feat(contracts/solve): most recent request per status (#2675)

Added `getLatestRequestByStatus(status)`, which retrieves the most
recent request to be set to a particular status. I also replaced the
`deployedAt` Arbitrum branch handling with something much more robust.

I attempted to add `getRequestUpdateHistory(id)`, which would return the
timestamp history for all status updates a request has undergone.
Despite this not altering the request and fulfillment flows, it broke
the e2e tests, so this has been excluded for now.

issue: #2679

contracts/solve/.gas-snapshot

@@ -1,33 +1,33 @@
-SolveInbox_accept_Test:test_accept_one_request() (gas: 395276)
-SolveInbox_accept_Test:test_accept_reverts() (gas: 1047031)
-SolveInbox_accept_Test:test_accept_skip_first() (gas: 703186)
-SolveInbox_accept_Test:test_accept_two_requests() (gas: 727312)
-SolveInbox_cancel_Test:test_cancel_multiToken() (gas: 548512)
-SolveInbox_cancel_Test:test_cancel_nativeMultiToken() (gas: 637552)
-SolveInbox_cancel_Test:test_cancel_oldest_request() (gas: 693948)
-SolveInbox_cancel_Test:test_cancel_one_request() (gas: 396173)
-SolveInbox_cancel_Test:test_cancel_rejected_nativeMultiToken_request() (gas: 647058)
-SolveInbox_cancel_Test:test_cancel_rejected_nativeToken_request() (gas: 405192)
-SolveInbox_cancel_Test:test_cancel_reverts() (gas: 1068135)
-SolveInbox_cancel_Test:test_cancel_singleToken() (gas: 427717)
-SolveInbox_cancel_Test:test_cancel_two_requests() (gas: 705726)
-SolveInbox_claim_Test:test_claim_multiDeposit() (gas: 719118)
-SolveInbox_claim_Test:test_claim_reverts() (gas: 448858)
-SolveInbox_claim_Test:test_claim_singleNative() (gas: 471334)
-SolveInbox_claim_Test:test_claim_singleToken() (gas: 502256)
-SolveInbox_markFulfilled_Test:test_markFulfilled_reverts() (gas: 506937)
-SolveInbox_markFulfilled_Test:test_markFulfilled_success() (gas: 417277)
-SolveInbox_reject_Test:test_reject_nativeMultiToken() (gas: 601341)
-SolveInbox_reject_Test:test_reject_oldest_request() (gas: 666353)
-SolveInbox_reject_Test:test_reject_one_request() (gas: 368071)
-SolveInbox_reject_Test:test_reject_reverts() (gas: 749056)
-SolveInbox_reject_Test:test_reject_two_requests() (gas: 670691)
-SolveInbox_request_Test:test_request_multiToken() (gas: 551270)
-SolveInbox_request_Test:test_request_nativeMultiToken() (gas: 609471)
-SolveInbox_request_Test:test_request_reverts() (gas: 929951)
-SolveInbox_request_Test:test_request_singleNative() (gas: 369998)
-SolveInbox_request_Test:test_request_singleToken() (gas: 431512)
-SolveInbox_request_Test:test_request_two() (gas: 678931)
+SolveInbox_accept_Test:test_accept_one_request() (gas: 449411)
+SolveInbox_accept_Test:test_accept_reverts() (gas: 1135399)
+SolveInbox_accept_Test:test_accept_skip_first() (gas: 757442)
+SolveInbox_accept_Test:test_accept_two_requests() (gas: 781616)
+SolveInbox_cancel_Test:test_cancel_multiToken() (gas: 604009)
+SolveInbox_cancel_Test:test_cancel_nativeMultiToken() (gas: 694160)
+SolveInbox_cancel_Test:test_cancel_oldest_request() (gas: 758515)
+SolveInbox_cancel_Test:test_cancel_one_request() (gas: 450572)
+SolveInbox_cancel_Test:test_cancel_rejected_nativeMultiToken_request() (gas: 738004)
+SolveInbox_cancel_Test:test_cancel_rejected_nativeToken_request() (gas: 491782)
+SolveInbox_cancel_Test:test_cancel_reverts() (gas: 1157387)
+SolveInbox_cancel_Test:test_cancel_singleToken() (gas: 482102)
+SolveInbox_cancel_Test:test_cancel_two_requests() (gas: 760517)
+SolveInbox_claim_Test:test_claim_multiDeposit() (gas: 819751)
+SolveInbox_claim_Test:test_claim_reverts() (gas: 537428)
+SolveInbox_claim_Test:test_claim_singleNative() (gas: 569792)
+SolveInbox_claim_Test:test_claim_singleToken() (gas: 600715)
+SolveInbox_markFulfilled_Test:test_markFulfilled_reverts() (gas: 551134)
+SolveInbox_markFulfilled_Test:test_markFulfilled_success() (gas: 493564)
+SolveInbox_reject_Test:test_reject_nativeMultiToken() (gas: 657806)
+SolveInbox_reject_Test:test_reject_oldest_request() (gas: 730802)
+SolveInbox_reject_Test:test_reject_one_request() (gas: 422363)
+SolveInbox_reject_Test:test_reject_reverts() (gas: 815736)
+SolveInbox_reject_Test:test_reject_two_requests() (gas: 725273)
+SolveInbox_request_Test:test_request_multiToken() (gas: 584500)
+SolveInbox_request_Test:test_request_nativeMultiToken() (gas: 643788)
+SolveInbox_request_Test:test_request_reverts() (gas: 1018635)
+SolveInbox_request_Test:test_request_singleNative() (gas: 402136)
+SolveInbox_request_Test:test_request_singleToken() (gas: 463652)
+SolveInbox_request_Test:test_request_two() (gas: 711209)
 SolveOutbox_fulfill_test:test_fulfillFee() (gas: 27996)
 SolveOutbox_fulfill_test:test_fulfill_reverts() (gas: 673377)
 SolveOutbox_fulfill_test:test_fulfill_succeeds() (gas: 274856)

