Update Solc version from 0.8.18 to 0.8.24

contracts/hardhat.config.ts

@@ -21,7 +21,7 @@ dotenv.config();
 
 const config: HardhatUserConfig = {
   solidity: {
-    version: "0.8.18",
+    version: "0.8.24",
     settings: {
       optimizer: {
         enabled: true,

contracts/package.json

@@ -64,7 +64,7 @@
     "@nomicfoundation/hardhat-chai-matchers": "^1.0.6",
     "@nomiclabs/hardhat-ethers": "^2.2.3",
     "@nomiclabs/hardhat-solhint": "^3.0.1",
-    "@openzeppelin/contracts": "^4.9.5",
+    "@openzeppelin/contracts": "^5.0.2",
     "@typechain/ethers-v5": "^11.1.2",
     "@typechain/hardhat": "^7.0.0",
     "@types/chai": "^4.3.11",
@@ -98,6 +98,6 @@
     "typescript": "^5.3.3"
   },
   "dependencies": {
-    "@kleros/vea-contracts": "^0.3.2"
+    "@kleros/vea-contracts": "^0.4.0"
   }
 }

contracts/src/arbitration/CentralizedArbitrator.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {IArbitrableV2, IArbitratorV2, IERC20} from "./interfaces/IArbitratorV2.sol";
 
@@ -29,9 +29,9 @@ contract CentralizedArbitrator is IArbitratorV2 {
     }
 
     struct Round {
-        mapping(uint256 => uint256) paidFees; // Tracks the fees paid for each choice in this round.
-        mapping(uint256 => bool) hasPaid; // True if this choice was fully funded, false otherwise.
-        mapping(address => mapping(uint256 => uint256)) contributions; // Maps contributors to their contributions for each choice.
+        mapping(uint256 choiceId => uint256) paidFees; // Tracks the fees paid for each choice in this round.
+        mapping(uint256 choiceId => bool) hasPaid; // True if this choice was fully funded, false otherwise.
+        mapping(address account => mapping(uint256 choiceId => uint256)) contributions; // Maps contributors to their contributions for each choice.
         uint256 feeRewards; // Sum of reimbursable appeal fees available to the parties that made contributions to the ruling that ultimately wins a dispute.
         uint256[] fundedChoices; // Stores the choices that are fully funded.
     }

contracts/src/arbitration/DisputeTemplateRegistry.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../proxy/UUPSProxiable.sol";
 import "../proxy/Initializable.sol";

contracts/src/arbitration/KlerosCore.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./KlerosCoreBase.sol";
 import {UUPSProxiable} from "../proxy/UUPSProxiable.sol";

contracts/src/arbitration/KlerosCoreBase.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {IArbitrableV2, IArbitratorV2} from "./interfaces/IArbitratorV2.sol";
 import {IDisputeKit} from "./interfaces/IDisputeKit.sol";
@@ -41,7 +41,7 @@ abstract contract KlerosCoreBase is IArbitratorV2 {
         uint256 feeForJuror; // Arbitration fee paid per juror.
         uint256 jurorsForCourtJump; // The appeal after the one that reaches this number of jurors will go to the parent court if any.
         uint256[4] timesPerPeriod; // The time allotted to each dispute period in the form `timesPerPeriod[period]`.
-        mapping(uint256 => bool) supportedDisputeKits; // True if DK with this ID is supported by the court. Note that each court must support classic dispute kit.
+        mapping(uint256 disputeKitId => bool) supportedDisputeKits; // True if DK with this ID is supported by the court. Note that each court must support classic dispute kit.
         bool disabled; // True if the court is disabled. Unused for now, will be implemented later.
     }
 

contracts/src/arbitration/KlerosCoreNeo.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./KlerosCoreBase.sol";
 import {UUPSProxiable} from "../proxy/UUPSProxiable.sol";

contracts/src/arbitration/KlerosGovernor.sol

@@ -5,7 +5,7 @@
 /// @custom:auditors: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {IArbitrableV2, IArbitratorV2} from "./interfaces/IArbitrableV2.sol";
 import "./interfaces/IDisputeTemplateRegistry.sol";
@@ -31,7 +31,7 @@ contract KlerosGovernor is IArbitrableV2 {
         uint256[] submittedLists; // Tracks all lists that were submitted in a session in the form submittedLists[submissionID].
         uint256 sumDeposit; // Sum of all submission deposits in a session (minus arbitration fees). This is used to calculate the reward.
         Status status; // Status of a session.
-        mapping(bytes32 => bool) alreadySubmitted; // Indicates whether or not the transaction list was already submitted in order to catch duplicates in the form alreadySubmitted[listHash].
+        mapping(bytes32 listHash => bool) alreadySubmitted; // Indicates whether or not the transaction list was already submitted in order to catch duplicates in the form alreadySubmitted[listHash].
         uint256 durationOffset; // Time in seconds that prolongs the submission period after the first submission, to give other submitters time to react.
     }
 

