Merge pull request #236 from RealityETH/forkableRealityETHUsingCreate…

…Children

Made forkable reality.eth inherit from @reality.eth/contracts and fork using ForkableStructure

contracts/L1ForkArbitrator.sol

@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+pragma solidity ^0.8.20;
+
+/*
+This is a very limited Arbitrator contract for the purpose of handling an arbitration request and passing it on to the ForkingManager.
+It doesn't handle submitting the answer to the winning question, this is instead handled by the child reality.eth contract when forking.
+*/
+
+import {IRealityETH} from "@reality.eth/contracts/development/contracts/IRealityETH.sol";
+import {IArbitratorCore} from "@reality.eth/contracts/development/contracts/IArbitratorCore.sol";
+import {IArbitratorErrors} from "@reality.eth/contracts/development/contracts/IArbitratorErrors.sol";
+import {IForkingManager} from "./interfaces/IForkingManager.sol";
+import {IForkonomicToken} from "./interfaces/IForkonomicToken.sol";
+import {IForkableStructure} from "./interfaces/IForkableStructure.sol";
+
+contract L1ForkArbitrator is IArbitratorCore, IArbitratorErrors {
+    IForkingManager public forkmanager;
+    IRealityETH public realitio;
+    IForkonomicToken public token;
+
+    /// @notice Could not approve the transfer for some reason
+    error CouldNotApproveTransfer();
+
+    /// @notice Could not deduct fee
+    error CouldNotDeductFee();
+
+    /// @notice Not forked yet
+    error NotForkedYet();
+
+    /// @notice This arbitrator can only arbitrate one dispute in its lifetime
+    error CanOnlyArbitrateOneDispute();
+
+    /// @notice The question ID must be supplied
+    error MissingQuestionID();
+
+    bytes32 public arbitratingQuestionId;
+    address public payer;
+
+    constructor(address _realitio, address _forkmanager, address _token) {
+        realitio = IRealityETH(_realitio);
+        forkmanager = IForkingManager(_forkmanager);
+        token = IForkonomicToken(_token);
+    }
+
+    /* solhint-disable quotes */
+    // Tells the UI to know that it should prompt the user to use ERC20 instead of the native token.
+    string public metadata = '{"erc20": true}';
+
+    /// @notice Return the dispute fee for the specified question. 0 indicates that we won't arbitrate it.
+    /// @dev Uses a general default, but can be over-ridden on a question-by-question basis.
+    function getDisputeFee(bytes32) public view returns (uint256) {
+        return forkmanager.arbitrationFee();
+    }
+
+    /// @notice Request arbitration, freezing the question until we send submitAnswerByArbitrator
+    /// @dev Requires payment in token(), which the UI as of early 2024 will not handle.
+    /// @param _questionId The question in question
+    /// @param _maxPrevious If specified, reverts if a bond higher than this was submitted after you sent your transaction.
+    /// NB TODO: This is payable because the interface expects native tokens. Consider changing the interface or adding an ERC20 version.
+    function requestArbitration(
+        bytes32 _questionId,
+        uint256 _maxPrevious
+    ) external payable returns (bool) {
+        if (arbitratingQuestionId != bytes32(0))
+            revert CanOnlyArbitrateOneDispute();
+        if (_questionId == bytes32(0)) revert MissingQuestionID();
+
+        uint256 fee = getDisputeFee(_questionId);
+        if (fee == 0)
+            revert TheArbitratorMustHaveSetANonZeroFeeForTheQuestion();
+
+        // First we transfer the fee to ourselves.
+        if (!token.transferFrom(msg.sender, address(this), fee))
+            revert CouldNotDeductFee();
+
+        payer = msg.sender;
+        arbitratingQuestionId = _questionId;
+
+        realitio.notifyOfArbitrationRequest(
+            _questionId,
+            msg.sender,
+            _maxPrevious
+        );
+
+        // Now approve so that the fee can be transferred right out to the ForkingManager
+        if (!token.approve(address(forkmanager), fee))
+            revert CouldNotApproveTransfer();
+        IForkingManager.DisputeData memory disputeData = IForkingManager
+            .DisputeData(true, address(this), _questionId);
+        IForkingManager(forkmanager).initiateFork(disputeData);
+
+        return true;
+    }
+
+    function settleChildren(
+        bytes32 lastHistoryHash,
+        bytes32 lastAnswer,
+        address lastAnswerer
+    ) public {
+        (address child1, address child2) = IForkableStructure(address(realitio))
+            .getChildren();
+        if (child1 == address(0) || child2 == address(0)) revert NotForkedYet();
+        IRealityETH(child1).assignWinnerAndSubmitAnswerByArbitrator(
+            arbitratingQuestionId,
+            bytes32(uint256(1)),
+            payer,
+            lastHistoryHash,
+            lastAnswer,
+            lastAnswerer
+        );
+        IRealityETH(child2).assignWinnerAndSubmitAnswerByArbitrator(
+            arbitratingQuestionId,
+            bytes32(uint256(0)),
+            payer,
+            lastHistoryHash,
+            lastAnswer,
+            lastAnswerer
+        );
+    }
+}

