tests: add solver delegate coverage

.env.example

@@ -0,0 +1,7 @@
+ETH_MAINNET_RPC_URL=
+GNOSIS_RPC_URL=
+ARBITRUM_ONE_RPC_URL=
+BASE_RPC_URL=
+OPTIMISM_RPC_URL=
+POLYGON_RPC_URL=
+BNB_MAINNET_RPC_URL=

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "lib/forge-std"]
 	path = lib/forge-std
 	url = https://github.com/foundry-rs/forge-std
+[submodule "lib/openzeppelin-contracts"]
+	path = lib/openzeppelin-contracts
+	url = https://github.com/OpenZeppelin/openzeppelin-contracts

Justfile

@@ -60,15 +60,15 @@ slither:
 
 # Run tests
 test:
-    {{FORGE}} test -vvv --show-progress --gas-snapshot-check true
+    {{FORGE}} test -vvv --show-progress
 
 # Print coverage summary
 coverage-summary:
-    {{FORGE}} coverage --no-match-coverage "^(test|script)/" --report summary
+    {{FORGE}} coverage --no-match-coverage "^(test|script|lib)/" --report summary
 
 # Generate lcov coverage report
 coverage-lcov:
-    {{FORGE}} coverage --no-match-coverage "^(test|script)/" --report lcov
+    {{FORGE}} coverage --no-match-coverage "^(test|script|lib)/" --report lcov
 
 # Fail if the minimum of all four coverage metrics (lines/statements/branches/funcs) on the `Total` row is below `COVERAGE_MIN` (default `100`)
 coverage-check:

foundry.lock

@@ -1,5 +1,11 @@
 {
   "lib/forge-std": {
     "rev": "1801b0541f4fda118a10798fd3486bb7051c5dd6"
+  },
+  "lib/openzeppelin-contracts": {
+    "tag": {
+      "name": "v5.6.1",
+      "rev": "5fd1781b1454fd1ef8e722282f86f9293cacf256"
+    }
   }
 }

foundry.toml

@@ -2,6 +2,9 @@
 src = "src"
 out = "out"
 libs = ["lib"]
+remappings = [
+    "@openzeppelin/contracts/=lib/openzeppelin-contracts/contracts/"
+]
 solc = "0.8.34" # See latest release at: https://github.com/argotorg/solidity/releases
 
 [fmt]
@@ -13,4 +16,4 @@ wrap_comments = true
 deny = "warnings" # Why not always: sometimes you just want to code and see what comes out
 verbosity = 3 # Outputs stack traces for failed tests.
 fuzz.seed = "0"
-fuzz.runs = 10_000
+fuzz.runs = 10_000

snapshots/Solver7702DelegateForkTest.json

@@ -0,0 +1,26 @@
+{
+  "arbitrum - delegated call - simple WETH -> USDC order attempt": "15439",
+  "arbitrum - direct call - simple WETH -> USDC order attempt": "11450",
+  "base - delegated call - simple WETH -> USDC order attempt": "15435",
+  "base - direct call - simple WETH -> USDC order attempt": "11450",
+  "bnb - delegated call - simple WETH -> USDC order attempt": "15439",
+  "bnb - direct call - simple WETH -> USDC order attempt": "11450",
+  "ethereum - delegated call - simple WETH -> USDC order attempt": "15439",
+  "ethereum - direct call - simple WETH -> USDC order attempt": "11450",
+  "gnosis - delegated call - simple WETH -> USDC order attempt": "15439",
+  "gnosis - direct call - simple WETH -> USDC order attempt": "11450",
+  "historical order - delegated call - USDC -> EURA": "190342",
+  "historical order - delegated call - USDC permit -> MOG": "446987",
+  "historical order - delegated call - USDT -> AAVE": "783398",
+  "historical order - delegated call - WETH -> USDC": "253863",
+  "historical order - delegated call - YFI -> USDC": "814546",
+  "historical order - direct call - USDC -> EURA": "186425",
+  "historical order - direct call - USDC permit -> MOG": "443150",
+  "historical order - direct call - USDT -> AAVE": "779746",
+  "historical order - direct call - WETH -> USDC": "249951",
+  "historical order - direct call - YFI -> USDC": "811173",
+  "optimism - delegated call - simple WETH -> USDC order attempt": "15439",
+  "optimism - direct call - simple WETH -> USDC order attempt": "11450",
+  "polygon - delegated call - simple WETH -> USDC order attempt": "15439",
+  "polygon - direct call - simple WETH -> USDC order attempt": "11450"
+}

snapshots/Solver7702DelegateIntegrationTest.json

@@ -0,0 +1,9 @@
+{
+  "delegated submission - reverts - UnauthorizedCaller": "460",
+  "delegated submission - success - interactions across phases": "44776",
+  "delegated submission - success - large settlement with interactions": "114722",
+  "delegated submission - success - small settlement": "24184",
+  "direct submission - success - interactions across phases": "157450",
+  "direct submission - success - large settlement with interactions": "224869",
+  "direct submission - success - small settlement": "117371"
+}

