Fix linter errors

.solhint.json

@@ -12,6 +12,7 @@
         "not-rely-on-time": "off",
         "reason-string": "off",
         "no-empty-blocks": "off",
-        "avoid-low-level-calls": "off"
+        "avoid-low-level-calls": "off",
+        "custom-errors": "off"
     }
 }

contracts/Safe.sol

@@ -1,17 +1,18 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
 
-import "./base/ModuleManager.sol";
-import "./base/OwnerManager.sol";
-import "./base/FallbackManager.sol";
-import "./base/GuardManager.sol";
-import "./common/NativeCurrencyPaymentFallback.sol";
-import "./common/Singleton.sol";
-import "./common/SignatureDecoder.sol";
-import "./common/SecuredTokenTransfer.sol";
-import "./common/StorageAccessible.sol";
-import "./interfaces/ISignatureValidator.sol";
-import "./external/SafeMath.sol";
+import {Guard} from "./base/GuardManager.sol";
+import {ModuleManager} from "./base/ModuleManager.sol";
+import {OwnerManager} from "./base/OwnerManager.sol";
+import {FallbackManager} from "./base/FallbackManager.sol";
+import {NativeCurrencyPaymentFallback} from "./common/NativeCurrencyPaymentFallback.sol";
+import {Singleton} from "./common/Singleton.sol";
+import {SignatureDecoder} from "./common/SignatureDecoder.sol";
+import {SecuredTokenTransfer} from "./common/SecuredTokenTransfer.sol";
+import {StorageAccessible} from "./common/StorageAccessible.sol";
+import {Enum} from "./common/Enum.sol";
+import {ISignatureValidator, ISignatureValidatorConstants} from "./interfaces/ISignatureValidator.sol";
+import {SafeMath} from "./external/SafeMath.sol";
 
 /**
  * @title Safe - A multisignature wallet with support for confirmations using signed messages based on EIP-712.
@@ -307,21 +308,23 @@ contract Safe is
 
                 // Check if the contract signature is in bounds: start of data is s + 32 and end is start + signature length
                 uint256 contractSignatureLen;
-                // solhint-disable-next-line no-inline-assembly
+                /* solhint-disable no-inline-assembly */
                 /// @solidity memory-safe-assembly
                 assembly {
                     contractSignatureLen := mload(add(add(signatures, s), 0x20))
                 }
+                /* solhint-enable no-inline-assembly */
                 require(uint256(s).add(32).add(contractSignatureLen) <= signatures.length, "GS023");
 
                 // Check signature
                 bytes memory contractSignature;
-                // solhint-disable-next-line no-inline-assembly
+                /* solhint-disable no-inline-assembly */
                 /// @solidity memory-safe-assembly
                 assembly {
                     // The signature data for contract signatures is appended to the concatenated signatures and the offset is stored in s
                     contractSignature := add(add(signatures, s), 0x20)
                 }
+                /* solhint-enable no-inline-assembly */
                 require(ISignatureValidator(currentOwner).isValidSignature(dataHash, contractSignature) == EIP1271_MAGIC_VALUE, "GS024");
             } else if (v == 1) {
                 // If v is 1 then it is an approved hash
@@ -361,11 +364,12 @@ contract Safe is
      */
     function domainSeparator() public view returns (bytes32) {
         uint256 chainId;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             chainId := chainid()
         }
+        /* solhint-enable no-inline-assembly */
 
         return keccak256(abi.encode(DOMAIN_SEPARATOR_TYPEHASH, chainId, this));
     }

contracts/SafeL2.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
 
-import "./Safe.sol";
+import {Safe, Enum} from "./Safe.sol";
 
 /**
  * @title SafeL2 - An implementation of the Safe contract that emits additional events on transaction executions.

contracts/accessors/SimulateTxAccessor.sol

@@ -1,26 +1,26 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
 
-import "../base/Executor.sol";
+import {Executor, Enum} from "../base/Executor.sol";
 
 /**
  * @title Simulate Transaction Accessor.
  * @notice Can be used with StorageAccessible to simulate Safe transactions.
  * @author Richard Meissner - @rmeissner
  */
 contract SimulateTxAccessor is Executor {
-    address private immutable accessorSingleton;
+    address private immutable ACCESSOR_SINGLETON;
 
     constructor() {
-        accessorSingleton = address(this);
+        ACCESSOR_SINGLETON = address(this);
     }
 