contracts/solve/src/Solve.sol

@@ -34,6 +34,7 @@ library Solve {
      * @param status        Request status (open, accepted, cancelled, rejected, fulfilled, paid).
      * @param call          Details of the call to be executed on another chain.
      * @param deposits      Array of deposits backing the request.
+     * @param updateHistory Array of status updates including timestamps.
      */
     struct Request {
         bytes32 id;

contracts/solve/src/SolveInbox.sol

@@ -69,11 +69,23 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
      */
     mapping(bytes32 id => Solve.Request) internal _requests;
 
+    /**
+     * @notice Map status to latest request ID.
+     */
+    mapping(Solve.Status => bytes32 id) internal _latestReqByStatus;
+
     constructor() {
         // Must get Arbitrum block number from ArbSys precompile, block.number returns L1 block number on Arbitrum.
-        // This is a temporary fix, we need a robust way of properly setting this value when on any Arbitrum chain.
-        if (block.chainid != 42_161 && block.chainid != 421_614) deployedAt = block.number;
-        else deployedAt = IArbSys(ARB_SYS).arbBlockNumber();
+        if (_isContract(ARB_SYS)) {
+            try IArbSys(ARB_SYS).arbBlockNumber() returns (uint256 arbBlockNumber) {
+                deployedAt = arbBlockNumber;
+            } catch {
+                deployedAt = block.number;
+            }
+        } else {
+            deployedAt = block.number;
+        }
+
         _disableInitializers();
     }
 
@@ -97,6 +109,13 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         return _requests[id];
     }
 
+    /**
+     * @notice Returns the latest request with the given status.
+     */
+    function getLatestRequestByStatus(Solve.Status status) external view returns (Solve.Request memory) {
+        return _requests[_latestReqByStatus[status]];
+    }
+
     /**
      * @notice Open a request to execute a call on another chain, backed by deposits.
      *  Token deposits are transferred from msg.sender to this inbox.
@@ -134,6 +153,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.status = Solve.Status.Accepted;
         req.acceptedBy = msg.sender;
 
+        _latestReqByStatus[Solve.Status.Accepted] = id;
+
         emit Accepted(id, msg.sender);
     }
 
@@ -149,6 +170,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.updatedAt = uint40(block.timestamp);
         req.status = Solve.Status.Rejected;
 
