Dynamic after fee mock + test base

foundry.toml

@@ -5,6 +5,7 @@ libs            = ['lib']                               # A list of library dire
 optimizer       = true                                  # Enable or disable the solc optimizer
 optimizer_runs  = 200                                   # The number of optimizer runs
 fs_permissions  = [{ access = "read", path = "./"}]     # Gives permission to read files for deployment keys.
+evm_version     = "cancun"                              # The EVM version to use
 
 [fuzz]
 runs           = 100        # The number of times to run the fuzzing tests

src/base/DynamicAfterFee.sol

@@ -11,7 +11,7 @@ import {IPoolManager} from "v4-core/src/interfaces/IPoolManager.sol";
 import {BeforeSwapDelta} from "v4-core/src/types/BeforeSwapDelta.sol";
 
 abstract contract DynamicAfterFee is BaseHook {
-    mapping(PoolId => BalanceDelta) private _targetDeltas;
+    mapping(PoolId => BalanceDelta) internal _targetDeltas;
 
     constructor(IPoolManager _poolManager) BaseHook(_poolManager) {}
 

test/DynamicAfterFee.t.sol

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import {Test} from "forge-std/Test.sol";
+import {Deployers} from "v4-core/test/utils/Deployers.sol";
+import {DynamicAfterFeeMock} from "test/mocks/DynamicAfterFeeMock.sol";
+import {IHooks} from "v4-core/src/interfaces/IHooks.sol";
+import {Hooks} from "v4-core/src/libraries/Hooks.sol";
+import {PoolSwapTest} from "v4-core/src/test/PoolSwapTest.sol";
+import {IPoolManager} from "v4-core/src/interfaces/IPoolManager.sol";
+import {Currency} from "v4-core/src/types/Currency.sol";
+import {BalanceDelta} from "v4-core/src/types/BalanceDelta.sol";
+import {PoolKey} from "v4-core/src/types/PoolKey.sol";
+import {LPFeeLibrary} from "v4-core/src/libraries/LPFeeLibrary.sol";
+
+contract DynamicAfterFeeTest is Test, Deployers {
+    DynamicAfterFeeMock hook;
+    PoolKey noHookKey;
+
+    function setUp() public {
+        deployFreshManagerAndRouters();
+        deployMintAndApprove2Currencies();
+
+        hook = DynamicAfterFeeMock(
+            address(uint160(Hooks.BEFORE_SWAP_FLAG | Hooks.AFTER_SWAP_FLAG | Hooks.AFTER_SWAP_RETURNS_DELTA_FLAG))
+        );
+        deployCodeTo("test/mocks/DynamicAfterFeeMock.sol:DynamicAfterFeeMock", abi.encode(manager), address(hook));
+
+        (key,) = initPoolAndAddLiquidity(
+            currency0, currency1, IHooks(address(hook)), LPFeeLibrary.DYNAMIC_FEE_FLAG, SQRT_PRICE_1_1
+        );
+        (noHookKey,) = initPoolAndAddLiquidity(currency0, currency1, IHooks(address(0)), 100, SQRT_PRICE_1_1);
+
+        vm.label(Currency.unwrap(currency0), "currency0");
+        vm.label(Currency.unwrap(currency1), "currency1");
+    }
+}

test/mocks/DynamicAfterFeeMock.sol

@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import "src/base/DynamicAfterFee.sol";
+import {BeforeSwapDeltaLibrary} from "v4-core/src/types/BeforeSwapDelta.sol";
+import {BalanceDelta} from "v4-core/src/types/BalanceDelta.sol";
+
+contract DynamicAfterFeeMock is DynamicAfterFee {
+    constructor(IPoolManager _poolManager) DynamicAfterFee(_poolManager) {}
+
+    function _beforeSwap(address, PoolKey calldata key, IPoolManager.SwapParams calldata params, bytes calldata)
+        internal
+        override
+        returns (bytes4, BeforeSwapDelta, uint24)
+    {
+        PoolId poolId = key.toId();
+        _targetDeltas[poolId] = BalanceDelta.wrap(0);
+
+        return (this.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
+    }
+
+    function getHookPermissions() public pure virtual override returns (Hooks.Permissions memory) {
+        return Hooks.Permissions({
+            beforeInitialize: false,
+            afterInitialize: false,
+            beforeAddLiquidity: false,
+            afterAddLiquidity: false,
+            beforeRemoveLiquidity: false,
+            afterRemoveLiquidity: false,
+            beforeSwap: true,
+            afterSwap: true,
+            beforeDonate: false,
+            afterDonate: false,
+            beforeSwapReturnDelta: false,
+            afterSwapReturnDelta: true,
+            afterAddLiquidityReturnDelta: false,
+            afterRemoveLiquidityReturnDelta: false
+        });
+    }
+}