[ address[] bytes[] ] to bytes memory calldata?

[Madeindreams]

Discussed in #2493

^{Originally posted by Madeindreams January 4, 2022}
I'm looking for a way to pass some arrays as one single bytes memory argument.

Example;

I have addresses and signed transaction.

address[] memory targets  // some addresses
bytes[] memory callData // some signed transaction to be called on targets

Right now what I do a simple transaction

        const iface = new ethers.utils.Interface(JSON.stringify(ABI));
        const sig = "transfer(address,uint256)";
        const data = iface.encodeFunctionData(sig, anAddress, anAmount)

  const tx = await signer.sendTransaction({
            to: mycontract
            data: data
        });

How do I create and array of bytes[] and addresses[] that can be passed as one single bytes argument to be decoded later in the call.

address[]   // the array of addresse, the targets
bytes[]      // the array of calls // signed transaction

addresses = [address,address,address]
callsData = [data, data, data]         

I need to turn these 2 arrays into a single bytes argument to this function

function iWantToCall(bytes memory callData){ 
// pass the calldata to another contract
 }

this other contract would come back in with the call data

function toBeCalledWithData(bytes memory callData) external {

// this is where i would decode my call data back to
MyStruct calls = decode(callData)

target = calls.target[0]
data = calls.callData[0]

target.call(data)

// and loop trough each entry to make the low lvl call

}

[ricmoo]

You can use:
utils.defaultAbiCoder.encode([ "address[]", "bytes[]" ], [ [ addr1, addr2 ], [ bytes1, bytes2 ] ])

Let me know if that helps. :)

[Madeindreams]

That worked! Thank you sir!

[Madeindreams]

Well I could get it to work but only by storing the calldata in the memory while the call is executed

Sequencer is a library that contains my struct.

function ToCall(Sequencer.TradeSequence memory callData){
  ongoingSequence = tradeData; this is working but i'm storing it until the calls come back
  
  // if I encode it
  
  bytes memory data = abi.encode(tradeData);
 // pass this data to the call
}

The decoding part isn't working after that

(address[] memory target, bytes[] memory callData) = abi.decode(
            params,
            (address[], bytes[])
        );

Maybe I should decode twice??

First

(bytes memory packed) = abi.decode(
            params,
            (bytes)
        );

Second

 (address[] memory target, bytes[] memory callData) = abi.decode(
            packed,
            (address[], bytes[])
        );

Thanks for your help @ricmoo