[Deployment] EVM -> zkVM call not working

[coffeexcoin]

Team or Project

Abstract

ZK chain

Abstract

Environment

Testnet

L2 block number

No response

zkSolc Version

N/A (EVM contract)

zksync-ethers Version

N/A

Minimal Reproducible Code or Repo Link

https://github.com/coffeexcoin/evm-zkvm-constructor-call

Does this work on other EVMs? (If yes, please list at least 1 of them)

yes, all other EVMs (when using proper position manager address)

Description of What Your Contract Does

Stores the uniswap v3 factory address as part of constructor/initialization

Repro:
Attempt to deploy contract to testnet, use --skip-simulation as recommended and observe revert

cp .env.example .env
forge script script/DeployFactoryCache.sol --rpc-url https://api.testnet.abs.xyz --skip-simulation --broadcast --account MY_ACCOUNT
[⠊] Compiling...
No files changed, compilation skipped
Enter keystore password:
Traces:
  [304399] → new DeployFactoryCache@0x9f7cF1d1F558E57ef88a59ac3D47214eF25B6A06
    └─ ← [Return] 1408 bytes of code

  [121] DeployFactoryCache::setUp()
    └─ ← [Stop]

  [38110] DeployFactoryCache::run()
    ├─ [0] VM::startBroadcast()
    │   └─ ← [Return]
    ├─ [2876] → new <unknown>@0x08173Bf13896E81a85793C9f6143737bc9894B44
    │   ├─ [0] 0x069f199763c045A294C7913E64bA80E5F362A5d7::factory() [staticcall]
    │   │   └─ ← [Stop]
    │   └─ ← [Revert]
    └─ ← [Revert] EvmError: Revert


Error: script failed: <empty revert data

Note that the factory call is in fact valid:

cast call 0x069f199763c045A294C7913E64bA80E5F362A5d7 "factory()(address)" --rpc-url https://api.testnet.abs.xyz
0x2E17FF9b877661bDFEF8879a4B31665157a960F0

Additional Details

No response

[coffeexcoin]

Update - it looks like this is forge script specific, and not a protocol level issue. forge create works okay, but very undesirable for anyone building larger multi-contract protocols with big deployment scripts or complex parameter sets.

[dutterbutter]

hmm interesting. I will pick this up and review. BTW once this PR is merged / released you no longer will need to pass --skip-simulation

[dutterbutter]

I just want to clarify some info for this ticket:

• Running the script with --zksync flag works without issue, but I am assuming that we want the FactoryCache contract to be an EVM contract, is that correct?
• If the above is correct, you can still achieve this behaviour, albeit with slight changes. See below for details:

src/FactoryCache.sol

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.13;

import {IUniswapPositionManager} from "./IUniswapPositionManager.sol";

contract FactoryCache {
    address public immutable factory;

    constructor(address _factory) {
        factory = _factory;
    }
}

script/DeployFactoryCache.s.sol

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.13;

import {Script, console} from "forge-std/Script.sol";
import {FactoryCache} from "../src/FactoryCache.sol";
import {IUniswapPositionManager} from "../src/IUniswapPositionManager.sol";
import {ScriptExt} from "forge-zksync-std/ScriptExt.sol";

contract DeployFactoryCache is Script, ScriptExt {
    FactoryCache public factoryCache;

    function run() public {        
        address uniswapPositionManager = vm.envAddress("UNISWAP_POSITION_MANAGER");

        vm.startBroadcast();

        vmExt.zkVm(true);
        address factory = IUniswapPositionManager(uniswapPositionManager).factory();

        vmExt.zkVm(false);
        factoryCache = new FactoryCache(factory);

        vm.stopBroadcast();
    }
}

Run:

forge script script/DeployFactoryCache.s.sol --skip-simulation --rpc-url https://api.testnet.abs.xyz  --broadcast --account test-acct -vvvvv --zksync

This will call factory() via EraVM but deploy FactoryCache as EVM contract.

[dutterbutter]

As you suggested, its not a protocol issue, but rather a tooling issue I believe. foundry-zksync with --zksync was designed for EraVM usage, whereas without --zksync flag is designed for EVM. We currently do not have a lot of support for interacting between the two environments.

[coffeexcoin]

Running the script with --zksync flag works without issue, but I am assuming that we want the FactoryCache contract to be an EVM contract, is that correct?

Correct - the factory cache (this was just a minimal repro I put together to help someone else) is being deployed as EVM, but is calling a read function on the position manager in its constructor.

Can you clarify why/how this fixes the issue? Does the constructor call when running the script somehow use a cached value from the call to factory() in the line above?

[dutterbutter]

The adjustments I made cleanly divides the EraVM / EVM contract interactions for foundry-zksync. More specifically, I believe the reasoning as:

What went wrong

• FactoryCache is being compiled as an EVM contract using solc.
• Inside its constructor it tries to execute IUniswapPositionManager(upm).factory(); against the UniswapPositionManager, which was compiled with zksolc .
• When an EVM contract calls an EraVM contract in the same transaction, EraVM returns an empty returndata buffer.
• Solidity’s ABI decoder expects 32 bytes and reverts, so the whole deployment fails with empty revert data.

Why the updated script works

vmExt.zkVm(true);                                             //  temporarily switch the script runner to EraVM
address factory = IUniswapPositionManager(upm).factory();     // read the value successfully
vmExt.zkVm(false);                                           // switch back to EVM
factoryCache = new FactoryCache(factory);                    // deploy as an EVM contract

Nothing is cached. We moved the EraVM call outside the constructor and executed it in the correct VM first, then passed the result into an EVM constructor that no longer needs to talk to EraVM.

[dutterbutter]

I am going to mark this as answered. Please feel free to mark unanswered if they're any followup questions / concerns actions.