+        _latestReqByStatus[Solve.Status.Rejected] = id;
+
         emit Rejected(id, msg.sender, reason);
     }
 
@@ -165,6 +188,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.updatedAt = uint40(block.timestamp);
         req.status = Solve.Status.Reverted;
 
+        _latestReqByStatus[Solve.Status.Reverted] = id;
+
         _transferDeposits(req.from, req.deposits);
 
         emit Reverted(id);
@@ -186,6 +211,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.updatedAt = uint40(block.timestamp);
         req.status = Solve.Status.Fulfilled;
 
+        _latestReqByStatus[Solve.Status.Fulfilled] = id;
+
         emit Fulfilled(id, callHash, req.acceptedBy);
     }
 
@@ -202,6 +229,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.updatedAt = uint40(block.timestamp);
         req.status = Solve.Status.Claimed;
 
+        _latestReqByStatus[Solve.Status.Claimed] = id;
+
         _transferDeposits(to, req.deposits);
 
         emit Claimed(id, msg.sender, to, req.deposits);
@@ -241,6 +270,8 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
         req.from = from;
         req.call = call;
 
+        _latestReqByStatus[Solve.Status.Pending] = id;
+
         if (msg.value > 0) {
             req.deposits.push(Solve.Deposit({ isNative: true, token: address(0), amount: msg.value }));
         }
@@ -271,4 +302,15 @@ contract SolveInbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase, I
     function _callHash(bytes32 id, uint64 sourceChainId, Solve.Call storage call) internal pure returns (bytes32) {
         return keccak256(abi.encode(id, sourceChainId, call));
     }
+
+    /**
+     * @dev Returns true if the address is a contract.
+     */
+    function _isContract(address addr) internal view returns (bool) {
+        uint32 size;
+        assembly {
+            size := extcodesize(addr)
+        }
+        return (size > 0);
+    }
 }

contracts/solve/src/SolveOutbox.sol

@@ -85,9 +85,16 @@ contract SolveOutbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase {
 
     constructor() {
         // Must get Arbitrum block number from ArbSys precompile, block.number returns L1 block number on Arbitrum.
-        // This is a temporary fix, we need a robust way of properly setting this value when on any Arbitrum chain.
-        if (block.chainid != 42_161 && block.chainid != 421_614) deployedAt = block.number;
-        else deployedAt = IArbSys(ARB_SYS).arbBlockNumber();
+        if (_isContract(ARB_SYS)) {
+            try IArbSys(ARB_SYS).arbBlockNumber() returns (uint256 arbBlockNumber) {
+                deployedAt = arbBlockNumber;
+            } catch {
+                deployedAt = block.number;
+            }
+        } else {
+            deployedAt = block.number;
+        }
+
         _disableInitializers();
     }
 
@@ -185,4 +192,15 @@ contract SolveOutbox is OwnableRoles, ReentrancyGuard, Initializable, XAppBase {
     function _callHash(bytes32 srcReqId, uint64 srcChainId, Solve.Call calldata call) internal pure returns (bytes32) {
         return keccak256(abi.encode(srcReqId, srcChainId, call));
     }
+
+    /**
+     * @dev Returns true if the address is a contract.
+     */
+    function _isContract(address addr) internal view returns (bool) {
+        uint32 size;
+        assembly {
+            size := extcodesize(addr)
+        }
+        return (size > 0);
+    }
 }

contracts/solve/src/interfaces/ISolveInbox.sol

@@ -56,6 +56,11 @@ interface ISolveInbox {
      */
     function getRequest(bytes32 id) external view returns (Solve.Request memory);
 
+    /**
+     * @notice Returns the latest request with the given status.
+     */
+    function getLatestRequestByStatus(Solve.Status status) external view returns (Solve.Request memory);
+
     /**
      * @notice Open a request to execute a call on another chain, backed by deposits.
      *  Token deposits are transferred from msg.sender to this inbox.

contracts/solve/test/Inbox_accept.t.sol

@@ -81,6 +81,11 @@ contract SolveInbox_accept_Test is InboxBase {
 
         assertEq(inbox.getRequest(id).acceptedBy, solver, "inbox.getRequest(id).acceptedBy");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Accepted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Accepted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Accepted)"
+        );
     }
 
