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Cannot read properties of undefined (reading 'toHexString')

See original GitHub issue

Ethers Version

^5.0.0

Search Terms

No response

Describe the Problem

I am trying to execute a transaction and I get

TypeError: Cannot read properties of undefined (reading 'toHexString')
    at isHexable (/node_modules/@ethersproject/bytes/src.ts/index.ts:58:21)
    at arrayify (/node_modules/@ethersproject/bytes/src.ts/index.ts:115:9)
    at FixedBytesCoder.encode (/node_modules/@ethersproject/abi/src.ts/coders/fixed-bytes.ts:22:28)
    at /node_modules/@ethersproject/abi/src.ts/coders/array.ts:71:19
    at Array.forEach (<anonymous>)
    at pack (//node_modules/@ethersproject/abi/src.ts/coders/array.ts:54:12)
    at TupleCoder.encode (/node_modules/@ethersproject/abi/src.ts/coders/tuple.ts:54:20)
    at /node_modules/@ethersproject/abi/src.ts/coders/array.ts:62:19
    at Array.forEach (<anonymous>)
    at pack (/node_modules/@ethersproject/abi/src.ts/coders/array.ts:54:12)

Code Snippet

https://github.com/Dimo99/light-client-smart-contract

in this repo run `npx hardhat deploy`

The json file I am loading is this one `https://github.com/metacraft-labs/eth2-light-client-updates/blob/main/mainnet/updates/00290.json`

Contract ABI

No response

Errors

TypeError: Cannot read properties of undefined (reading 'toHexString')
    at isHexable (/node_modules/@ethersproject/bytes/src.ts/index.ts:58:21)
    at arrayify (/node_modules/@ethersproject/bytes/src.ts/index.ts:115:9)
    at FixedBytesCoder.encode (/node_modules/@ethersproject/abi/src.ts/coders/fixed-bytes.ts:22:28)
    at /node_modules/@ethersproject/abi/src.ts/coders/array.ts:71:19
    at Array.forEach (<anonymous>)
    at pack (//node_modules/@ethersproject/abi/src.ts/coders/array.ts:54:12)
    at TupleCoder.encode (/node_modules/@ethersproject/abi/src.ts/coders/tuple.ts:54:20)
    at /node_modules/@ethersproject/abi/src.ts/coders/array.ts:62:19
    at Array.forEach (<anonymous>)
    at pack (/node_modules/@ethersproject/abi/src.ts/coders/array.ts:54:12)

Environment

Hardhat

Environment (Other)

No response

Issue Analytics

State:
Created a year ago
Comments:6 (3 by maintainers)

Top GitHub Comments

2reactions

ricmoocommented, Aug 9, 2022

@Dimo99 Thats directly from the JavaScript language and runtime. There isn’t much I can do about that… it has nothing to do with ethers. If you have an undefined value (in any variable) and attempt to access a property on it, JS (correctly) complains. 😃

0reactions

Dimo99commented, Aug 9, 2022

@ricmoo actually fork_version was part of my structure. This is the most minimalistic example.

contract Example {
    struct FinalizedHeaderUpdate {
        bytes4 fork_version;
    }

    function light_client_update(FinalizedHeaderUpdate calldata update) external {
        require(2 > 1, "Test");
    }
}

    const result = await exampleContract.light_client_update({asd: "asd"}); // fails with Cannot read properties of undefined (reading 'toHexString')

    const result1 = await exampleContract.light_client_update({fork_version: "0x00000000"}); // works properly

I know the first statement is expected to fail. But I guess Cannot read properties of undefined (reading 'toHexString') is not a nice message