v4-core/test/libraries/Lock.t.sol

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

import {Test} from "forge-std/Test.sol";
import {Lock} from "../../src/libraries/Lock.sol";

contract LockTest is Test {
    function test_lock() public {
        assertFalse(Lock.isUnlocked());

        Lock.unlock();

        assertTrue(Lock.isUnlocked());

        Lock.lock();

        assertFalse(Lock.isUnlocked());
    }

    function test_unlockedSlot() public pure {
        assertEq(bytes32(uint256(keccak256("Unlocked")) - 1), Lock.IS_UNLOCKED_SLOT);
    }
}