feat: implement IERC165

package.json

@@ -40,6 +40,7 @@
   "devDependencies": {
     "@commitlint/cli": "19.3.0",
     "@commitlint/config-conventional": "19.2.2",
+    "@openzeppelin/contracts": "5.4.0",
     "forge-std": "github:foundry-rs/forge-std#1.9.2",
     "halmos-cheatcodes": "github:a16z/halmos-cheatcodes#c0d8655",
     "husky": ">=9",

remappings.txt

@@ -1,5 +1,6 @@
 forge-std/=node_modules/forge-std/src
 halmos-cheatcodes=node_modules/halmos-cheatcodes
+openzeppelin-contracts=node_modules/@openzeppelin/contracts
 
 contracts/=src/contracts
 interfaces/=src/interfaces

src/contracts/L2Resolver.sol

@@ -1,7 +1,9 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.30;
 
+import {IERC165} from 'openzeppelin-contracts/interfaces/IERC165.sol';
 import {IENS} from 'src/interfaces/IENS.sol';
+import {IExtendedResolver} from 'src/interfaces/IExtendedResolver.sol';
 import {IL2Resolver} from 'src/interfaces/IL2Resolver.sol';
 import {INameWrapper} from 'src/interfaces/INameWrapper.sol';
 
@@ -12,7 +14,7 @@ import {INameWrapper} from 'src/interfaces/INameWrapper.sol';
  * formatted chain identifiers and allows reverse lookup by mapping them back to their primary ENS names.
  * EIP-7930 is an example of supported chain identifier.
  */
-contract L2Resolver is IL2Resolver {
+contract L2Resolver is IL2Resolver, IERC165 {
   /// @inheritdoc IL2Resolver
   bytes32 public constant REVERSE_LOOKUP_NODE = bytes32(keccak256('reverse.chain.id.eip7930'));
 
@@ -81,6 +83,11 @@ contract L2Resolver is IL2Resolver {
     _chainId = this.getRecord(_node, CHAIN_IDENTIFIER_EIP7930_KEY);
   }
 
+  /// @inheritdoc IERC165
+  function supportsInterface(bytes4 _interfaceId) public view virtual override returns (bool _isSupported) {
+    _isSupported = _interfaceId == type(IERC165).interfaceId || _interfaceId == type(IExtendedResolver).interfaceId;
+  }
+
   /**
    * @notice Returns the owner of a node.
    * @dev If the node is the NameWrapper, then the domain is wrapped and it gets the owner from the NameWrapper.

src/interfaces/IExtendedResolver.sol

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.30;
+
+interface IExtendedResolver {
+  /**
+   * @notice Provides a mechanism to support wildcard resolution of ENS names
+   * @param _name The name to resolve
+   * @param _data The data to resolve
+   * @return _result The result of the resolution
+   */
+  function resolve(bytes memory _name, bytes memory _data) external view returns (bytes memory _result);
+}

test/unit/L2Resolver.t.sol

@@ -2,9 +2,11 @@
 pragma solidity 0.8.30;
 
 import {Test} from 'forge-std/Test.sol';
+import {IERC165} from 'openzeppelin-contracts/interfaces/IERC165.sol';
 import {L2Resolver} from 'src/contracts/L2Resolver.sol';
 
 import {IENS} from 'src/interfaces/IENS.sol';
+import {IExtendedResolver} from 'src/interfaces/IExtendedResolver.sol';
 import {IL2Resolver} from 'src/interfaces/IL2Resolver.sol';
 import {INameWrapper} from 'src/interfaces/INameWrapper.sol';
 
@@ -343,6 +345,24 @@ contract UnitL2Resolver is Test {
     assertEq(_l2Resolver.chainId(_nodeNameHash), '');
   }
 
+  function test_SupportsInterfaceWhenCheckingERC165InterfaceId() external view {
+    // it returns true
+    assertTrue(_l2Resolver.supportsInterface(type(IERC165).interfaceId));
+  }
+
+  function test_SupportsInterfaceWhenCheckingExtendedResolverInterfaceId() external view {
+    // it returns true
+    assertTrue(_l2Resolver.supportsInterface(type(IExtendedResolver).interfaceId));
+  }
+
+  function test_SupportsInterfaceWhenCheckingAnUnsupportedInterfaceId(bytes4 _interfaceId) external view {
+    vm.assume(_interfaceId != type(IERC165).interfaceId);
+    vm.assume(_interfaceId != type(IExtendedResolver).interfaceId);
+
+    // it returns false
+    assertFalse(_l2Resolver.supportsInterface(_interfaceId));
+  }
+
   /**
    * @notice Sets up a mock and expects a call to it
    *

test/unit/L2Resolver.tree

@@ -50,3 +50,11 @@ UnitL2Resolver::chainId
 │   └── it returns the stored EIP-7930 bytes
 └── when the chain identifier is not set
     └── it returns empty bytes
+
+UnitL2Resolver::supportsInterface
+├── when checking ERC165 interface id
+│   └── it returns true
+├── when checking ExtendedResolver interface id
+│   └── it returns true
+└── when checking an unsupported interface id
+    └── it returns false

yarn.lock

@@ -202,6 +202,11 @@
     "@nodelib/fs.scandir" "2.1.5"
     fastq "^1.6.0"
 
+"@openzeppelin/contracts@5.4.0":
+  version "5.4.0"
+  resolved "https://registry.yarnpkg.com/@openzeppelin/contracts/-/contracts-5.4.0.tgz#177594bdb2d86c71f5d1052fe40cb4edb95fb20f"
+  integrity sha512-eCYgWnLg6WO+X52I16TZt8uEjbtdkgLC0SUX/xnAksjjrQI4Xfn4iBRoI5j55dmlOhDv1Y7BoR3cU7e3WWhC6A==
+
 "@solidity-parser/parser@^0.19.0":
   version "0.19.0"
   resolved "https://registry.yarnpkg.com/@solidity-parser/parser/-/parser-0.19.0.tgz#37a8983b2725af9b14ff8c4a475fa0e98d773c3f"