fuzz test getPreviousOwnerInLinkedList

test/unit/handlers/SafeRecoveryCommandHandler/fuzz/getPreviousOwnerInLinkedList.t.sol

@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.25;
+
+import { SafeNativeIntegrationBase } from
+    "../../../../integration/SafeRecovery/SafeNativeIntegrationBase.t.sol";
+import { SafeRecoveryCommandHandlerHarness } from "../../../SafeRecoveryCommandHandlerHarness.sol";
+
+interface ISafe {
+    function addOwnerWithThreshold(address owner, uint256 _threshold) external;
+    function getOwners() external view returns (address[] memory);
+    function isOwner(address owner) external view returns (bool);
+}
+
+contract SafeRecoveryCommandHandler_getPreviousOwnerInLinkedList_Fuzz_Test is
+    SafeNativeIntegrationBase
+{
+    address internal constant SENTINEL_OWNERS = address(0x1);
+
+    SafeRecoveryCommandHandlerHarness public safeRecoveryCommandHandler;
+
+    function setUp() public override {
+        super.setUp();
+        safeRecoveryCommandHandler = new SafeRecoveryCommandHandlerHarness();
+    }
+
+    function testFuzz_GetPreviousOwnerInLinkedList_Succeeds(address[] memory owners) public {
+        skipIfNotSafeAccountType();
+
+        vm.startPrank(accountAddress1);
+        for (uint256 i = 0; i < owners.length; i++) {
+            if (ISafe(accountAddress1).isOwner(owners[i])) {
+                break;
+            }
+            vm.assume(owners[i] != address(0));
+            vm.assume(owners[i] != address(1));
+            vm.assume(owners[i] != accountAddress1);
+            ISafe(accountAddress1).addOwnerWithThreshold(owners[i], 1);
+        }
+        vm.stopPrank();
+
+        address[] memory ownersArr = ISafe(accountAddress1).getOwners();
+
+        address expectedPreviousOwner;
+        for (uint256 i = 1; i < ownersArr.length; i++) {
+            address previousOwner = safeRecoveryCommandHandler.exposed_getPreviousOwnerInLinkedList(
+                accountAddress1, ownersArr[i]
+            );
+            if (i == 0) {
+                assertEq(previousOwner, SENTINEL_OWNERS);
+            }
+
+            uint256 prevOwnerIndex = i - 1;
+            expectedPreviousOwner = ownersArr[prevOwnerIndex];
+
+            assertEq(expectedPreviousOwner, previousOwner);
+        }
+    }
+}