contracts/src/arbitration/PolicyRegistry.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../proxy/UUPSProxiable.sol";
 import "../proxy/Initializable.sol";

contracts/src/arbitration/SortitionModule.sol

@@ -8,7 +8,7 @@
  *  @custom:deployments: []
  */
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./SortitionModuleBase.sol";
 import "../proxy/UUPSProxiable.sol";

contracts/src/arbitration/SortitionModuleBase.sol

@@ -8,7 +8,7 @@
  *  @custom:deployments: []
  */
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./KlerosCore.sol";
 import "./interfaces/ISortitionModule.sol";
@@ -70,10 +70,10 @@ abstract contract SortitionModuleBase is ISortitionModule {
     uint256 public rngLookahead; // Minimal block distance between requesting and obtaining a random number.
     uint256 public delayedStakeWriteIndex; // The index of the last `delayedStake` item that was written to the array. 0 index is skipped.
     uint256 public delayedStakeReadIndex; // The index of the next `delayedStake` item that should be processed. Starts at 1 because 0 index is skipped.
-    mapping(bytes32 => SortitionSumTree) sortitionSumTrees; // The mapping trees by keys.
-    mapping(address => Juror) public jurors; // The jurors.
+    mapping(bytes32 treeHash => SortitionSumTree) sortitionSumTrees; // The mapping trees by keys.
+    mapping(address account => Juror) public jurors; // The jurors.
     mapping(uint256 => DelayedStake) public delayedStakes; // Stores the stakes that were changed during Drawing phase, to update them when the phase is switched to Staking.
-    mapping(address => mapping(uint96 => uint256)) public latestDelayedStakeIndex; // Maps the juror to its latest delayed stake. If there is already a delayed stake for this juror then it'll be replaced. latestDelayedStakeIndex[juror][courtID].
+    mapping(address jurorAccount => mapping(uint96 courtId => uint256)) public latestDelayedStakeIndex; // Maps the juror to its latest delayed stake. If there is already a delayed stake for this juror then it'll be replaced. latestDelayedStakeIndex[juror][courtID].
 
     // ************************************* //
     // *              Events               * //

contracts/src/arbitration/SortitionModuleNeo.sol

@@ -8,7 +8,7 @@
  *  @custom:deployments: []
  */
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./SortitionModuleBase.sol";
 import "../proxy/UUPSProxiable.sol";

contracts/src/arbitration/arbitrables/ArbitrableExample.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {IArbitrableV2, IArbitratorV2} from "../interfaces/IArbitrableV2.sol";
 import "../interfaces/IDisputeTemplateRegistry.sol";

contracts/src/arbitration/arbitrables/DisputeResolver.sol

@@ -8,7 +8,7 @@
 import {IArbitrableV2, IArbitratorV2} from "../interfaces/IArbitrableV2.sol";
 import "../interfaces/IDisputeTemplateRegistry.sol";
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 /// @title DisputeResolver
 /// DisputeResolver contract adapted for V2 from https://github.com/kleros/arbitrable-proxy-contracts/blob/master/contracts/ArbitrableProxy.sol.

contracts/src/arbitration/dispute-kits/DisputeKitClassic.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../KlerosCore.sol";
 import "../interfaces/IDisputeKit.sol";
@@ -39,9 +39,9 @@ contract DisputeKitClassic is IDisputeKit, Initializable, UUPSProxiable {
         bool tied; // True if there is a tie, false otherwise.
         uint256 totalVoted; // Former uint[_appeal] votesInEachRound.
         uint256 totalCommitted; // Former commitsInRound.
-        mapping(uint256 => uint256) paidFees; // Tracks the fees paid for each choice in this round.
-        mapping(uint256 => bool) hasPaid; // True if this choice was fully funded, false otherwise.
-        mapping(address => mapping(uint256 => uint256)) contributions; // Maps contributors to their contributions for each choice.
+        mapping(uint256 choiceId => uint256) paidFees; // Tracks the fees paid for each choice in this round.
+        mapping(uint256 choiceId => bool) hasPaid; // True if this choice was fully funded, false otherwise.
+        mapping(address account => mapping(uint256 choiceId => uint256)) contributions; // Maps contributors to their contributions for each choice.
         uint256 feeRewards; // Sum of reimbursable appeal fees available to the parties that made contributions to the ruling that ultimately wins a dispute.
         uint256[] fundedChoices; // Stores the choices that are fully funded.
         uint256 nbVotes; // Maximal number of votes this dispute can get.

