fix: add wrapper function for Delta.verify for the fuzzer

Author: heueristik

contracts/test/proofs/DeltaProof.t.sol

@@ -25,6 +25,11 @@ contract DeltaProofTest is Test {
         bool consumed;
     }
 
+    /// @dev This function exposes `Delta.verify` for the fuzzer.
+    function verifyDelta(bytes memory proof, uint256[2] memory instance, bytes32 verifyingKey) public pure {
+        Delta.verify({proof: proof, instance: instance, verifyingKey: verifyingKey});
+    }
+
     function testFuzz_verify_delta_succeeds(
         uint256 kind,
         uint256 valueCommitmentRandomness,
@@ -54,7 +59,7 @@ contract DeltaProofTest is Test {
         bytes memory proof = DeltaGen.generateProof(vm, deltaProofInputs);
 
         // Verify that the generated delta proof is valid
-        Delta.verify({proof: proof, instance: instance, verifyingKey: deltaProofInputs.verifyingKey});
+        verifyDelta({proof: proof, instance: instance, verifyingKey: deltaProofInputs.verifyingKey});
     }
 
     /// @notice Test that Delta.add correctly adds deltas
@@ -140,7 +145,7 @@ contract DeltaProofTest is Test {
         uint256[2] memory instance = DeltaGen.generateInstance(vm, deltaInstanceInputs);
         bytes memory proof = DeltaGen.generateProof(vm, deltaProofInputs);
         vm.expectPartialRevert(Delta.DeltaMismatch.selector);
-        Delta.verify({proof: proof, instance: instance, verifyingKey: deltaProofInputs.verifyingKey});
+        verifyDelta({proof: proof, instance: instance, verifyingKey: deltaProofInputs.verifyingKey});
     }
 
     /// @notice Test that Delta.verify rejects a delta proof that does not correspond to instance
@@ -175,7 +180,7 @@ contract DeltaProofTest is Test {
         }
 
         vm.expectPartialRevert(Delta.DeltaMismatch.selector);
-        Delta.verify({proof: proofRcv1, instance: instanceRcv2, verifyingKey: verifyingKey});
+        verifyDelta({proof: proofRcv1, instance: instanceRcv2, verifyingKey: verifyingKey});
     }
 
     /// @notice Test that Delta.verify rejects a delta proof that does not correspond to the verifying key
@@ -209,7 +214,7 @@ contract DeltaProofTest is Test {
         }
 
         vm.expectPartialRevert(Delta.DeltaMismatch.selector);
-        Delta.verify({proof: proofForVk1, instance: instance, verifyingKey: verifyingKey2});
+        verifyDelta({proof: proofForVk1, instance: instance, verifyingKey: verifyingKey2});
     }
 
     /// @notice Check that a balanced transaction does pass verification
@@ -261,7 +266,7 @@ contract DeltaProofTest is Test {
 
         bytes memory proof = DeltaGen.generateProof(vm, sumDeltaInputs);
         // Verify that the balanced transaction proof succeeds
-        Delta.verify({proof: proof, instance: deltaAcc, verifyingKey: verifyingKey});
+        verifyDelta({proof: proof, instance: deltaAcc, verifyingKey: verifyingKey});
     }
 
     /// @notice Check that an imbalanced transaction fails verification
@@ -302,13 +307,13 @@ contract DeltaProofTest is Test {
         bytes memory proof = DeltaGen.generateProof(vm, sumDeltaInputs);
         // Verify that the imbalanced transaction proof fails
         vm.expectPartialRevert(Delta.DeltaMismatch.selector);
-        Delta.verify({proof: proof, instance: deltaAcc, verifyingKey: verifyingKey});
+        verifyDelta({proof: proof, instance: deltaAcc, verifyingKey: verifyingKey});
     }
 
     function test_verify_example_delta_proof() public pure {
         Transaction memory txn = TransactionExample.transaction();
 
-        Delta.verify({
+        verifyDelta({
             proof: txn.deltaProof,
             instance: [
                 uint256(txn.actions[0].complianceVerifierInputs[0].instance.unitDeltaX),