     /**
      * @notice Modifier to make a function callable via delegatecall only.
      * If the function is called via a regular call, it will revert.
      */
     modifier onlyDelegateCall() {
-        require(address(this) != accessorSingleton, "SimulateTxAccessor should only be called via delegatecall");
+        require(address(this) != ACCESSOR_SINGLETON, "SimulateTxAccessor should only be called via delegatecall");
         _;
     }
 
@@ -48,7 +48,7 @@ contract SimulateTxAccessor is Executor {
         uint256 startGas = gasleft();
         success = execute(to, value, data, operation, gasleft());
         estimate = startGas - gasleft();
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             // Load free memory location
@@ -63,5 +63,6 @@ contract SimulateTxAccessor is Executor {
             // Point the return data to the correct memory location
             returnData := ptr
         }
+        /* solhint-enable no-inline-assembly */
     }
 }

contracts/base/Executor.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
-import "../common/Enum.sol";
+import {Enum} from "../common/Enum.sol";
 
 /**
  * @title Executor - A contract that can execute transactions
@@ -26,17 +26,19 @@ abstract contract Executor {
         uint256 txGas
     ) internal returns (bool success) {
         if (operation == Enum.Operation.DelegateCall) {
-            // solhint-disable-next-line no-inline-assembly
+            /* solhint-disable no-inline-assembly */
             /// @solidity memory-safe-assembly
             assembly {
                 success := delegatecall(txGas, to, add(data, 0x20), mload(data), 0, 0)
             }
+            /* solhint-enable no-inline-assembly */
         } else {
-            // solhint-disable-next-line no-inline-assembly
+            /* solhint-disable no-inline-assembly */
             /// @solidity memory-safe-assembly
             assembly {
                 success := call(txGas, to, value, add(data, 0x20), mload(data), 0, 0)
             }
+            /* solhint-enable no-inline-assembly */
         }
     }
 }

contracts/base/FallbackManager.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
 
-import "../common/SelfAuthorized.sol";
+import {SelfAuthorized} from "../common/SelfAuthorized.sol";
 
 /**
  * @title Fallback Manager - A contract managing fallback calls made to this contract
@@ -34,11 +34,12 @@ abstract contract FallbackManager is SelfAuthorized {
         require(handler != address(this), "GS400");
 
         bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             sstore(slot, handler)
         }
+        /* solhint-enable no-inline-assembly */
     }
 
     /**
@@ -61,7 +62,7 @@ abstract contract FallbackManager is SelfAuthorized {
     // solhint-disable-next-line payable-fallback,no-complex-fallback
     fallback() external {
         bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             // When compiled with the optimizer, the compiler relies on a certain assumptions on how the
@@ -96,5 +97,6 @@ abstract contract FallbackManager is SelfAuthorized {
             }
             return(returnDataPtr, returndatasize())
         }
+        /* solhint-enable no-inline-assembly */
     }
 }

contracts/base/GuardManager.sol

@@ -1,9 +1,10 @@
 // SPDX-License-Identifier: LGPL-3.0-only
+/* solhint-disable one-contract-per-file */
 pragma solidity >=0.7.0 <0.9.0;
 
-import "../common/Enum.sol";
-import "../common/SelfAuthorized.sol";
-import "../interfaces/IERC165.sol";
+import {Enum} from "../common/Enum.sol";
+import {SelfAuthorized} from "../common/SelfAuthorized.sol";
+import {IERC165} from "../interfaces/IERC165.sol";
 
 /// @title Guard Interface
 interface Guard is IERC165 {
@@ -89,11 +90,12 @@ abstract contract GuardManager is SelfAuthorized {
             require(Guard(guard).supportsInterface(type(Guard).interfaceId), "GS300");
         }
         bytes32 slot = GUARD_STORAGE_SLOT;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             sstore(slot, guard)
         }
+        /* solhint-enable no-inline-assembly */
         emit ChangedGuard(guard);
     }
 
@@ -106,10 +108,11 @@ abstract contract GuardManager is SelfAuthorized {
      */
     function getGuard() internal view returns (address guard) {
         bytes32 slot = GUARD_STORAGE_SLOT;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             guard := sload(slot)
         }
+        /* solhint-enable no-inline-assembly */
     }
 }

contracts/base/ModuleManager.sol

@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
-import "../common/Enum.sol";
-import "../common/SelfAuthorized.sol";
-import "./Executor.sol";
-import "./GuardManager.sol";
+import {Enum} from "../common/Enum.sol";
+import {SelfAuthorized} from "../common/SelfAuthorized.sol";
+import {Executor} from "./Executor.sol";
+import {GuardManager, Guard} from "./GuardManager.sol";
 