contracts/src/arbitration/dispute-kits/DisputeKitSybilResistant.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../KlerosCore.sol";
 import "../interfaces/IDisputeKit.sol";
@@ -46,13 +46,13 @@ contract DisputeKitSybilResistant is IDisputeKit, Initializable, UUPSProxiable {
         bool tied; // True if there is a tie, false otherwise.
         uint256 totalVoted; // Former uint[_appeal] votesInEachRound.
         uint256 totalCommitted; // Former commitsInRound.
-        mapping(uint256 => uint256) paidFees; // Tracks the fees paid for each choice in this round.
-        mapping(uint256 => bool) hasPaid; // True if this choice was fully funded, false otherwise.
-        mapping(address => mapping(uint256 => uint256)) contributions; // Maps contributors to their contributions for each choice.
+        mapping(uint256 choiceId => uint256) paidFees; // Tracks the fees paid for each choice in this round.
+        mapping(uint256 choiceId => bool) hasPaid; // True if this choice was fully funded, false otherwise.
+        mapping(address account => mapping(uint256 choiceId => uint256)) contributions; // Maps contributors to their contributions for each choice.
         uint256 feeRewards; // Sum of reimbursable appeal fees available to the parties that made contributions to the ruling that ultimately wins a dispute.
         uint256[] fundedChoices; // Stores the choices that are fully funded.
         uint256 nbVotes; // Maximal number of votes this dispute can get.
-        mapping(address => bool) alreadyDrawn; // Set to 'true' if the address has already been drawn, so it can't be drawn more than once.
+        mapping(address drawnAddress => bool) alreadyDrawn; // Set to 'true' if the address has already been drawn, so it can't be drawn more than once.
     }
 
     struct Vote {

contracts/src/arbitration/evidence/EvidenceModule.sol

@@ -7,7 +7,7 @@
 /// @custom:deployments: []
 /// @custom:tools: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../interfaces/IArbitratorV2.sol";
 import "../interfaces/IEvidence.sol";

contracts/src/arbitration/evidence/ModeratedEvidenceModule.sol

@@ -7,7 +7,7 @@
 /// @custom:deployments: []
 /// @custom:tools: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 // TODO: standard interfaces should be placed in a separated repo (?)
 import {IArbitrableV2, IArbitratorV2} from "../interfaces/IArbitrableV2.sol";
@@ -39,7 +39,7 @@ contract ModeratedEvidenceModule is IArbitrableV2 {
     struct Moderation {
         uint256[3] paidFees; // Tracks the fees paid by each side in this moderation.
         uint256 feeRewards; // Sum of reimbursable fees and stake rewards available to the parties that made contributions to the side that ultimately wins a dispute.
-        mapping(address => uint256[3]) contributions; // Maps contributors to their contributions for each side.
+        mapping(address contributor => uint256[3]) contributions; // Maps contributors to their contributions for each side.
         bool closed; // Moderation happens over a bounded period of time after which it is considered closed. If so, a new moderation round should be opened.
         Party currentWinner; // The current winner of this moderation round.
         uint256 bondDeadline; // The deadline until which the loser party can stake to overturn the current status.
@@ -57,7 +57,7 @@ contract ModeratedEvidenceModule is IArbitrableV2 {
 
     uint256 public constant AMOUNT_OF_CHOICES = 2;
     uint256 public constant MULTIPLIER_DIVISOR = 10000; // Divisor parameter for multipliers.
-    mapping(bytes32 => EvidenceData) evidences; // Maps the evidence ID to its data. evidences[evidenceID].
+    mapping(bytes32 evidenceId => EvidenceData) evidences; // Maps the evidence ID to its data. evidences[evidenceID].
     mapping(uint256 => bytes32) public disputeIDtoEvidenceID; // One-to-one relationship between the dispute and the evidence.
     ArbitratorData[] public arbitratorDataList; // Stores the arbitrator data of the contract. Updated each time the data is changed.
     IArbitratorV2 public immutable arbitrator; // The trusted arbitrator to resolve potential disputes. If it needs to be changed, a new contract can be deployed.

