Pull copy/pasted nonce logic into virtual hook to allow flexibiltiy for explicit nonce-setting (#67)

Author: stevieraykatz

script/universal/MultisigBase.sol

@@ -19,21 +19,25 @@ abstract contract MultisigBase is Simulator {
         return keccak256(_encodeTransactionData(_safe, _data));
     }
 
-    function _encodeTransactionData(address _safe, bytes memory _data) internal view returns (bytes memory) {
-        // Ensure that the required contracts exist
-        require(address(multicall).code.length > 0, "multicall3 not deployed");
-        require(_safe.code.length > 0, "no code at safe address");
-
-        IGnosisSafe safe = IGnosisSafe(payable(_safe));
-        uint256 nonce = safe.nonce();
+    // Virtual method which can be overwritten
+    // Default logic here is vestigial for backwards compatibility
+    function _getNonce(IGnosisSafe safe) internal view virtual returns (uint256 nonce) {
+        nonce = safe.nonce();
         console.log("Safe current nonce:", nonce);
-
-        // workaround to check if the SAFE_NONCE env var is present
         try vm.envUint("SAFE_NONCE") {
             nonce = vm.envUint("SAFE_NONCE");
             console.log("Creating transaction with nonce:", nonce);
         }
         catch {}
+    }
+
+    function _encodeTransactionData(address _safe, bytes memory _data) internal view returns (bytes memory) {
+        // Ensure that the required contracts exist
+        require(address(multicall).code.length > 0, "multicall3 not deployed");
+        require(_safe.code.length > 0, "no code at safe address");
+
+        IGnosisSafe safe = IGnosisSafe(payable(_safe));
+        uint256 nonce = _getNonce(safe);
 
         return safe.encodeTransactionData({
             to: address(multicall),

script/universal/MultisigBuilder.sol

@@ -80,17 +80,7 @@ abstract contract MultisigBuilder is MultisigBase {
     function simulateSigned(bytes memory _signatures) public returns (bool) {
         address _safe = _ownerSafe();
         IGnosisSafe safe = IGnosisSafe(payable(_safe));
-
-        uint256 _nonce = safe.nonce();
-        console.log("Safe current nonce:", _nonce);
-
-        // workaround to check if the SAFE_NONCE env var is present
-        try vm.envUint("SAFE_NONCE") {
-            _nonce = vm.envUint("SAFE_NONCE");
-            console.log("Creating transaction with nonce:", _nonce);
-        }
-        catch {}
-
+        uint256 _nonce = _getNonce(safe);
         vm.store(_safe, bytes32(uint256(5)), bytes32(uint256(_nonce)));
         bool success = _executeTransaction(_safe, _buildCalls(), _signatures);
         if (success) _postCheck();
@@ -150,15 +140,7 @@ abstract contract MultisigBuilder is MultisigBase {
     // default logic is vestigial for backwards compatibility. 
     function _addOverrides(address _safe) internal virtual view returns (SimulationStateOverride memory) {
         IGnosisSafe safe = IGnosisSafe(payable(_safe));
-        uint256 _nonce = safe.nonce();
-        console.log("Safe current nonce:", _nonce);
-
-        // workaround to check if the SAFE_NONCE env var is present
-        try vm.envUint("SAFE_NONCE") {
-            _nonce = vm.envUint("SAFE_NONCE");
-            console.log("Creating transaction with nonce:", _nonce);
-        }
-        catch {}
+        uint256 _nonce = _getNonce(safe);
         return overrideSafeThresholdAndNonce(_safe, _nonce);
     }
 }