Merge branch 'audit-asahi' into audit

src/TokenDivider.sol

@@ -222,23 +222,24 @@ contract TokenDivider is IERC721Receiver, Ownable {
         if (amount == 0) {
             revert TokenDivider__AmountCantBeZero();
         }
-
-	// @audit: no checks for 0 price?
+	// @audit: no check for 0 price?
 
         ERC20Info memory tokenInfo = nftToErc20Info[nftPegged];
         if (balances[msg.sender][tokenInfo.erc20Address] < amount) {
             revert TokenDivider__InsuficientBalance();
         }
 
-        balances[msg.sender][tokenInfo.erc20Address] -= amount;
+        balances[msg.sender][tokenInfo.erc20Address] -= amount; // token amount reduced from its holder on sell order even tho no one buy it
 
+	// push sell order to array of sender
         s_userToSellOrders[msg.sender].push(
             SellOrder({seller: msg.sender, erc20Address: tokenInfo.erc20Address, price: price, amount: amount})
         );
 
         emit OrderPublished(amount, msg.sender, nftPegged);
 
-	// @audit: what if I cancel
+	// send erc20 token from owner to this contract
+	// @audit: what if the owner of ERC20 rejected this transaction?
         IERC20(tokenInfo.erc20Address).transferFrom(msg.sender, address(this), amount);
     }
 
@@ -257,19 +258,24 @@ contract TokenDivider is IERC721Receiver, Ownable {
 
         SellOrder memory order = s_userToSellOrders[seller][orderIndex];
 
+	// msg.value can be greater than order price?
         if (msg.value < order.price) {
             revert TokenDivider__IncorrectEtherAmount();
         }
 
+	// if price 100, then fee is 1
         uint256 fee = order.price / 100;
+	// if price 100, then seller fee is 0.5
         uint256 sellerFee = fee / 2;
 
         if (msg.value < order.price + sellerFee) {
             revert TokenDivider__InsuficientEtherForFees();
         }
 
+	// record erc20 amount on storage variable onchain
         balances[msg.sender][order.erc20Address] += order.amount;
 
+	// override the current orderIndex with tail, then pop the tail out of array
         s_userToSellOrders[seller][orderIndex] = s_userToSellOrders[seller][s_userToSellOrders[seller].length - 1];
         s_userToSellOrders[seller].pop();
 
@@ -277,18 +283,23 @@ contract TokenDivider is IERC721Receiver, Ownable {
 
         // Transfer The Ether
 
+	// send ether to seller, reduced with seller fee
         (bool success,) = payable(order.seller).call{value: (order.price - sellerFee)}("");
 
         if (!success) {
             revert TokenDivider__TransferFailed();
         }
 
+	// send "fee" to "owner"? 
+	// @audit: if buyer needs to pay price + seller fee. then seller is given price - seller fee. does fee is guarranted to be paid by buyer?
+	// @audit: who owner?
         (bool taxSuccess,) = payable(owner()).call{value: fee}("");
 
         if (!taxSuccess) {
             revert TokenDivider__TransferFailed();
         }
 
+	// send erc20 token to buyer address
         IERC20(order.erc20Address).transfer(msg.sender, order.amount);
     }
 

test/unit/TokenDividerTest.audit.divideNft.t.sol

@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.18;
+
+
+import {Test, console} from 'forge-std/Test.sol';
+import {DeployTokenDivider} from 'script/DeployTokenDivider.s.sol';
+import {TokenDivider} from 'src/TokenDivider.sol';
+import {ERC721Mock} from '../mocks/ERC721Mock.sol';
+import {ERC20Mock} from '@openzeppelin/contracts/mocks/token/ERC20Mock.sol';
+import {Ownable} from '@openzeppelin/contracts/access/Ownable.sol';
+
+
+contract TokenDiverTest is Test {
+    DeployTokenDivider deployer;
+    TokenDivider tokenDivider;
+    ERC721Mock erc721Mock;
+
+    address public USER = makeAddr("user");
+    address public USER2 = makeAddr("user2");
+    uint256 constant public STARTING_USER_BALANCE = 10e18;
+    uint256 constant public AMOUNT = 2e18;
+    uint256 constant public TOKEN_ID = 0;
+
+    function setUp() public {
+        deployer = new DeployTokenDivider();
+        tokenDivider = deployer.run();
+        
+        erc721Mock = new ERC721Mock();
+        
+        erc721Mock.mint(USER); // @auditor: user has the NFT
+        vm.deal(USER2, STARTING_USER_BALANCE); // @auditor: user2 got 10 ether
+    }
+
+    function test_assertSetUp() public {
+    	// then what?
+
+	// USER has no ERC721 NFT of TOKEN_ID
+	assertTrue(address(erc721Mock.ownerOf(TOKEN_ID)) == address(USER2));
+	// USER has no balance
+	// USER2 has STARTING_USER_BALANCE
+    }
+
+    /*
+    function testDivideNft() public {
+        
+        vm.startPrank(USER);
+        erc721Mock.approve(address(tokenDivider), TOKEN_ID);
+
+        tokenDivider.divideNft(address(erc721Mock), TOKEN_ID, AMOUNT);
+        vm.stopPrank();
+        ERC20Mock erc20Mock = ERC20Mock(tokenDivider.getErc20InfoFromNft(address(erc721Mock)).erc20Address);
+
+        console.log("ERC20 Token name is: ", erc20Mock.name());
+        console.log("ERC20 Token symbol is: ", erc20Mock.symbol());
+        assertEq(tokenDivider.getErc20TotalMintedAmount(address(erc20Mock)), AMOUNT);
+        assertEq(erc721Mock.ownerOf(TOKEN_ID), address(tokenDivider));
+        assertEq(tokenDivider.getBalanceOf(USER,  address(erc20Mock)), AMOUNT);
+
+    }
+
+
+    modifier nftDivided() {
+        vm.startPrank(USER);
+        erc721Mock.approve(address(tokenDivider), TOKEN_ID);
+        tokenDivider.divideNft(address(erc721Mock), TOKEN_ID, AMOUNT);
+        vm.stopPrank();
+
+        _;
+
+    }
+
+    function testDivideNftFailsIsSenderIsNotNftOwner() public {
+        vm.prank(USER);
+        erc721Mock.approve(address(tokenDivider), TOKEN_ID);
+
+        vm.startPrank(USER2);
+        vm.expectRevert(TokenDivider.TokenDivider__NotFromNftOwner.selector);
+        tokenDivider.divideNft(address(erc721Mock), TOKEN_ID, AMOUNT);
+        vm.stopPrank();
+    }
+     */
+
+}