Refactor approveAndCall logic into the BaseTransfer module

argentlabs · Apr 3, 2020 · 3d51aab · 3d51aab
1 parent 52df688
commit 3d51aab
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Showing 3 changed files with 56 additions and 34 deletions.
diff --git a/contracts/modules/ApprovedTransfer.sol b/contracts/modules/ApprovedTransfer.sol
@@ -29,15 +29,6 @@ import "../../lib/other/ERC20.sol";
 contract ApprovedTransfer is BaseModule, RelayerModuleV2, BaseTransfer {
 
     bytes32 constant NAME = "ApprovedTransfer";
-    event ApprovedAndCalledContract(
-        address indexed wallet,
-        address indexed to,
-        address spender,
-        address indexed token,
-        uint256 amountApproved,
-        uint256 amountSpent,
-        bytes data
-    );
 
     constructor(ModuleRegistry _registry, GuardianStorage _guardianStorage) BaseModule(_registry, _guardianStorage, NAME) public {
 
@@ -110,29 +101,7 @@ contract ApprovedTransfer is BaseModule, RelayerModuleV2, BaseTransfer {
         onlyWhenUnlocked(_wallet)
     {
         require(!_wallet.authorised(_contract) && _contract != address(_wallet), "AT: Forbidden contract");
-        uint256 currentAllowance = ERC20(_token).allowance(address(_wallet), _spender);
-
-        // Approve the desired amount
-        bytes memory methodData = abi.encodeWithSignature("approve(address,uint256)", _spender, _amount);
-        invokeWallet(address(_wallet), _token, 0, methodData);
-
-        invokeWallet(address(_wallet), _contract, 0, _data);
-
-        uint256 unusedAllowance = ERC20(_token).allowance(address(_wallet), _spender);
-        uint256 usedAllowance = SafeMath.sub(_amount, unusedAllowance);
-
-        // Restore the original allowance amount
-        methodData = abi.encodeWithSignature("approve(address,uint256)", _spender, currentAllowance);
-        invokeWallet(address(_wallet), _token, 0, methodData);
-
-        emit ApprovedAndCalledContract(
-            address(_wallet),
-            _contract,
-            _spender,
-            _token,
-            _amount,
-            usedAllowance,
-            _data);
+        doApproveTokenAndCallContract(_wallet, _token, _spender, _amount, _contract, _data);
     }
 
     // *************** Implementation of RelayerModule methods ********************* //

diff --git a/contracts/modules/common/BaseTransfer.sol b/contracts/modules/common/BaseTransfer.sol
@@ -32,7 +32,15 @@ contract BaseTransfer is BaseModule {
     event Transfer(address indexed wallet, address indexed token, uint256 indexed amount, address to, bytes data);
     event Approved(address indexed wallet, address indexed token, uint256 amount, address spender);
     event CalledContract(address indexed wallet, address indexed to, uint256 amount, bytes data);
-
+    event ApprovedAndCalledContract(
+        address indexed wallet,
+        address indexed to,
+        address spender,
+        address indexed token,
+        uint256 amountApproved,
+        uint256 amountSpent,
+        bytes data
+    );
     // *************** Internal Functions ********************* //
 
     /**
@@ -77,4 +85,48 @@ contract BaseTransfer is BaseModule {
         invokeWallet(address(_wallet), _contract, _value, _data);
         emit CalledContract(address(_wallet), _contract, _value, _data);
     }
+
+    /**
+    * @dev Helper method to call an external contract.
+    * @param _wallet The target wallet.
+    * @param _token The ERC20 address.
+    * @param _spender The spender address.
+    * @param _amount The amount of tokens to transfer.
+    * @param _contract The contract address.
+    * @param _data The method data.
+    */
+    function doApproveTokenAndCallContract(
+        BaseWallet _wallet,
+        address _token,
+        address _spender,
+        int256 _amount,
+        address _contract,
+        bytes memory _data
+    )
+        internal
+    {
+        uint256 currentAllowance = ERC20(_token).allowance(address(_wallet), _spender);
+
+        // Approve the desired amount
+        bytes memory methodData = abi.encodeWithSignature("approve(address,uint256)", _spender, _amount);
+        invokeWallet(address(_wallet), _token, 0, methodData);
+
+        invokeWallet(address(_wallet), _contract, 0, _data);
+
+        uint256 unusedAllowance = ERC20(_token).allowance(address(_wallet), _spender);
+        uint256 usedAllowance = SafeMath.sub(_amount, unusedAllowance);
+
+        // Restore the original allowance amount
+        methodData = abi.encodeWithSignature("approve(address,uint256)", _spender, currentAllowance);
+        invokeWallet(address(_wallet), _token, 0, methodData);
+
+        emit ApprovedAndCalledContract(
+            address(_wallet),
+            _contract,
+            _spender,
+            _token,
+            _amount,
+            usedAllowance,
+            _data);
+    }
 }
diff --git a/test/approvedTransfer.js b/test/approvedTransfer.js
@@ -317,7 +317,8 @@ describe("Approved Transfer", function () {
           const allowanceBefore = await erc20.allowance(wallet.contractAddress, consumer);
           const balanceBefore = await erc20.balanceOf(contract.contractAddress);
 
-          dataToTransfer = contract.contract.interface.functions.setStateAndPayTokenWithConsumer.encode([2, erc20.contractAddress, amountToApprove]);
+          const dataToTransfer = contract.contract.interface.functions
+            .setStateAndPayTokenWithConsumer.encode([2, erc20.contractAddress, amountToApprove]);
           await manager.relay(approvedTransfer, "approveTokenAndCallContract",
             [wallet.contractAddress, erc20.contractAddress, consumer, amountToApprove, contract.contractAddress, dataToTransfer],
             wallet, [owner, ...sortWalletByAddress([guardian1, guardian2])]);