     /// @dev Test accepting two requests
@@ -104,6 +109,11 @@ contract SolveInbox_accept_Test is InboxBase {
         assertEq(inbox.getRequest(id2).acceptedBy, solver, "inbox.getRequest(id2).acceptedBy");
         assertEq(uint8(inbox.getRequest(id1).status), uint8(Solve.Status.Accepted), "inbox.getRequest(id1).status");
         assertEq(uint8(inbox.getRequest(id2).status), uint8(Solve.Status.Accepted), "inbox.getRequest(id2).status");
+        assertEq(
+            id2,
+            inbox.getLatestRequestByStatus(Solve.Status.Accepted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Accepted)"
+        );
     }
 
     /// @dev Test accepting requests out of order
@@ -126,5 +136,10 @@ contract SolveInbox_accept_Test is InboxBase {
         assertEq(inbox.getRequest(id2).acceptedBy, solver, "inbox.getRequest(id2).acceptedBy");
         assertEq(uint8(inbox.getRequest(id1).status), uint8(Solve.Status.Pending), "inbox.getRequest(id1).status");
         assertEq(uint8(inbox.getRequest(id2).status), uint8(Solve.Status.Accepted), "inbox.getRequest(id2).status");
+        assertEq(
+            id2,
+            inbox.getLatestRequestByStatus(Solve.Status.Accepted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Accepted)"
+        );
     }
 }

contracts/solve/test/Inbox_cancel.t.sol

@@ -75,6 +75,11 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(address(inbox).balance, 0, "address(inbox).balance");
         assertEq(address(user).balance, 1 ether, "address(user).balance");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_two_requests() public {
@@ -97,6 +102,11 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(address(user).balance, 2 ether, "address(user).balance");
         assertEq(uint8(inbox.getRequest(id1).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id1).status");
         assertEq(uint8(inbox.getRequest(id2).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id2).status");
+        assertEq(
+            id2,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_oldest_request() public {
@@ -117,6 +127,16 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(address(user).balance, 1 ether, "address(user).balance");
         assertEq(uint8(inbox.getRequest(id1).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id1).status");
         assertEq(uint8(inbox.getRequest(id2).status), uint8(Solve.Status.Pending), "inbox.getRequest(id2).status");
+        assertEq(
+            id1,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
+        assertEq(
+            id2,
+            inbox.getLatestRequestByStatus(Solve.Status.Pending).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Pending)"
+        );
     }
 
     function test_cancel_singleToken() public {
@@ -136,6 +156,11 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(token1.balanceOf(address(inbox)), 0, "token1.balanceOf(inbox)");
         assertEq(token1.balanceOf(user), 1 ether, "token1.balanceOf(user)");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_multiToken() public {
@@ -158,6 +183,11 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(token1.balanceOf(user), 1 ether, "token1.balanceOf(user)");
         assertEq(token2.balanceOf(user), 1 ether, "token2.balanceOf(user)");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_nativeMultiToken() public {
@@ -183,6 +213,11 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(token1.balanceOf(user), 1 ether, "token1.balanceOf(user)");
         assertEq(token2.balanceOf(user), 1 ether, "token2.balanceOf(user)");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_rejected_nativeToken_request() public {
@@ -204,6 +239,16 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(address(inbox).balance, 0, "address(inbox).balance");
         assertEq(address(user).balance, 1 ether, "address(user).balance");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Rejected).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Rejected)"
+        );
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 
     function test_cancel_rejected_nativeMultiToken_request() public {
@@ -233,5 +278,15 @@ contract SolveInbox_cancel_Test is InboxBase {
         assertEq(token1.balanceOf(user), 1 ether, "token1.balanceOf(user)");
         assertEq(token2.balanceOf(user), 1 ether, "token2.balanceOf(user)");
         assertEq(uint8(inbox.getRequest(id).status), uint8(Solve.Status.Reverted), "inbox.getRequest(id).status");
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Rejected).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Rejected)"
+        );
+        assertEq(
+            id,
+            inbox.getLatestRequestByStatus(Solve.Status.Reverted).id,
+            "inbox.getLatestRequestByStatus(Solve.Status.Reverted)"
+        );
     }
 }