bug: invalid BigNumber value "undefined" with gnosis safe app

[Max-3-7]

Is there an existing issue for this?

• I have searched the existing issues

Package Version

0.3.36

Current Behavior

Hey,

I'm having an issue with contract writes that require the value to be undefined when connected to a safe. It seems that the safe SDK doesn't like that viem sends undefined as value?

For example, this throws an error and you can't sign it from your safe:

const { config } = usePrepareContractWrite({
    abi: erc20ABI,
    address: token,
    args: amount ? [spender, amount] : undefined,
    chainId,
    functionName: 'approve',
})

But this works:

const { config } = usePrepareContractWrite({
    abi: erc20ABI,
    address: token,
    args: amount ? [spender, amount] : undefined,
    chainId,
    functionName: 'approve',
    value: BigInt(0) as any // workaround for safe app
})

Expected Behavior

No response

Steps To Reproduce

No response

Link to Minimal Reproducible Example (StackBlitz, CodeSandbox, GitHub repo etc.)

No response

Anything else?

No response

[jxom]

Can you raise this on the Safe SDK repo? That error looks like it’s coming from ethers via Safe SDK. This doesn’t look like to be a viem issue.

[Max-3-7]

safe-global/safe-apps-sdk#480 (comment)

That's the reply I got from the safe team

We can of course send 0 instead of undefined for every call that do not use value but it's very easy to miss.

You also have to ignore the typescript error that is thrown based on the ABI (which is correct, because there shouldn't be a value for these calls)

[mmv08]

sorry lads I misread the issue

[github-actions]

This issue has been locked since it has been closed for more than 14 days.

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