skip calls to hooks when msg.sender is hook contract + test

.forge-snapshots/addLiquidity with empty hook.snap

@@ -1 +1 @@
-311243
+311305

.forge-snapshots/addLiquidity with native token.snap

@@ -1 +1 @@
-191422
+191404

.forge-snapshots/addLiquidity.snap

@@ -1 +1 @@
-191403
+191385

.forge-snapshots/donate gas with 1 token.snap

@@ -1 +1 @@
-131137
+131119

.forge-snapshots/donate gas with 2 tokens.snap

@@ -1 +1 @@
-175960
+175942

.forge-snapshots/poolManager bytecode size.snap

@@ -1 +1 @@
-22875
+22863

.forge-snapshots/removeLiquidity with empty hook.snap

@@ -1 +1 @@
-98020
+98002

.forge-snapshots/removeLiquidity with native token.snap

@@ -1 +1 @@
-199393
+199375

.forge-snapshots/removeLiquidity.snap

@@ -1 +1 @@
-195670
+195652

.forge-snapshots/simple swap with native.snap

@@ -1 +1 @@
-186039
+185948

.forge-snapshots/simple swap.snap

@@ -1 +1 @@
-194579
+194488

.forge-snapshots/swap against liquidity with native token.snap

@@ -1 +1 @@
-116698
+116607

.forge-snapshots/swap against liquidity.snap

@@ -1 +1 @@
-104165
+104074

.forge-snapshots/swap burn 6909 for input.snap

@@ -1 +1 @@
-124314
+124223

.forge-snapshots/swap burn native 6909 for input.snap

@@ -1 +1 @@
-120267
+120176

.forge-snapshots/swap mint native output as 6909.snap

@@ -1 +1 @@
-188597
+188506

.forge-snapshots/swap mint output as 6909.snap

@@ -1 +1 @@
-205406
+205315

.forge-snapshots/swap with dynamic fee.snap

@@ -1 +1 @@
-137470
+137379

.forge-snapshots/swap with hooks.snap

@@ -1 +1 @@
-104143
+104052

.forge-snapshots/update dynamic fee in before swap.snap

@@ -1 +1 @@
-188472
+188421

src/libraries/Hooks.sol

@@ -71,13 +71,13 @@ library Hooks {
     }
 
     /// @notice Ensures that the hook address includes at least one hook flag or dynamic fees, or is the 0 address
-    /// @param hook The hook to verify
-    function isValidHookAddress(IHooks hook, uint24 fee) internal pure returns (bool) {
+    /// @param self The hook to verify
+    function isValidHookAddress(IHooks self, uint24 fee) internal pure returns (bool) {
         // If there is no hook contract set, then fee cannot be dynamic
         // If a hook contract is set, it must have at least 1 flag set, or have a dynamic fee
-        return address(hook) == address(0)
+        return address(self) == address(0)
             ? !fee.isDynamicFee()
-            : (uint160(address(hook)) >= AFTER_DONATE_FLAG || fee.isDynamicFee());
+            : (uint160(address(self)) >= AFTER_DONATE_FLAG || fee.isDynamicFee());
     }
 
     /// @notice performs a hook call using the given calldata on the given hook
@@ -96,6 +96,7 @@ library Hooks {
 
     /// @notice performs a hook call using the given calldata on the given hook
     function callHook(IHooks self, bytes memory data) internal {
+        if (msg.sender == address(self)) return;
         (bytes4 expectedSelector, bytes4 selector) = _callHook(self, data);
 
