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Assertion

Git Source

Inherits: Credible, StateChanges

Title: Assertion

Author: Phylax Systems

Base contract for creating Credible Layer assertions

Inherit from this contract to create custom assertions. Assertions can inspect transaction state via the inherited ph precompile and register triggers to specify when the assertion should be executed. Example:

contract MyAssertion is Assertion {
function triggers() external view override {
registerCallTrigger(this.checkInvariant.selector, ITarget.deposit.selector);
}
function checkInvariant() external {
ph.forkPostTx();
Check invariants...
}
}

State Variables

triggerRecorder

The trigger recorder precompile for registering assertion triggers

Address is derived from a deterministic hash for consistency

TriggerRecorder constant triggerRecorder = TriggerRecorder(address(uint160(uint256(keccak256("TriggerRecorder")))))

Functions

triggers

Used to record fn selectors and their triggers.

function triggers() external view virtual;

registerCallTrigger

Registers a call trigger for the AA without specifying an AA function selector. This will trigger the assertion function on any call to the AA.

function registerCallTrigger(bytes4 fnSelector) internal view;

Parameters

NameTypeDescription
fnSelectorbytes4The function selector of the assertion function.

registerCallTrigger

Registers a call trigger for calls to the AA with a specific AA function selector.

function registerCallTrigger(bytes4 fnSelector, bytes4 triggerSelector) internal view;

Parameters

NameTypeDescription
fnSelectorbytes4The function selector of the assertion function.
triggerSelectorbytes4The function selector upon which the assertion will be triggered.

registerStorageChangeTrigger

Registers storage change trigger for any slot

function registerStorageChangeTrigger(bytes4 fnSelector) internal view;

Parameters

NameTypeDescription
fnSelectorbytes4The function selector of the assertion function.

registerStorageChangeTrigger

Registers storage change trigger for a specific slot

function registerStorageChangeTrigger(bytes4 fnSelector, bytes32 slot) internal view;

Parameters

NameTypeDescription
fnSelectorbytes4The function selector of the assertion function.
slotbytes32The storage slot to trigger on.

registerBalanceChangeTrigger

Registers balance change trigger for the AA

function registerBalanceChangeTrigger(bytes4 fnSelector) internal view;

Parameters

NameTypeDescription
fnSelectorbytes4The function selector of the assertion function.