feat: add ERCTokenCallbacks Extension

packages/lsp17-contracts/contracts/ERCTokenCallbacks.sol

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.4;
+
+import {
+    ERC721Holder,
+    IERC721Receiver
+} from "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol";
+
+import {
+    ERC1155Holder,
+    ERC1155Receiver
+} from "@openzeppelin/contracts/token/ERC1155/utils/ERC1155Holder.sol";
+
+import {
+    IERC777Recipient
+} from "@openzeppelin/contracts/token/ERC777/IERC777Recipient.sol";
+
+import {
+    LSP17Extension
+} from "@lukso/lsp17contractextension-contracts/contracts/LSP17Extension.sol";
+
+/**
+ * @dev LSP17 Extension that can be attached to a LSP17Extendable contract
+ * to allow it to receive ERC721 tokens via `safeTransferFrom`.
+ */
+// solhint-disable-next-line no-empty-blocks
+contract ERCTokenCallbacks is
+    ERC721Holder,
+    ERC1155Holder,
+    IERC777Recipient,
+    LSP17Extension
+{
+    function tokensReceived(
+        address operator,
+        address from,
+        address to,
+        uint256 amount,
+        bytes calldata userData,
+        bytes calldata operatorData
+    ) external override {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    /**
+     * @notice Implements ERC165 interface support for ERC1155TokenReceiver, ERC721TokenReceiver and IERC165.
+     * @param interfaceId Id of the interface.
+     * @return if the interface is supported.
+     */
+    function supportsInterface(
+        bytes4 interfaceId
+    )
+        public
+        view
+        virtual
+        override(ERC1155Receiver, LSP17Extension)
+        returns (bool)
+    {
+        return
+            interfaceId == type(IERC721Receiver).interfaceId ||
+            super.supportsInterface(interfaceId);
+    }
+}

packages/lsp17-contracts/tests/ERCTokenCallbacks.test.ts

@@ -0,0 +1,31 @@
+import { expect } from 'chai';
+import { ethers } from 'hardhat';
+import { SignerWithAddress } from '@nomicfoundation/hardhat-ethers/signers';
+import { ERCTokenCallbacks, ERCTokenCallbacks__factory } from '../types';
+import { INTERFACE_ID_LSP17Extension } from '../constants.ts';
+
+describe('testing `ERCTokenCallbacks`', () => {
+  let context: {
+    tokenCallbacks: ERCTokenCallbacks;
+    owner: SignerWithAddress;
+  };
+
+  before(async () => {
+    const [owner] = await ethers.getSigners();
+    const tokenCallbacks = await new ERCTokenCallbacks__factory(owner).deploy();
+
+    context = {
+      tokenCallbacks,
+      owner,
+    };
+  });
+
+  describe('testing `supportsInterface`', () => {
+    it('should return true for supported interface IDs', async () => {
+      expect(await context.tokenCallbacks.supportsInterface(INTERFACE_ID_LSP17Extension)).to.be
+        .true; // LSP17Extension interface ID
+      expect(await context.tokenCallbacks.supportsInterface('0x01ffc9a7')).to.be.true; // ERC721Holder interface ID
+      expect(await context.tokenCallbacks.supportsInterface('0x4e2312e0')).to.be.true; // ERC1155Holder interface ID
+    });
+  });
+});