Misc fixes

contracts/ERC721Baseline.sol

@@ -14,7 +14,6 @@ import {Utils} from "./Utils.sol";
  * @custom:version v0.1.0-alpha.3
  * @notice A baseline ERC721 contract implementation that exposes internal methods to a proxy instance.
  */
-
 contract ERC721Baseline is ERC721, IERC2981, IERC721Baseline {
 
   /**
@@ -39,6 +38,9 @@ contract ERC721Baseline is ERC721, IERC2981, IERC721Baseline {
    * Supported Interfaces
    ************************************************/
 
+  /**
+   * @inheritdoc IERC165
+   */
   function supportsInterface(bytes4 interfaceId) public view override(IERC165, ERC721) returns (bool) {
     return (
       interfaceId == /* NFT Royalty Standard */ type(IERC2981).interfaceId ||
@@ -105,8 +107,6 @@ contract ERC721Baseline is ERC721, IERC2981, IERC721Baseline {
     return _symbol;
   }
 
-  event MetadataUpdate(uint256 tokenId);
-
   /**
    * Metadata > Token URI
    */
@@ -199,7 +199,7 @@ contract ERC721Baseline is ERC721, IERC2981, IERC721Baseline {
   function royaltyInfo(
     uint256,
     uint256
-  ) external pure returns (address receiver, uint256 royaltyAmount) {
+  ) external pure returns (address, uint256) {
     return (address(0), 0);
   }
 
@@ -488,14 +488,14 @@ contract ERC721Baseline is ERC721, IERC2981, IERC721Baseline {
   /**
    * @inheritdoc IERC721Baseline
    */
-  function recover(bytes32 hash, bytes memory signature) external view returns (address result) {
+  function recover(bytes32 hash, bytes memory signature) external view returns (address) {
     return Utils.recover(Utils.toEthSignedMessageHash(hash), signature);
   }
 
   /**
    * @inheritdoc IERC721Baseline
    */
-  function recoverCalldata(bytes32 hash, bytes calldata signature) external view returns (address result) {
+  function recoverCalldata(bytes32 hash, bytes calldata signature) external view returns (address) {
     return Utils.recoverCalldata(Utils.toEthSignedMessageHash(hash), signature);
   }
 

contracts/IERC721Baseline.sol

@@ -9,7 +9,6 @@ import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
  * @custom:version v0.1.0-alpha.3
  * @notice A baseline ERC721 contract implementation that exposes internal methods to a proxy instance.
  */
-
 interface IERC721Baseline is IERC721 {
 
   /**
@@ -44,6 +43,29 @@ interface IERC721Baseline is IERC721 {
    * Metadata
    ************************************************/
 
+  /**
+   * Metadata > ERC-4906 events
+   */
+
+  /**
+   * @dev This event emits when the metadata of a token is changed.
+   * So that the third-party platforms such as NFT market could
+   * timely update the images and related attributes of the NFT.
+   *
+   * @param _tokenId the token ID being updated
+   */
+  event MetadataUpdate(uint256 _tokenId);
+
+  /**
+   * @dev This event emits when the metadata of a range of tokens is changed.
+   * So that the third-party platforms such as NFT market could
+   * timely update the images and related attributes of the NFTs.
+   *
+   * @param _fromTokenId the starting token ID
+   * @param _toTokenId the ending token ID
+   */
+  event BatchMetadataUpdate(uint256 _fromTokenId, uint256 _toTokenId);
+
   /**
    * @notice The total minted supply.
    * @dev The supply is decreased when a token is burned.
@@ -72,6 +94,8 @@ interface IERC721Baseline is IERC721 {
   /**
    * @notice Sets the token URI for a token ID.
    * @dev Emits EIP-4906's `MetadataUpdate` event with the `tokenId`.
+   * This method is internal and only the proxy contract can call it.
+   *
    *
    * @param tokenId token ID
    * @param tokenURI URI pointing to the metadata
@@ -80,6 +104,7 @@ interface IERC721Baseline is IERC721 {
 
   /**
    * @notice Returns the shared URI for the tokens.
+   * @dev This method is internal and only the proxy contract can call it.
    */
   function __sharedURI() external view returns (string memory);
 
@@ -89,6 +114,8 @@ interface IERC721Baseline is IERC721 {
    * because ERC721Baseline allows to mint any token ID, starting at any index.
    * The proxy should emit `BatchMetadataUpdate`.
    *
+   * This method is internal and only the proxy contract can call it.
+   *
    * @param sharedURI shared URI for the tokens
    */
   function __setSharedURI(string calldata sharedURI) external;
@@ -105,6 +132,8 @@ interface IERC721Baseline is IERC721 {
    * because ERC721Baseline allows to mint any token ID, starting at any index.
    * The proxy should emit `BatchMetadataUpdate`.
    *
+   * This method is internal and only the proxy contract can call it.
+   *
    * @param baseURI shared base URI for the tokens
    */
   function __setBaseURI(string calldata baseURI) external;
@@ -173,15 +202,13 @@ interface IERC721Baseline is IERC721 {
 
   /**
    * @dev See {ERC721-_checkOnERC721Received}.
-   * This method is internal and only the proxy contract can call it.
    *
-   * @dev NOTE that this method accepts an additional first parameter that is the original transaction's `msg.sender`.
+   * NOTE: this method accepts an additional first parameter that is the original transaction's `msg.sender`.
    */
   function __checkOnERC721Received(address sender, address from, address to, uint256 tokenId, bytes memory data) external;
 