         if (selector != expectedSelector) {
@@ -132,9 +133,9 @@ library Hooks {
         IPoolManager.ModifyLiquidityParams memory params,
         bytes calldata hookData
     ) internal {
-        if (params.liquidityDelta > 0 && key.hooks.hasPermission(BEFORE_ADD_LIQUIDITY_FLAG)) {
+        if (params.liquidityDelta > 0 && self.hasPermission(BEFORE_ADD_LIQUIDITY_FLAG)) {
             self.callHook(abi.encodeWithSelector(IHooks.beforeAddLiquidity.selector, msg.sender, key, params, hookData));
-        } else if (params.liquidityDelta <= 0 && key.hooks.hasPermission(BEFORE_REMOVE_LIQUIDITY_FLAG)) {
+        } else if (params.liquidityDelta <= 0 && self.hasPermission(BEFORE_REMOVE_LIQUIDITY_FLAG)) {
             self.callHook(
                 abi.encodeWithSelector(IHooks.beforeRemoveLiquidity.selector, msg.sender, key, params, hookData)
             );
@@ -149,11 +150,11 @@ library Hooks {
         BalanceDelta delta,
         bytes calldata hookData
     ) internal {
-        if (params.liquidityDelta > 0 && key.hooks.hasPermission(AFTER_ADD_LIQUIDITY_FLAG)) {
+        if (params.liquidityDelta > 0 && self.hasPermission(AFTER_ADD_LIQUIDITY_FLAG)) {
             self.callHook(
                 abi.encodeWithSelector(IHooks.afterAddLiquidity.selector, msg.sender, key, params, delta, hookData)
             );
-        } else if (params.liquidityDelta <= 0 && key.hooks.hasPermission(AFTER_REMOVE_LIQUIDITY_FLAG)) {
+        } else if (params.liquidityDelta <= 0 && self.hasPermission(AFTER_REMOVE_LIQUIDITY_FLAG)) {
             self.callHook(
                 abi.encodeWithSelector(IHooks.afterRemoveLiquidity.selector, msg.sender, key, params, delta, hookData)
             );
@@ -164,7 +165,7 @@ library Hooks {
     function beforeSwap(IHooks self, PoolKey memory key, IPoolManager.SwapParams memory params, bytes calldata hookData)
         internal
     {
-        if (key.hooks.hasPermission(BEFORE_SWAP_FLAG)) {
+        if (self.hasPermission(BEFORE_SWAP_FLAG)) {
             self.callHook(abi.encodeWithSelector(IHooks.beforeSwap.selector, msg.sender, key, params, hookData));
         }
     }
@@ -177,7 +178,7 @@ library Hooks {
         BalanceDelta delta,
         bytes calldata hookData
     ) internal {
-        if (key.hooks.hasPermission(AFTER_SWAP_FLAG)) {
+        if (self.hasPermission(AFTER_SWAP_FLAG)) {
             self.callHook(abi.encodeWithSelector(IHooks.afterSwap.selector, msg.sender, key, params, delta, hookData));
         }
     }
@@ -186,7 +187,7 @@ library Hooks {
     function beforeDonate(IHooks self, PoolKey memory key, uint256 amount0, uint256 amount1, bytes calldata hookData)
         internal
     {
-        if (key.hooks.hasPermission(BEFORE_DONATE_FLAG)) {
+        if (self.hasPermission(BEFORE_DONATE_FLAG)) {
             self.callHook(
                 abi.encodeWithSelector(IHooks.beforeDonate.selector, msg.sender, key, amount0, amount1, hookData)
             );
@@ -197,7 +198,7 @@ library Hooks {
     function afterDonate(IHooks self, PoolKey memory key, uint256 amount0, uint256 amount1, bytes calldata hookData)
         internal
     {
-        if (key.hooks.hasPermission(AFTER_DONATE_FLAG)) {
+        if (self.hasPermission(AFTER_DONATE_FLAG)) {
             self.callHook(
                 abi.encodeWithSelector(IHooks.afterDonate.selector, msg.sender, key, amount0, amount1, hookData)
             );

src/test/PoolSwapTest.sol

@@ -52,21 +52,16 @@ contract PoolSwapTest is PoolTestBase {
 
         CallbackData memory data = abi.decode(rawData, (CallbackData));
 
-        (,, uint256 reserveBefore0, int256 deltaBefore0) =
-            _fetchBalances(data.key.currency0, data.sender, address(this));
-        (,, uint256 reserveBefore1, int256 deltaBefore1) =
-            _fetchBalances(data.key.currency1, data.sender, address(this));
+        (,,, int256 deltaBefore0) = _fetchBalances(data.key.currency0, data.sender, address(this));
+        (,,, int256 deltaBefore1) = _fetchBalances(data.key.currency1, data.sender, address(this));
 
         require(deltaBefore0 == 0, "deltaBefore0 is not equal to 0");
         require(deltaBefore1 == 0, "deltaBefore1 is not equal to 0");
 
         BalanceDelta delta = manager.swap(data.key, data.params, data.hookData);
 
-        (,, uint256 reserveAfter0, int256 deltaAfter0) = _fetchBalances(data.key.currency0, data.sender, address(this));
-        (,, uint256 reserveAfter1, int256 deltaAfter1) = _fetchBalances(data.key.currency1, data.sender, address(this));
-
-        require(reserveBefore0 == reserveAfter0, "reserveBefore0 is not equal to reserveAfter0");
-        require(reserveBefore1 == reserveAfter1, "reserveBefore1 is not equal to reserveAfter1");
+        (,,, int256 deltaAfter0) = _fetchBalances(data.key.currency0, data.sender, address(this));
+        (,,, int256 deltaAfter1) = _fetchBalances(data.key.currency1, data.sender, address(this));
 
         if (data.params.zeroForOne) {
             if (data.params.amountSpecified < 0) {

