Add erc20 transfer with different implementation

.tool-versions

@@ -1,2 +1,3 @@
 nodejs 20.12.2
 solidity 0.8.24
+yarn 1.22.19

contracts/utils/MultiSendErc20.sol

@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+
+/**
+ * @title MultiSendErc20
+ * @notice A utility contract for sending ERC20 tokens to multiple recipients in a single transaction
+ */
+contract MultiSendErc20 {
+    using SafeERC20 for IERC20;
+
+    /// @notice Maximum number of recipients allowed in a single batch
+    uint256 public constant ARRAY_LIMIT = 200;
+
+    /// @dev Custom errors for gas-efficient reverts
+    error MismatchedArrays();
+    error ArrayLengthExceedsLimit();
+
+    /// @notice Emitted when a batch of ERC20 transfers is completed
+    /// @param total The total amount of tokens sent
+    event Multisended(uint256 total);
+
+    /**
+     * @notice Send ERC20 tokens to multiple recipients in a single transaction
+     * @param _token Address of the ERC20 token to send
+     * @param _recipients Array of recipient addresses
+     * @param _amounts Array of amounts to send to each recipient
+     * @dev The caller must approve this contract to pull the total amount before calling
+     * @dev Arrays must have matching lengths and not exceed ARRAY_LIMIT
+     */
+    function multisendERC20(
+        address _token,
+        address[] calldata _recipients,
+        uint256[] calldata _amounts
+    ) external {
+        uint256 length = _recipients.length;
+        if (length != _amounts.length) revert MismatchedArrays();
+        if (length > ARRAY_LIMIT) revert ArrayLengthExceedsLimit();
+
+        IERC20 token = IERC20(_token);
+
+        uint256 total = 0;
+        for (uint256 i = 0; i < length; ) {
+            unchecked {
+                total += _amounts[i];
+                ++i;
+            }
+        }
+
+        // Pull total amount from caller to contract
+        token.safeTransferFrom(msg.sender, address(this), total);
+
+        // Distribute tokens from contract to recipients
+        for (uint256 i = 0; i < length; ) {
+            token.safeTransfer(_recipients[i], _amounts[i]);
+            unchecked {
+                ++i;
+            }
+        }
+
+        emit Multisended(total);
+    }
+
+    /**
+     * @notice Send ERC20 tokens using transferFrom for each recipient
+     * @param _token Address of the ERC20 token to send
+     * @param _recipients Array of recipient addresses
+     * @param _amounts Array of amounts to send to each recipient
+     * @dev Caller must approve the contract to spend at least the sum of amounts
+     * @dev Uses safeTransferFrom per recipient instead of pulling once and transferring
+     */
+    function multisendERC20From(
+        address _token,
+        address[] calldata _recipients,
+        uint256[] calldata _amounts
+    ) external {
+        uint256 length = _recipients.length;
+        if (length != _amounts.length) revert MismatchedArrays();
+        if (length > ARRAY_LIMIT) revert ArrayLengthExceedsLimit();
+
+        IERC20 token = IERC20(_token);
+
+        uint256 total = 0;
+        for (uint256 i = 0; i < length; ) {
+            token.safeTransferFrom(msg.sender, _recipients[i], _amounts[i]);
+            unchecked {
+                total += _amounts[i];
+                ++i;
+            }
+        }
+
+        emit Multisended(total);
+    }
+
+    /**
+     * @notice Send ERC20 tokens without SafeERC20 helpers (raw transfer/transferFrom)
+     * @param _token Address of the ERC20 token to send
+     * @param _recipients Array of recipient addresses
+     * @param _amounts Array of amounts to send to each recipient
+     * @dev This function uses raw ERC20 calls and may not work with non-standard tokens
+     * @dev Caller must approve the contract to spend at least the sum of amounts
+     */
+    function multisendERC20Unsafe(
+        address _token,
+        address[] calldata _recipients,
+        uint256[] calldata _amounts
+    ) external {
+        uint256 length = _recipients.length;
+        if (length != _amounts.length) revert MismatchedArrays();
+        if (length > ARRAY_LIMIT) revert ArrayLengthExceedsLimit();
+
+        IERC20 token = IERC20(_token);
+
+        uint256 total = 0;
+        for (uint256 i = 0; i < length; ) {
+            unchecked {
+                total += _amounts[i];
+                ++i;
+            }
+        }
+
+        // Pull total amount from caller to contract using raw transferFrom
+        require(token.transferFrom(msg.sender, address(this), total));
+
+        // Distribute tokens from contract to recipients using raw transfer
+        for (uint256 i = 0; i < length; ) {
+            require(token.transfer(_recipients[i], _amounts[i]));
+            unchecked {
+                ++i;
+            }
+        }
+
+        emit Multisended(total);
+    }
+}
+
+

hardhat.config.ts

@@ -5,6 +5,7 @@ import "@nomiclabs/hardhat-ethers";
 import "@nomicfoundation/hardhat-viem";
 import "@nomicfoundation/hardhat-verify";
 import "@nomiclabs/hardhat-waffle";
+import "@nomicfoundation/hardhat-chai-matchers";
 import "hardhat-gas-reporter";
 import dotenv from "dotenv";