chore: refactor fuzzing campaign so it more closely resembles what we…

… use in production

test/invariants/PROPERTIES.md

@@ -1,4 +1,4 @@
-| Properties                                        | Type       |
-|---------------------------------------------------|------------|
-| Greeting should never be empty | Valid state |
-| Only the owner can set the greeting | State transition |
+| id  | Properties                                          | Type             |
+| --- | --------------------------------------------------- | ------------     |
+| 1   | Greeting should never be empty                      | Valid state      |
+| 2   | Only the owner can set the greeting                 | State transition |

test/invariants/fuzz/Greeter.t.sol

@@ -2,36 +2,39 @@
 pragma solidity 0.8.23;
 
 import {Greeter, IERC20} from 'contracts/Greeter.sol';
+import {CommonBase} from 'forge-std/Base.sol';
 
-interface IHevm {
-  function prank(address) external;
-}
-
-contract InvariantGreeter {
-  IHevm internal _hevm = IHevm(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);
-
+contract InvariantGreeter is CommonBase {
   Greeter internal _targetContract;
 
   constructor() {
     _targetContract = new Greeter('a', IERC20(address(1)));
   }
 
-  function checkGreeterNeverEmpty(string memory _newGreeting) public {
-    // Execution
-    (bool _success,) = address(_targetContract).call(abi.encodeCall(Greeter.setGreeting, _newGreeting));
-
-    // Check output condition
-    assert((_success && keccak256(bytes(_targetContract.greeting())) != keccak256(bytes(''))) || !_success);
+  /// @custom:property-id 2
+  /// @custom:property Only the owner can set the greeting
+  function handler_unguided_setGreeting(address _caller, string memory _newGreeting) external {
+    vm.prank(_caller);
+    try _targetContract.setGreeting(_newGreeting) {
+      assert(keccak256(bytes(_targetContract.greeting())) == keccak256(bytes(_newGreeting)));
+      assert(_caller == _targetContract.OWNER());
+    } catch {
+      assert(_caller != _targetContract.OWNER() || keccak256(bytes(_newGreeting)) == keccak256(''));
+    }
   }
 
-  function checkOnlyOwnerSetsGreeting(address _caller) public {
-    // Input conditions
-    _hevm.prank(_caller);
-
-    // Execution
-    (bool _success,) = address(this).call(abi.encodeCall(Greeter.setGreeting, 'hello'));
+  function handler_guided_setGreeting(string memory _newGreeting) external {
+    // no need to prank since this contract deployed the greeter and is therefore its owner
+    try _targetContract.setGreeting(_newGreeting) {
+      assert(keccak256(bytes(_targetContract.greeting())) == keccak256(bytes(_newGreeting)));
+    } catch {
+      assert(keccak256(bytes(_newGreeting)) == keccak256(''));
+    }
+  }
 
-    // Check output condition
-    assert((_success && msg.sender == _targetContract.OWNER()) || (!_success && msg.sender != _targetContract.OWNER()));
+  /// @custom:property-id 1
+  /// @custom:property Greeting should never be empty
+  function property_greetingIsNeverEmpty() external view {
+    assert(keccak256(bytes(_targetContract.greeting())) != keccak256(''));
   }
 }