src/test/SkipCallsTestHook.sol

@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.24;
+
+import {Hooks} from "../libraries/Hooks.sol";
+import {BaseTestHooks} from "./BaseTestHooks.sol";
+import {IHooks} from "../interfaces/IHooks.sol";
+import {IPoolManager} from "../interfaces/IPoolManager.sol";
+import {PoolKey} from "../types/PoolKey.sol";
+import {BalanceDelta} from "../types/BalanceDelta.sol";
+import {PoolId, PoolIdLibrary} from "../types/PoolId.sol";
+import {IERC20Minimal} from "../interfaces/external/IERC20Minimal.sol";
+import {CurrencyLibrary, Currency} from "../types/Currency.sol";
+import {PoolTestBase} from "./PoolTestBase.sol";
+import {Test} from "forge-std/Test.sol";
+
+contract SkipCallsTestHook is BaseTestHooks, Test {
+    using PoolIdLibrary for PoolKey;
+    using Hooks for IHooks;
+
+    uint256 public counter;
+    IPoolManager manager;
+    uint24 internal fee;
+
+    function setManager(IPoolManager _manager) external {
+        manager = _manager;
+    }
+
+    function beforeSwap(address, PoolKey calldata key, IPoolManager.SwapParams calldata params, bytes calldata hookData)
+        external
+        override
+        returns (bytes4)
+    {
+        counter++;
+        callSwap(key, params, hookData);
+        return IHooks.beforeSwap.selector;
+    }
+
+    function callSwap(PoolKey calldata key, IPoolManager.SwapParams calldata params, bytes calldata hookData) public {
+        IPoolManager(manager).swap(key, params, hookData);
+        address payer = abi.decode(hookData, (address));
+        int256 delta0 = IPoolManager(manager).currencyDelta(address(this), key.currency0);
+        assertEq(delta0, params.amountSpecified);
+        int256 delta1 = IPoolManager(manager).currencyDelta(address(this), key.currency1);
+        assert(delta1 > 0);
+        IERC20Minimal(Currency.unwrap(key.currency0)).transferFrom(payer, address(manager), uint256(-delta0));
+        manager.settle(key.currency0);
+        manager.take(key.currency1, payer, uint256(delta1));
+    }
+}

test/SkipCallsTestHook.t.sol

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.20;
+
+import {Test} from "forge-std/Test.sol";
+import {Vm} from "forge-std/Vm.sol";
+import {PoolId, PoolIdLibrary} from "../src/types/PoolId.sol";
+import {Hooks} from "../src/libraries/Hooks.sol";
+import {SwapFeeLibrary} from "../src/libraries/SwapFeeLibrary.sol";
+import {IPoolManager} from "../src/interfaces/IPoolManager.sol";
+import {IProtocolFees} from "../src/interfaces/IProtocolFees.sol";
+import {IHooks} from "../src/interfaces/IHooks.sol";
+import {PoolKey} from "../src/types/PoolKey.sol";
+import {PoolManager} from "../src/PoolManager.sol";
+import {PoolSwapTest} from "../src/test/PoolSwapTest.sol";
+import {Deployers} from "./utils/Deployers.sol";
+import {GasSnapshot} from "forge-gas-snapshot/GasSnapshot.sol";
+import {Currency, CurrencyLibrary} from "../src/types/Currency.sol";
+import {MockERC20} from "solmate/test/utils/mocks/MockERC20.sol";
+import {Constants} from "../test/utils/Constants.sol";
+import {SkipCallsTestHook} from "../src/test/SkipCallsTestHook.sol";
+
+contract SkipCallsTest is Test, Deployers, GasSnapshot {
+    using PoolIdLibrary for PoolKey;
+
+    SkipCallsTestHook skipCallsTestHook = SkipCallsTestHook(address(uint160(Hooks.BEFORE_SWAP_FLAG)));
+
+    function setUp() public {
+        SkipCallsTestHook impl = new SkipCallsTestHook();
+        vm.etch(address(skipCallsTestHook), address(impl).code);
+        deployFreshManagerAndRouters();
+        skipCallsTestHook.setManager(IPoolManager(manager));
+
+        (currency0, currency1) = deployMintAndApprove2Currencies();
+        (key,) = initPoolAndAddLiquidity(
+            currency0, currency1, IHooks(address(skipCallsTestHook)), 3000, SQRT_RATIO_1_1, ZERO_BYTES
+        );
+    }
+
+    function test_beforeSwap_skipIfCalledByHook() public {
+        IPoolManager.SwapParams memory swapParams =
+            IPoolManager.SwapParams({zeroForOne: true, amountSpecified: -100, sqrtPriceLimitX96: SQRT_RATIO_1_2});
+
+        PoolSwapTest.TestSettings memory testSettings =
+            PoolSwapTest.TestSettings({withdrawTokens: true, settleUsingTransfer: true, currencyAlreadySent: false});
+
+        MockERC20(Currency.unwrap(key.currency0)).approve(address(skipCallsTestHook), Constants.MAX_UINT256);
+
+        assertEq(skipCallsTestHook.counter(), 0);
+        swapRouter.swap(key, swapParams, testSettings, abi.encode(address(this)));
+        assertEq(skipCallsTestHook.counter(), 1);
+    }
+}