 /**
  * @title Module Manager - A contract managing Safe modules
@@ -119,7 +119,7 @@ abstract contract ModuleManager is SelfAuthorized, Executor, GuardManager {
         Enum.Operation operation
     ) public returns (bool success, bytes memory returnData) {
         success = execTransactionFromModule(to, value, data, operation);
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             // Load free memory location
@@ -134,6 +134,7 @@ abstract contract ModuleManager is SelfAuthorized, Executor, GuardManager {
             // Point the return data to the correct memory location
             returnData := ptr
         }
+        /* solhint-enable no-inline-assembly */
     }
 
     /**
@@ -180,11 +181,12 @@ abstract contract ModuleManager is SelfAuthorized, Executor, GuardManager {
             next = array[moduleCount - 1];
         }
         // Set correct size of returned array
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             mstore(array, moduleCount)
         }
+        /* solhint-enable no-inline-assembly */
     }
 
     /**
@@ -195,11 +197,12 @@ abstract contract ModuleManager is SelfAuthorized, Executor, GuardManager {
      */
     function isContract(address account) internal view returns (bool) {
         uint256 size;
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             size := extcodesize(account)
         }
+        /* solhint-enable no-inline-assembly */
         return size > 0;
     }
 }

contracts/base/OwnerManager.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
-import "../common/SelfAuthorized.sol";
+import {SelfAuthorized} from "../common/SelfAuthorized.sol";
 
 /**
  * @title OwnerManager - Manages Safe owners and a threshold to authorize transactions.

contracts/common/SecuredTokenTransfer.sol

@@ -19,7 +19,6 @@ abstract contract SecuredTokenTransfer {
         // 0xa9059cbb - keccack("transfer(address,uint256)")
         bytes memory data = abi.encodeWithSelector(0xa9059cbb, receiver, amount);
         // solhint-disable-next-line no-inline-assembly
-        /// @solidity memory-safe-assembly
         assembly {
             // We write the return value to scratch space.
             // See https://docs.soliditylang.org/en/v0.7.6/internals/layout_in_memory.html#layout-in-memory

contracts/common/SignatureDecoder.sol

@@ -19,13 +19,14 @@ abstract contract SignatureDecoder {
      * @return s Output value s of the signature.
      */
     function signatureSplit(bytes memory signatures, uint256 pos) internal pure returns (uint8 v, bytes32 r, bytes32 s) {
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             let signaturePos := mul(0x41, pos)
             r := mload(add(signatures, add(signaturePos, 0x20)))
             s := mload(add(signatures, add(signaturePos, 0x40)))
             v := byte(0, mload(add(signatures, add(signaturePos, 0x60))))
         }
+        /* solhint-enable no-inline-assembly */
     }
 }

contracts/common/StorageAccessible.sol

@@ -17,12 +17,13 @@ abstract contract StorageAccessible {
     function getStorageAt(uint256 offset, uint256 length) public view returns (bytes memory) {
         bytes memory result = new bytes(length * 32);
         for (uint256 index = 0; index < length; index++) {
-            // solhint-disable-next-line no-inline-assembly
+            /* solhint-disable no-inline-assembly */
             /// @solidity memory-safe-assembly
             assembly {
                 let word := sload(add(offset, index))
                 mstore(add(add(result, 0x20), mul(index, 0x20)), word)
             }
+            /* solhint-enable no-inline-assembly */
         }
         return result;
     }
@@ -39,7 +40,7 @@ abstract contract StorageAccessible {
      * @param calldataPayload Calldata that should be sent to the target contract (encoded method name and arguments).
      */
     function simulateAndRevert(address targetContract, bytes memory calldataPayload) external {
-        // solhint-disable-next-line no-inline-assembly
+        /* solhint-disable no-inline-assembly */
         /// @solidity memory-safe-assembly
         assembly {
             let success := delegatecall(gas(), targetContract, add(calldataPayload, 0x20), mload(calldataPayload), 0, 0)
@@ -50,5 +51,6 @@ abstract contract StorageAccessible {
             returndatacopy(add(ptr, 0x40), 0, returndatasize())
             revert(ptr, add(returndatasize(), 0x40))
         }
+        /* solhint-enable no-inline-assembly */
     }
 }

contracts/examples/guards/DebugTransactionGuard.sol

@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.7.0 <0.9.0;
 
-import "../../common/Enum.sol";
-import "../../base/GuardManager.sol";
-import "../../Safe.sol";
+import {Enum} from "../../common/Enum.sol";
+import {BaseGuard} from "../../base/GuardManager.sol";
+import {Safe} from "../../Safe.sol";
 
 /**
  * @title Debug Transaction Guard - Emits transaction events with extended information.