v4-core/test/utils/JavascriptFfi.sol

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.20;

import {CommonBase} from "forge-std/Base.sol";

abstract contract JavascriptFfi is CommonBase {
    function runScript(string memory scriptName, string memory args) internal returns (bytes memory result) {
        string[] memory inputs = new string[](8);

        // build ffi command string
        inputs[0] = "npm";
        inputs[1] = "--silent";
        inputs[2] = "--prefix";
        inputs[3] = "./test/js-scripts";
        inputs[4] = "run";
        inputs[5] = scriptName;
        inputs[6] = "--";
        inputs[7] = args;
        result = vm.ffi(inputs);
    }
}