Q-AJN-8: Old Version of Solidity

- update pragmas to 0.8.18
- use preverando instead difficulty (need a version of foundry containing foundry-rs/foundry#4856)

.github/workflows/slither.yml

@@ -26,7 +26,7 @@ jobs:
 
       - name: Analyze GrantFund
         run: |
-          solc-select install 0.8.16 && solc-select use 0.8.16
+          solc-select install 0.8.18 && solc-select use 0.8.18
           slither src/grants/
         continue-on-error: true
         id: fund_analyzer

script/GrantFund.s.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { Script }  from "forge-std/Script.sol";
 import { console } from "forge-std/console.sol";

src/grants/GrantFund.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IERC20 }    from "@oz/token/ERC20/IERC20.sol";
 import { SafeERC20 } from "@oz/token/ERC20/utils/SafeERC20.sol";

src/grants/base/ExtraordinaryFunding.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IERC20 }   from "@oz/token/ERC20/IERC20.sol";
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";

src/grants/base/Funding.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { Address }         from "@oz/utils/Address.sol";
 import { IVotes }          from "@oz/governance/utils/IVotes.sol";

src/grants/base/StandardFunding.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IERC20 }    from "@oz/token/ERC20/IERC20.sol";
 import { SafeCast }  from "@oz/utils/math/SafeCast.sol";

src/grants/interfaces/IExtraordinaryFunding.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 
 //slither-disable-next-line solc-version
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 /**
  * @title Ajna Grant Coordination Fund Extraordinary Proposal flow.

src/grants/interfaces/IFunding.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 
 //slither-disable-next-line solc-version
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 /**
  * @title Ajna Grant Coordination Fund Extraordinary Proposal flow.

src/grants/interfaces/IGrantFund.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IFunding } from "../interfaces/IFunding.sol";
 import { IExtraordinaryFunding } from "../interfaces/IExtraordinaryFunding.sol";

src/grants/interfaces/IStandardFunding.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 
 //slither-disable-next-line solc-version
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 /**
  * @title Ajna Grant Coordination Fund Standard Proposal flow.

src/grants/libraries/Maths.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 library Maths {
 

test/interactions/DrainGrantFund.sol

@@ -1,4 +1,4 @@
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IExtraordinaryFunding } from "src/grants/interfaces/IExtraordinaryFunding.sol";
 import { IAjnaToken }            from "../utils/IAjnaToken.sol";

test/invariants/ExtraordinaryInvariant.t.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console }  from "@std/console.sol";
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";

test/invariants/StandardFinalizeInvariant.t.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console }  from "@std/console.sol";
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";

test/invariants/StandardFundingInvariant.t.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console }  from "@std/console.sol";
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";

test/invariants/StandardMultipleDistributionInvariant.t.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console }  from "@std/console.sol";
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";

test/invariants/StandardScreeningInvariant.t.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console } from "@std/console.sol";
 

test/invariants/base/ExtraordinaryTestBase.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console } from "@std/console.sol";
 

test/invariants/base/ITestBase.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: UNLICENSED
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 interface ITestBase {
 

test/invariants/base/StandardTestBase.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console } from "@std/console.sol";
 

test/invariants/base/TestBase.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { Test }   from "@std/Test.sol";
 

test/invariants/handlers/ExtraordinaryHandler.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console }  from "@std/console.sol";
 import { Test }     from "forge-std/Test.sol";

test/invariants/handlers/Handler.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { Test }    from "forge-std/Test.sol";
 import { Strings } from "@oz/utils/Strings.sol";
@@ -200,7 +200,7 @@ contract Handler is Test, GrantFundTestHelper {
 
     function randomSeed() internal returns (uint256) {
         counter++;
-        return uint256(keccak256(abi.encodePacked(block.number, block.difficulty, counter)));
+        return uint256(keccak256(abi.encodePacked(block.number, block.prevrandao, counter)));
     }
 
     function getActorsCount() public view returns(uint256) {

test/invariants/handlers/StandardHandler.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { console } from "@std/console.sol";
 import { Test }     from "forge-std/Test.sol";

test/unit/ExtraordinaryFunding.t.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { GrantFund }             from "../../src/grants/GrantFund.sol";
 import { IExtraordinaryFunding } from "../../src/grants/interfaces/IExtraordinaryFunding.sol";

test/unit/GrantFund.t.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { GrantFund }           from "../../src/grants/GrantFund.sol";
 import { IFunding }            from "../../src/grants/interfaces/IFunding.sol";

test/unit/Maths.t.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { Test } from "@std/Test.sol";
 

test/unit/StandardFunding.t.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { SafeCast }  from "@oz/utils/math/SafeCast.sol";
 

test/utils/GrantFundTestHelper.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { SafeCast } from "@oz/utils/math/SafeCast.sol";
 import { Strings }  from "@oz/utils/Strings.sol"; // used for createNProposals
@@ -367,7 +367,7 @@ abstract contract GrantFundTestHelper is Test {
     // Returns a random proposal Index from all proposals
     function _getRandomProposal(uint256 noOfProposals_) internal returns(uint256 proposal_) {
         // calculate random proposal Index between 0 and noOfProposals_
-        proposal_ = uint256(keccak256(abi.encodePacked(block.number, block.difficulty))) % noOfProposals_;
+        proposal_ = uint256(keccak256(abi.encodePacked(block.number, block.prevrandao))) % noOfProposals_;
         vm.roll(block.number + 1);
     }
 
@@ -476,7 +476,7 @@ abstract contract GrantFundTestHelper is Test {
             descriptionPartTwo = string.concat(descriptionPartTwo, ", ");
 
             // generate a random nonce to add to the description string to avoid collisions
-            uint256 randomNonce = uint256(keccak256(abi.encodePacked(block.number, block.difficulty))) % 100;
+            uint256 randomNonce = uint256(keccak256(abi.encodePacked(block.number, block.prevrandao))) % 100;
             descriptionPartTwo = string.concat(descriptionPartTwo, Strings.toString(randomNonce));
         }
         description_ = string(abi.encodePacked(descriptionPartOne, descriptionPartTwo));
@@ -661,7 +661,7 @@ abstract contract GrantFundTestHelper is Test {
     // Returns random votes for a user
     function _randomVote() internal returns (uint256 votes_) {
         // calculate random vote between 1 and 1.25 * 1e18
-        votes_ = 1 + uint256(keccak256(abi.encodePacked(block.number, block.difficulty))) % (1.25 * 1e18);
+        votes_ = 1 + uint256(keccak256(abi.encodePacked(block.number, block.prevrandao))) % (1.25 * 1e18);
         vm.roll(block.number + 1);
     }
 

test/utils/IAjnaToken.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity 0.8.16;
+pragma solidity 0.8.18;
 
 import { IVotes }    from "@oz/governance/utils/IVotes.sol";
 import { IERC20 }      from "@oz/token/ERC20/IERC20.sol";