added echidna fuzz tests

README.md

@@ -5,6 +5,14 @@ Create a digital passport for your physical items.
 
 ![100 Percent Coverage](./images/100coverage.png)
 
+## Static Analysis!
+
+[Slither Report](./contract/Slither-Report.md)
+
+## Fuzzing!
+
+![Echidna Fuzzing Results](./images/echidna.png)
+
 ## Description
 
 A dApp that allows users to create a digital passport for physical items and make the information associated with these items easily accessible.

contract/echidna/PropertyTest.sol

@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.18;
+
+import "../src/ItemBlocks.sol";
+
+/**
+ * @title 
+ * @author 
+ * @notice 
+ * 
+ * @dev There are some specific addresses in Echidna:
+        0x30000 calls the constructor.
+        0x10000, 0x20000, and 0x30000 randomly call other functions.
+ */
+contract ItemBlocksPropertyTest is ItemBlocks {
+    uint256 testTokenId = 0;
+
+    constructor() ItemBlocks(address(0x30000)) {
+        testTokenId = createPassport(7, "TestItemName", "TestItemDesc", "TestItemFamily", "TestItemUrl","TestItemImg");
+    }
+
+    // owner should never be zero address
+    function echidna_owner_not_zero() public view returns (bool) {
+        return ownerOf(testTokenId) != address(0);
+    }
+
+    // item creator should always be the first entry in allItem Owners
+    function echidna_set_creator() public view returns (bool){
+        return allItemOwners[7][0] == address(0x30000);
+    }
+
+    // it should be possible to create more items
+    function echidna_create_more() public view returns (bool) {
+        return createdItems[address(0x30000)].length >= 1;
+    }
+
+    // if there is a owner in the allItemsOwners array there should be a passport too
+    function echidna_need_to_create_history_and_passport() public view returns (bool) {
+        if (allItemOwners[7].length > 0) {
+            return bytes(itemPassports[7].name).length > 0;
+        } else {
+            return true;
+        }
+    }
+
+    // current owner should be the last entry in allItemOwners
+    function echidna_owner_is_last_entry_allItemOwners() public view returns (bool) {
+        if (allItemOwners[1].length > 0) {
+            address[] memory test = allItemOwners[1];
+            return test[test.length - 1] == ownerOf(1);
+        } else {
+            return true;
+        }
+    }
+
+}

contract/src/ItemBlocks.sol

@@ -33,13 +33,13 @@ contract ItemBlocks is ERC721, Ownable {
         _safeMint(to, tokenId);
     }
 
-    function createPassport(uint tokenId, string calldata name, string calldata desc, string calldata family, string calldata url, string calldata img) public returns(uint256) {
+    function createPassport(uint tokenId, string memory name, string memory desc, string memory family, string memory url, string memory img) public returns(uint256) {
         _safeMint(msg.sender, tokenId);
         setCreator(msg.sender, tokenId);
         return updatePassport(tokenId, name, desc, family, url, img);
     }
 
-    function updatePassport(uint tokenId, string calldata name, string calldata desc, string calldata family, string calldata url, string calldata img) public returns(uint256) {        
+    function updatePassport(uint tokenId, string memory name, string memory desc, string memory family, string memory url, string memory img) public returns(uint256) {        
         require( isEligible(tokenId, msg.sender), "Must be the owner of the item or the creator of it" );
 
         itemPassports[tokenId] = Passport ({