[Ethereum] Gas estimation errored with the following message (see below). The transaction execution will likely fail. Do you want to force sending

solidity

I wrote one contract to call a function from another contract like below

pragma solidity ^0.5.1;

contract test3 {       
    address watch_addr = address(0x1234567963); //deployed contract address

    function balanceOf(address owner) public {
        watch_addr.call(abi.encodeWithSignature("balanceOf(address)", owner));
        return balanceOf(owner);
    }
}

I want to call a balanceOf function in deployed contract.Now I deployed the new contract successfully but I am getting the following error while calling the balanceOf function

error:"Gas estimation errored with the following message (see below).
The transaction execution will likely fail. Do you want to force
sending? "

Can any one please tell me the solution? –Thanks

Best Answer

You are calling balanceOf inside balanceOf , so it will be executed infinitely. Real estimation of gas for such actions are not possible or infinite. That's why you are getting this error. With smart contract, be damn sure with your logic.

Related Solutions

Gas Estimation Error – Understanding Common Issues in Solidity Remix

You usually get that error when code execution fails, this can be because of regular execution or because one of the reverts is catching an error, in your case, problem were the reverts, here is how you can find out:

This feature is not yet on nodes, only in in javascriptVM which you can use in remix, or in your truffle tests/ganache, but it's recommended that you start using it now; you can add an error message to your reverts, this is the easiest way to get better comprehensive errors, IE:

require(condition, "string returned if condition fails");

Note that I'm using javascript vm for this example instead of injected web3. When I execute your code, the first error we can find is in the second require:

require(block.number > drawing.drawBlock, "Can't draw yet");

We can't draw until some blocks have passed, I forced the generation of some blocks in the VM by calling other functions, if you are doing this on ethereum, you just need to wait.

After solving this problem, it crashed in the next line:

require(drawing.entries.length > 0, "No entries for that round");

So I called buy() a couple of times sending the amount of ether specified in TICKET_PRICE, then I checked that the entries where added by calling rounds(numberOfRound), and after calling drawWinner(numberOfRound) with a valid round, the function worked correctly.

You should create a call that will tell you if that function will work or it will fail by checking those conditions, that way you can solve a ton of headaches, remember to put error messages on require, and if you want to see everything step by step, the debugger provided in remix is pretty useful.

TLDR: For your code to work, you need to make sure that enough blocks have passed, and that the round has at least one entry.

By the way, there are a couple of vulnerabilities in your drawWinner() function, don't use it on production!

Gas Estimation Error – Fixing Gas Estimation Error in Solidity with Remix

You need to call the approve function directly from your wallet. You cant have your contract do that. So you'd need 2 transactions, one to the token contract that would be something like approve(yourContractAddress, amount) and one to your SimpleDeposit contract calling the simpleDeposit function with the parameters you want. The way you tried to do it by coding it wont work because the ERC20/BEP20 standard approve function simply doesnt work that way

Best Answer

Related Solutions

Gas Estimation Error – Understanding Common Issues in Solidity Remix

Gas Estimation Error – Fixing Gas Estimation Error in Solidity with Remix

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