snapshots/Solver7702DelegateTest.json

@@ -0,0 +1,21 @@
+{
+  "constructor - success - distinct callers": "1212494",
+  "constructor - success - duplicate callers": "1212494",
+  "constructor - success - zero address callers": "1212494",
+  "delegate fallback - reverts - custom error": "4398",
+  "delegate fallback - reverts - empty revert data": "3753",
+  "delegate fallback - reverts - non-empty revert data": "3828",
+  "delegate fallback - reverts - panic": "3405",
+  "delegate fallback - reverts - sending ETH to nonpayable target": "9875",
+  "delegate fallback - reverts - string error": "4057",
+  "delegate fallback - reverts - unauthorized caller": "460",
+  "delegate fallback - success - approved caller slot 0 forwards payload": "43084",
+  "delegate fallback - success - approved caller slot 1 forwards payload": "23429",
+  "delegate fallback - success - approved caller slot 2 forwards payload": "23490",
+  "delegate fallback - success - approved caller slot 3 forwards payload": "23549",
+  "delegate fallback - success - approved caller slot 4 forwards payload": "23577",
+  "delegate fallback - success - packed calldata bubbles return data": "3767",
+  "delegate fallback - success - packed calldata forwards zero ETH": "23749",
+  "delegate fallback - success - target has no code": "3131",
+  "delegate fallback - success - target is zero address": "631"
+}

src/Solver7702Delegate.sol

@@ -34,6 +34,7 @@ contract Solver7702Delegate {
     }
 
     /// @notice Fallback function to handle calls to the delegate
+    /// @dev Expected calldata format is `bytes20(target) || targetCalldata`.
     fallback() external payable {
         // Simply receive ETH
         if (msg.data.length < 20) return;

test/.solhint.json

@@ -1,6 +1,8 @@
 {
   "rules": {
     "func-name-mixedcase": "off",
+    "gas-strict-inequalities": "off",
+    "no-empty-blocks": "off",
     "use-natspec": "off"
   }
 }

test/BaseTest.t.sol

@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
+pragma solidity ^0.8.34;
+
+import {Test} from "forge-std/Test.sol";
+
+import {Solver7702Delegate} from "src/Solver7702Delegate.sol";
+
+struct ApprovedCallers {
+    /// @notice First approved caller slot.
+    address first;
+    /// @notice Second approved caller slot.
+    address second;
+    /// @notice Third approved caller slot.
+    address third;
+    /// @notice Fourth approved caller slot.
+    address fourth;
+    /// @notice Fifth approved caller slot.
+    address fifth;
+}
+
+/// @notice Shared setup and helpers for Solver7702Delegate tests.
+abstract contract BaseTest is Test {
+    /// @notice Private key for the EOA that gets EIP-7702 delegation attached.
+    uint256 internal constant SOLVER_PRIVATE_KEY = uint256(keccak256("SOLVER_PRIVATE_KEY"));
+    /// @notice ETH value used by tests that forward native token value.
+    uint256 internal constant MSG_VALUE = 1 ether;
+    /// @notice Number of bytes used to encode the packed target address.
+    uint256 internal constant PACKED_TARGET_LENGTH = 20;
+    /// @notice Shared token and mock settlement amount.
+    uint256 internal constant TEST_AMOUNT = 100 ether;
+    /// @notice Shared order UID used by mock settlement tests.
+    bytes32 internal constant TEST_ORDER_UID = keccak256("TEST_ORDER_UID");
+    /// @notice Selector for RawRevert(uint256,string).
+    bytes4 internal constant RAW_REVERT_SELECTOR = bytes4(keccak256("RawRevert(uint256,string)"));
+
+    /// @notice Shared solver address.
+    address internal solver;
+    /// @notice Shared recipient address.
+    address internal recipient;
+    /// @notice Shared unauthorized caller address.
+    address internal unauthorizedCaller;
+    /// @notice Shared approved callers.
+    ApprovedCallers internal approvedCallers;
+    /// @notice Shared delegate contract.
+    Solver7702Delegate internal delegateContract;
+
+    /// @notice Creates the default solver, approved callers, and delegate contract.
+    function setUp() public virtual {
+        solver = vm.addr(SOLVER_PRIVATE_KEY);
+        recipient = makeAddr("RECIPIENT");
+        unauthorizedCaller = makeAddr("UNAUTHORIZED_CALLER");
+        approvedCallers = ApprovedCallers({
+            first: makeAddr("APPROVED_CALLER_0"),
+            second: makeAddr("APPROVED_CALLER_1"),
+            third: makeAddr("APPROVED_CALLER_2"),
+            fourth: makeAddr("APPROVED_CALLER_3"),
+            fifth: makeAddr("APPROVED_CALLER_4")
+        });
+
+        delegateContract = new Solver7702Delegate(
+            [
+                approvedCallers.first,
+                approvedCallers.second,
+                approvedCallers.third,
+                approvedCallers.fourth,
+                approvedCallers.fifth
+            ]
+        );
+    }
+
+    /// @notice Encodes the delegate fallback calldata as a 20-byte target followed by payload.
+    function _packedCalldata(address target, bytes memory payload) internal pure returns (bytes memory) {
+        return abi.encodePacked(bytes20(target), payload);
+    }
+
+    /// @notice Attaches the delegate code to the solver EOA.
+    function _attachDelegation(uint256 solverPrivateKey) internal {
+        vm.signAndAttachDelegation(address(delegateContract), solverPrivateKey);
+    }
+
+    /// @notice Decodes and checks the return data from PayableFallbackTarget.
+    function _assertFallbackReturn(
+        bytes memory returnData,
+        address expectedSender,
+        uint256 expectedValue,
+        bytes memory expectedPayload,
+        uint256 expectedBalance
+    ) internal pure {
+        (address sender, uint256 value, bytes memory payload, uint256 balance) =
+            abi.decode(returnData, (address, uint256, bytes, uint256));
+
+        assertEq(sender, expectedSender);
+        assertEq(value, expectedValue);
+        assertEq(payload, expectedPayload);
+        assertEq(balance, expectedBalance);
+    }
+}