New RPC endpoint: eth_balanceDeltaBundle about mev-geth

[libevm]

It would be great to make this as generic as possible and not limit it to certain standards i.e. ERC20 / ERC721.

My API proposal would be something like:

method: 'eth_balanceDeltaBundle'

params: [{
    balanceDelta: [
        // This should return a uint256, for a future PR, we could add a "formatter" akin to the debug_trace*
        // JavaScript runtime environment
        { address: '0x0...', data: '0x0....' } 
    ],
    txs: [ ], // signed or unsigned txs, same as callBundle
    stateBlockNumber: 1,
    blockNumber: 1
}]

For now we can just assume all balances is uint256, and the response should be roughly:

result: {
    balanceDelta: [
        { delta: 100 }
    ],
    txs: [ ... ] // normal callBundle tx return
}

Let me know your thoughts

[thegostep]

For now we can just assume all balances is uint256

I like the simplicity of this api. By convention we can deem a null data field to return the ETH balance.

Care must be taken for the result to be an array of signed 256 bit integers.

[thegostep]

An even more generalized api would be a pre-flight and post-flight multicall. Though this is probably overkill.

Something like this:

method: 'eth_balanceDeltaBundle'

params: [{
    preCheck: [
        { address: '0x0...', data: '0x0....' } 
    ],
    postCheck: [
        { address: '0x0...', data: '0x0....' } 
    ],
    txs: [ ], // signed or unsigned txs, same as callBundle
    stateBlockNumber: 1,
    blockNumber: 1
}]

result: {
    preCheck: [
        { result: '0x0....' }
    ],
    postCheck: [
        { result: '0x0....' }
    ],
    txs: [ ... ] // normal callBundle tx return
}