   /**
    * @dev See {ERC721-_isAuthorized}.
-   * This method is internal and only the proxy contract can call it.
    */
   function __isAuthorized(address owner, address spender, uint256 tokenId) external view returns (bool);
 
@@ -292,6 +319,11 @@ interface IERC721Baseline is IERC721 {
    * Utils
    ************************************************/
 
+  /**
+   * @dev Indicates an invalid signature.
+   */
+  error InvalidSignature();
+
   /**
    * @notice Recovers the signer's address from a message digest `hash`, and the `signature`.
    *

contracts/Utils.sol

@@ -7,14 +7,11 @@ pragma solidity 0.8.21;
  * @custom:version v0.1.0-alpha.3
  * @notice Utilities used in ERC721Baseline.
  */
-
 library Utils {
   /************************************************
    * ECDSA Utils
    ************************************************/
 
-  error InvalidSignature();
-
   /**
    * recover
    *

contracts/mocks/ERC721ConstructorAttackerMock.sol

@@ -6,7 +6,6 @@ import {IERC721Baseline} from "../IERC721Baseline.sol";
 
 /// @title {title}
 /// @author {name}
-
 contract ERC721ConstructorAttackerMock {
   constructor(address ERC721BaselineImplementation) {
     IERC721Baseline(ERC721BaselineImplementation).initialize("hack", "HACK");

contracts/mocks/ERC721ProxyMock.sol

@@ -9,7 +9,6 @@ import {IERC721Baseline} from "../IERC721Baseline.sol";
 
 /// @title {title}
 /// @author {name}
-
 contract ERC721ProxyMock is Proxy {
 
   IERC721Baseline baseline = IERC721Baseline(address(this));
@@ -78,8 +77,6 @@ contract ERC721ProxyMock is Proxy {
 
     require(_beforeTokenTransferHookEnabled, 'not enabled');
 
-    // @todo Try to alter state and make sure it is not reflected in the implementation.
-
     if (sender == to) {
       revert('Call to self');
     }

package.json

@@ -28,7 +28,7 @@
     "truffle": "^5.11.2"
   },
   "dependencies": {
-    "@openzeppelin/contracts": "5.0.0"
+    "@openzeppelin/contracts": "5.0.1"
   },
   "prettier": {
     "plugins": [

test/ERC721Baseline.js

@@ -374,6 +374,90 @@ contract(
         });
       });
 
+      describe("Metadata", () => {
+        it("sets name and symbols", async () => {
+          assert.equal("Test", await proxyDelegate.name());
+          assert.equal("TEST", await proxyDelegate.symbol());
+        });
+
+        it("updates totalSupply correctly", async () => {
+          await proxy.onlyProxy_mint(user, 3);
+          assert.equal(1, await proxyDelegate.totalSupply());
+          await proxy.onlyProxy_burn(3, { from: user });
+          assert.equal(0, await proxyDelegate.totalSupply());
+        });
+
+        describe("token URI", () => {
+          const tokenId = 3;
+
+          beforeEach(async () => {
+            await proxy.onlyProxy_mint(user, tokenId);
+          });
+
+          it("throws if the token does not exist", async () => {
+            await expectRevert(
+              proxyDelegate.tokenURI(100),
+              "ERC721NonexistentToken(uint256)",
+            );
+          });
+
+          it("returns empty string when nothing is set", async () => {
+            assert.equal("", await proxyDelegate.tokenURI(tokenId));
+          });
+
+          it("returns token-specific URI when set", async () => {
+            const anotherTokenId = tokenId + 1;
+            const uri = "ipfs://test";
+
+            await proxy.onlyProxy_mint(user, anotherTokenId, uri);
+
+            assert.equal(uri, await proxyDelegate.tokenURI(anotherTokenId));
+            assert.equal(uri, await proxyDelegate.__tokenURI(anotherTokenId));
+
+            assert.equal("", await proxyDelegate.tokenURI(tokenId));
+          });
+
+          it("can update token-specific URI and emits MetadataUpdate", async () => {
+            const uri = "ipfs://updated";
+            const receipt = await proxy.onlyProxy_setTokenURI(tokenId, uri);
+
+            await expectEvent.inTransaction(
+              receipt.tx,
+              proxyDelegate,
+              "MetadataUpdate",
+              {
+                _tokenId: String(tokenId),
+              },
+            );
+
+            assert.equal(uri, await proxyDelegate.tokenURI(tokenId));
+            assert.equal(uri, await proxyDelegate.__tokenURI(tokenId));
+          });
+
+          it("can define shared URI", async () => {
+            const uri = "ipfs://shared";
+
+            const anotherTokenId = tokenId + 1;
+            await proxy.onlyProxy_mint(user, anotherTokenId);
+
+            await proxy.onlyProxy_setSharedURI(uri);
+
+            assert.equal(uri, await proxyDelegate.tokenURI(anotherTokenId));
+            assert.equal(
+              await proxyDelegate.tokenURI(tokenId),
+              await proxyDelegate.tokenURI(anotherTokenId),
+            );
+          });
+
+          it("can set base URI", async () => {
+            const uri = "ipfs://base/";
+            await proxy.onlyProxy_setBaseURI(uri);
+
+            assert.equal(uri + tokenId, await proxyDelegate.tokenURI(tokenId));
+          });
+        });
+      });
+
       describe("Utils", () => {
         describe("recover", () => {
           const signer = web3.eth.accounts.create();