contracts/interfaces/IForkableRealityETH_ERC20.sol

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+pragma solidity ^0.8.20;
+
+import {IRealityETH_ERC20} from "@reality.eth/contracts/development/contracts/IRealityETH_ERC20.sol";
+
+// solhint-disable-next-line contract-name-camelcase
+interface IForkableRealityETH_ERC20 is IRealityETH_ERC20 {
+    function creditBalanceFromParent(
+        address beneficiary,
+        uint256 amount
+    ) external;
+    function l1ForkArbitrator() external returns (address);
+}

contracts/interfaces/IForkingManager.sol

@@ -36,7 +36,7 @@ interface IForkingManager is IForkableStructure {
 
     function globalExitRoot() external returns (address);
 
-    function arbitrationFee() external returns (uint256);
+    function arbitrationFee() external view returns (uint256);
 
     function disputeData()
         external

package.json

@@ -47,6 +47,7 @@
     "@openzeppelin/contracts": "^4.9.5",
     "@openzeppelin/contracts-upgradeable": "^4.9.5",
     "@openzeppelin/hardhat-upgrades": "1.22.1",
+    "@reality.eth/contracts": "4.0.0-rc.5",
     "@RealityETH/zkevm-contracts": "github:RealityETH/zkevm-contracts#a090458140cdfce23763af887ff0767469368923",
     "@types/sinon-chai": "^3.2.3",
     "circomlibjs": "0.1.1",

remappings.txt

@@ -1,2 +1,2 @@
 ds-test/=lib/forge-std/lib/ds-test/src/
-forge-std/=lib/forge-std/src/
+forge-std/=lib/forge-std/src/

test/AdjudicationFramework/AdjudicationFrameworkMinimal.t.sol

@@ -128,7 +128,12 @@ contract AdjudicationIntegrationTest is Test {
         );
 
         l1RealityEth = new ForkableRealityETH_ERC20();
-        l1RealityEth.init(tokenMock, address(0), bytes32(0));
+        l1RealityEth.initialize(
+            address(l1ForkingManager),
+            address(0),
+            address(tokenMock),
+            bytes32(0)
+        );
 
         /*
         Creates templates 1, 2, 3 as

test/AdjudicationFramework/AdjudicationFrameworkRequests.t.sol

@@ -127,7 +127,12 @@ contract AdjudicationIntegrationTest is Test {
         );
 
         l1RealityEth = new ForkableRealityETH_ERC20();
-        l1RealityEth.init(tokenMock, address(0), bytes32(0));
+        l1RealityEth.initialize(
+            address(l1ForkingManager),
+            address(0),
+            address(tokenMock),
+            (0)
+        );
 
         /*
         Creates templates 1, 2, 3 as