@safe-global/safe-contracts/test/accessors/SimulateTxAccessor.spec.ts

Ethereum multisig contract

import { expect } from "chai";
import hre, { deployments, waffle } from "hardhat";
import "@nomiclabs/hardhat-ethers";
import { deployContract, getSimulateTxAccessor, getSafeWithOwners, getCompatFallbackHandler } from "../utils/setup";
import { buildContractCall, executeTxWithSigners } from "../../src/utils/execution";
import { parseEther } from "ethers/lib/utils";

describe("SimulateTxAccessor", async () => {
    const killLibSource = `
    contract Test {
        function killme() public {
            selfdestruct(payable(msg.sender));
        }
    }`;
    const [user1, user2] = waffle.provider.getWallets();

    const setupTests = deployments.createFixture(async ({ deployments }) => {
        await deployments.fixture();
        const accessor = await getSimulateTxAccessor();
        const source = `
        contract Test {
            function sendAndReturnBalance(address payable target, uint256 amount) public returns (uint256) {
                (bool success,) = target.call{ value: amount }("");
                require(success, "Transfer failed");
                return target.balance;
            }
        }`;
        const interactor = await deployContract(user1, source);
        const handler = await getCompatFallbackHandler();
        const safe = await getSafeWithOwners([user1.address], 1, handler.address);
        const simulator = handler.attach(safe.address);
        return {
            safe,
            accessor,
            interactor,
            simulator,
        };
    });

    describe("estimate", async () => {
        it("should enforce delegatecall", async () => {
            const { accessor } = await setupTests();
            const killLib = await deployContract(user1, killLibSource);
            const tx = buildContractCall(killLib, "killme", [], 0);

            const code = await hre.ethers.provider.getCode(accessor.address);
            await expect(accessor.simulate(tx.to, tx.value, tx.data, tx.operation)).to.be.revertedWith(
                "SimulateTxAccessor should only be called via delegatecall",
            );

            expect(await hre.ethers.provider.getCode(accessor.address)).to.be.eq(code);
        });

        it("simulate call", async () => {
            const { safe, accessor, simulator } = await setupTests();
            const tx = buildContractCall(safe, "getOwners", [], 0);
            const simulationData = accessor.interface.encodeFunctionData("simulate", [tx.to, tx.value, tx.data, tx.operation]);
            const acccessibleData = await simulator.callStatic.simulate(accessor.address, simulationData);
            const simulation = accessor.interface.decodeFunctionResult("simulate", acccessibleData);
            expect(safe.interface.decodeFunctionResult("getOwners", simulation.returnData)[0]).to.be.deep.eq([user1.address]);
            expect(simulation.success).to.be.true;
            expect(simulation.estimate.toNumber()).to.be.lte(10000);
        });

        it("simulate delegatecall", async () => {
            const { safe, accessor, interactor, simulator } = await setupTests();
            await user1.sendTransaction({ to: safe.address, value: parseEther("1") });
            const userBalance = await hre.ethers.provider.getBalance(user2.address);
            const tx = buildContractCall(interactor, "sendAndReturnBalance", [user2.address, parseEther("1")], 0, true);
            const simulationData = accessor.interface.encodeFunctionData("simulate", [tx.to, tx.value, tx.data, tx.operation]);
            const acccessibleData = await simulator.callStatic.simulate(accessor.address, simulationData);
            const simulation = accessor.interface.decodeFunctionResult("simulate", acccessibleData);
            expect(interactor.interface.decodeFunctionResult("sendAndReturnBalance", simulation.returnData)[0]).to.be.deep.eq(
                userBalance.add(parseEther("1")),
            );
            expect(simulation.success).to.be.true;
            expect(simulation.estimate.toNumber()).to.be.lte(15000);
        });

        it("simulate selfdestruct", async () => {
            const { safe, accessor, simulator } = await setupTests();
            const expectedCode = await hre.ethers.provider.getCode(safe.address);
            await user1.sendTransaction({ to: safe.address, value: parseEther("1") });
            const killLib = await deployContract(user1, killLibSource);
            const tx = buildContractCall(killLib, "killme", [], 0, true);
            const simulationData = accessor.interface.encodeFunctionData("simulate", [tx.to, tx.value, tx.data, tx.operation]);
            await simulator.simulate(accessor.address, simulationData);
            const code = await hre.ethers.provider.getCode(safe.address);
            expect(code).to.be.eq(expectedCode);
            expect(code).to.be.not.eq("0x");
            // Selfdestruct Safe (to be sure that this test works)
            await executeTxWithSigners(safe, tx, [user1]);
            expect(await hre.ethers.provider.getCode(safe.address)).to.be.eq("0x");
        });

        it("simulate revert", async () => {
            const { accessor, interactor, simulator } = await setupTests();
            const tx = buildContractCall(interactor, "sendAndReturnBalance", [user2.address, parseEther("1")], 0, true);
            const simulationData = accessor.interface.encodeFunctionData("simulate", [tx.to, tx.value, tx.data, tx.operation]);
            const acccessibleData = await simulator.callStatic.simulate(accessor.address, simulationData);
            const simulation = accessor.interface.decodeFunctionResult("simulate", acccessibleData);
            expect(simulation.returnData).to.be.deep.eq(
                "0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000f5472616e73666572206661696c65640000000000000000000000000000000000",
            );
            expect(simulation.success).to.be.false;
            expect(simulation.estimate.toNumber()).to.be.lte(20000);
        });
    });
});