredCallContract {

    address public callWriter;
    address public callBuyer;
    uint public amount;
    uint public optionPrice;
    uint public strikePrice;
    uint public expiryDate;
    bool wasPurchased;

    constructor(uint _amount, uint _optionPrice, uint _strikePrice) {
        callWriter = msg.sender;
        amount = _amount;
        optionPrice = _optionPrice;
        strikePrice = _strikePrice;
        expiryDate = block.timestamp + 1 weeks;

    // this function is how the callwriter deposits the collateral to cover the option
    function depositCollateral() public payable {
        require(msg.value >= amount, " Insufficient balance");

    // this function allows the buyer to purchase the contract and pay the premium
    function purchaseOption() external payable {
        // ensure buyer hasn't already bought the option
        require(wasPurchased == false);
        // ensure buyer sends the correct amount
        require(msg.value == optionPrice, "Incorrect purchase price");
        // set the option buyer to the callbuyer
        callBuyer = msg.sender;
        // if the buyer buys the option, the price is transfered directly to the writer
        // set the wasPurchased to true one the option has been purchased
        wasPurchased = true;


    // the option will be executed if the price of ETH is above the strike price 
    function executeOption() external payable {
        // ensure the buyer has purchased the option
        require(wasPurchased == true);
        // make sure it's the buyer executing the contract
        require(msg.sender == callBuyer, "Unauthorized");
        // ensure the contract has been funded by the call writer
        require(address(this).balance == amount, "Funding error");
        // ensure the amount the buyer pays at execution is equal to the strikeprice
        require(msg.value == strikePrice, "Payment error");
        // make sure the contract has not expired
        require(block.timestamp < expiryDate, "Option has already expired");
        // if all the above hold transfer the amount to the buyer

    // if the option is not executed the initial funds will be sent back to the call writer
    function refund() public payable {
        if(wasPurchased == false) {
            require(block.timestamp >= expiryDate, "Option has not expired yet");    

Here is the test to test the execute function:

describe("CoveredCallContract", function () {

  let coveredCallContract;
  let callWriter;
  let callBuyer;
  const amount = ethers.utils.parseEther("1");
  const optionPrice = ethers.utils.parseEther("0.1");
  const strikePrice = ethers.utils.parseEther("1.5");

  this.beforeEach(async () => {
    [callWriter, callBuyer] = await ethers.getSigners();
    const CoveredCallContract = await ethers.getContractFactory("CoveredCallContract");
    coveredCallContract = await CoveredCallContract.deploy(amount, optionPrice, strikePrice);
    await coveredCallContract.deployed();

it(**'should execute option'**, async () => {
    await coveredCallContract.connect(callBuyer).executeOption({value: strikePrice});

I'm pretty new to solidity and coding generally so any advice would be greatly appreciated.

1 Answer 1


In the executeOption function, the first require misses a revert messages.

    // the option will be executed if the price of ETH is above the strike price 
    function executeOption() external payable {
        // ensure the buyer has purchased the option
        require(wasPurchased == true);

Here your contract likely fails (without a error message). Based on the contract logic, you should call purchaseOption first. You can use console.log to get more information about the contract state during execution.

  • as in use console.log in the smart contract or the JS test - just to clarify?
    – 0xJI
    Dec 8, 2022 at 17:57

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