contracts/src/arbitration/interfaces/IArbitrableV2.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./IArbitratorV2.sol";
 

contracts/src/arbitration/interfaces/IArbitratorV2.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import "./IArbitrableV2.sol";

contracts/src/arbitration/interfaces/IDisputeKit.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./IArbitratorV2.sol";
 

contracts/src/arbitration/interfaces/IDisputeTemplateRegistry.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 /// @title IDisputeTemplate
 /// @notice Dispute Template interface.

contracts/src/arbitration/interfaces/IEvidence.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 /// @title IEvidence
 interface IEvidence {

contracts/src/arbitration/interfaces/ISortitionModule.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../../libraries/Constants.sol";
 

contracts/src/arbitration/university/ISortitionModuleUniversity.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {ISortitionModule} from "../interfaces/ISortitionModule.sol";
 

contracts/src/arbitration/university/KlerosCoreUniversity.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import {IArbitrableV2, IArbitratorV2} from "../interfaces/IArbitratorV2.sol";
 import {IDisputeKit} from "../interfaces/IDisputeKit.sol";
@@ -36,7 +36,7 @@ contract KlerosCoreUniversity is IArbitratorV2, UUPSProxiable, Initializable {
         uint256 feeForJuror; // Arbitration fee paid per juror.
         uint256 jurorsForCourtJump; // The appeal after the one that reaches this number of jurors will go to the parent court if any.
         uint256[4] timesPerPeriod; // The time allotted to each dispute period in the form `timesPerPeriod[period]`.
-        mapping(uint256 => bool) supportedDisputeKits; // True if DK with this ID is supported by the court. Note that each court must support classic dispute kit.
+        mapping(uint256 disputeKitId => bool) supportedDisputeKits; // True if DK with this ID is supported by the court. Note that each court must support classic dispute kit.
         bool disabled; // True if the court is disabled. Unused for now, will be implemented later.
     }
 

contracts/src/arbitration/university/SortitionModuleUniversity.sol

@@ -8,7 +8,7 @@
  *  @custom:deployments: []
  */
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./KlerosCoreUniversity.sol";
 import "./ISortitionModuleUniversity.sol";
@@ -38,7 +38,7 @@ contract SortitionModuleUniversity is ISortitionModuleUniversity, UUPSProxiable,
     address public governor; // The governor of the contract.
     KlerosCoreUniversity public core; // The core arbitrator contract.
     uint256 public disputesWithoutJurors; // The number of disputes that have not finished drawing jurors.
-    mapping(address => Juror) public jurors; // The jurors.
+    mapping(address account => Juror) public jurors; // The jurors.
     address private transientJuror; // The juror address used between calls within the same transaction.
 
     // ************************************* //

contracts/src/gateway/ForeignGateway.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./interfaces/IForeignGateway.sol";
 import "../proxy/UUPSProxiable.sol";
@@ -39,14 +39,14 @@ contract ForeignGateway is IForeignGateway, UUPSProxiable, Initializable {
     // ************************************* //
 
     uint256 internal localDisputeID; // The disputeID must start from 1 as the KlerosV1 proxy governor depends on this implementation. We now also depend on localDisputeID not ever being zero.
-    mapping(uint96 => uint256) public feeForJuror; // feeForJuror[v2CourtID], it mirrors the value on KlerosCore.
+    mapping(uint96 courtId => uint256) public feeForJuror; // feeForJuror[v2CourtID], it mirrors the value on KlerosCore.
     address public governor;
     address public veaOutbox;
     uint256 public override homeChainID;
     address public override homeGateway;
     address public deprecatedVeaOutbox;
     uint256 public deprecatedVeaOutboxExpiration;
-    mapping(bytes32 => DisputeData) public disputeHashtoDisputeData;
+    mapping(bytes32 disputeHash => DisputeData) public disputeHashtoDisputeData;
 
     // ************************************* //
     // *        Function Modifiers         * //

contracts/src/gateway/HomeGateway.sol

@@ -6,7 +6,7 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "./interfaces/IForeignGateway.sol";
 import "./interfaces/IHomeGateway.sol";

contracts/src/gateway/interfaces/IForeignGateway.sol

@@ -6,10 +6,10 @@
 /// @custom:bounties: []
 /// @custom:deployments: []
 
-pragma solidity 0.8.18;
+pragma solidity 0.8.24;
 
 import "../../arbitration/interfaces/IArbitratorV2.sol";
-import "@kleros/vea-contracts/src/interfaces/gateways/IReceiverGateway.sol";
+import "@kleros/vea-contracts/interfaces/gateways/IReceiverGateway.sol";
 
 interface IForeignGateway is IArbitratorV2, IReceiverGateway {
     /// @dev To be emitted when a dispute is sent to the IHomeGateway.