Introduce ERC20Farm remaining after claim for non-precise implementat…

…ions
1inch · Nov 27, 2021 · 84fd5ed · 84fd5ed
1 parent b778663
commit 84fd5ed
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Showing 3 changed files with 16 additions and 9 deletions.
diff --git a/contracts/ERC20Farm.sol b/contracts/ERC20Farm.sol
@@ -17,9 +17,12 @@ contract ERC20Farm is IERC20Farm, FarmAccounting {
         FarmAccounting(stakingToken_, rewardsToken_)
     {}  // solhint-disable-line no-empty-blocks
 
-    function claimFor(address account, uint256 amount) external override {
+    function claimFor(address account, uint256 amount) external override returns(uint256 remaining) {
         require(msg.sender == address(stakingToken), "ERC20: Access denied");
-        rewardsToken.safeTransfer(account, amount);
+
+        uint256 claimable = Math.min(amount, rewardsToken.balanceOf(address(this)));
+        rewardsToken.safeTransfer(account, claimable);
+        return amount - claimable;
     }
 
     function _updateFarmingState() internal override {

diff --git a/contracts/ERC20Farmable.sol b/contracts/ERC20Farmable.sol
@@ -83,12 +83,16 @@ abstract contract ERC20Farmable is ERC20, IERC20Farmable {
         uint256 balance = balanceOf(msg.sender);
 
 
-        try farm_.claimFor(msg.sender, _farmed(farm_, msg.sender, balance, fpt)) {
-            if (_userFarms[msg.sender].contains(address(farm_))) {
-                userCorrection[farm_][msg.sender] = -int256(balance * fpt);
-            }
-            else {
-                userCorrection[farm_][msg.sender] = 0;
+        try farm_.claimFor(msg.sender, _farmed(farm_, msg.sender, balance, fpt)) returns(uint256 remaining) {
+            if (remaining <= 1e36) {
+                if (_userFarms[msg.sender].contains(address(farm_))) {
+                    userCorrection[farm_][msg.sender] = -int256(balance * fpt + remaining * 1e18);
+                }
+                else {
+                    userCorrection[farm_][msg.sender] = -int256(remaining * 1e18);
+                }
+            } else {
+                emit Error("farm.claimFor() result overflowed");
             }
         }
         catch {

diff --git a/contracts/interfaces/IERC20Farm.sol b/contracts/interfaces/IERC20Farm.sol
@@ -5,5 +5,5 @@ pragma solidity ^0.8.0;
 import "./IFarmAccounting.sol";
 
 interface IERC20Farm is IFarmAccounting {
-    function claimFor(address account, uint256 amount) external;
+    function claimFor(address account, uint256 amount) external returns(uint256 remaining);
 }