README.md

EigenLayer Core Integration Testing

What the Hell?

Good question.

This folder contains the integration framework and tests for Eigenlayer core, which orchestrates the deployment of all EigenLayer core contracts to fuzz high-level user flows across multiple user and asset types, and supports time-travelling state lookups to quickly compare past and present states (please try to avoid preventing your own birth).

If you want to know where the tests are, take a look at /tests. We're doing one test contract per top-level flow, and defining multiple test functions for variants on that flow.

e.g. if you're testing the flow "deposit into strategies -> delegate to operator -> queue withdrawal -> complete withdrawal", that's it's own test contract. For variants where withdrawals are completed "as tokens" vs "as shares," those are their own functions inside that contract.

Looking at the current tests is a good place to start.

If you want to know how we're fuzzing these flows, take a look at how we're using the _configRand method at the start of each test, which accepts bitmaps for the types of users and assets you want to spawn during the test.

During the test, the config passed into _configRand will randomly generate only the values you configure:

• assetTypes affect the assets granted to Users when they are first created. You can use this to ensure your flows and assertions work when users are holding only LSTs, native ETH, or some combination.
• userTypes affect the actual User contract being deployed. The DEFAULT flag deploys the base User contract, while ALT_METHODS deploys a version that derives from the same contract, but overrides some methods to use "functionWithSignature" and other variants.

Here's an example:

function testFuzz_deposit_delegate_EXAMPLE(uint24 _random) public {   
    // When new Users are created, they will choose a random configuration from these params.
    // `_randomSeed` will be the starting seed for all random lookups.
    _configRand({
        _randomSeed: _random,
        _assetTypes: HOLDS_LST,
        _userTypes: DEFAULT | ALT_METHODS
    });

    // Because of the `assetTypes` flags above, this will create two Users for our test,
    // each of which holds some random assortment of LSTs.
    (
        User staker,
        IStrategy[] memory strategies, 
        uint[] memory tokenBalances
    ) = _newRandomStaker();
    (User operator, ,) = _newRandomOperator();

    // Because of the `userTypes` flags above, this user might be using either:
    // - `strategyManager.depositIntoStrategy`
    // - `strategyManager.depositIntoStrategyWithSignature`
    staker.depositIntoEigenlayer(strategies, tokenBalances);
    // assertions go here

    // Because of the `userTypes` flags above, this user might be using either:
    // - `delegation.delegateTo`
    // - `delegation.delegateToBySignature`
    staker.delegateTo(operator);
    // assertions go here
}

If you want to know about the time travel, there's a few things to note:

The main feature we're using is foundry's cheats.snapshot() and cheats.revertTo(snapshot) to zip around in time. You can look at the Cheatcodes Reference to get some idea, but the docs aren't actually correct. The best thing to do is look through our tests and see how it's being used. If you see an assertion called assert_Snap_..., that's using the TimeMachine under the hood.

Speaking of, the TimeMachine is a global contract that controls the time, fate, and destiny of all who use it.

• Users use the TimeMachine to snapshot chain state before every action they perform. (see the User.createSnapshot modifier).
• IntegrationBase uses a timewarp modifier to quickly fetch state "from before the last user action". These are leveraged within various assert_Snap_XYZ methods to allow the test to quickly compare previous and current values. (example assertion method)

This means that tests can perform user actions with very little setup or "reading prior state", and perform all the important assertions after each action. For example:

function testFuzz_deposit_delegate_EXAMPLE(uint24 _random) public {   
    // ... test setup goes above here
    
    // This snapshots state before the deposit.
    staker.depositIntoEigenlayer(strategies, tokenBalances);
    // This checks the staker's shares from before `depositIntoEigenlayer`, and compares
    // them to their shares after `depositIntoEigenlayer`.
    assert_Snap_AddedStakerShares(staker, strategies, expectedShares, "failed to award staker shares");

    // This snapshots state before delegating.
    staker.delegateTo(operator);
    // This checks the operator's `operatorShares` before the staker delegated to them, and
    // compares those shares to the `operatorShares` after the staker delegated.
    assert_Snap_AddedOperatorShares(operator, strategies, expectedShares, "failed to award operator shares");
}

Additional Important Concepts

• Most testing logic and checks are performed at the test level. IntegrationBase has primarily helpers and a few sanity checks, but the current structure exists to make it clear what's being tested by reading the test itself.
• Minimal logic/assertions/cheats used in User contract. These are for carrying out user behaviors, only. Exception:
  • User methods snapshot state before performing actions
• Top-level error messages are passed into helper assert methods so that it's always clear where an error came from
• User contract should have an interface as similar as possible to the contract interfaces, so it feels like calling an EigenLayer method rather than some weird abstraction. Exceptions for things like:
  • user.depositIntoEigenLayer(strats, tokenBalances) - because this deposits all strategies/shares and may touch either Smgr or Emgr

What needs to be done?

• Suggest or PR cleanup if you have ideas. Currently, the IntegrationDeployer contract is pretty messy.
• Coordinate in Slack to pick out some user flows to write tests for!