Add Compound error return (Spearbit #33)

src/compound/MorphoGovernance.sol

@@ -112,8 +112,8 @@ abstract contract MorphoGovernance is MorphoUtils {
 
     /// ERRORS ///
 
-    /// @notice Thrown when the creation of a market failed on Compound.
-    error MarketCreationFailedOnCompound();
+    /// @notice Thrown when the creation of a market failed on Compound and kicks back Compound error code.
+    error MarketCreationFailedOnCompound(uint256 errorCode);
 
     /// @notice Thrown when the input is above the max basis points value (100%).
     error ExceedsMaxBasisPoints();
@@ -440,7 +440,7 @@ abstract contract MorphoGovernance is MorphoUtils {
         address[] memory marketToEnter = new address[](1);
         marketToEnter[0] = _poolToken;
         uint256[] memory results = comptroller.enterMarkets(marketToEnter);
-        if (results[0] != 0) revert MarketCreationFailedOnCompound();
+        if (results[0] != 0) revert MarketCreationFailedOnCompound(results[0]);
 
         // Same initial index as Compound.
         uint256 initialIndex;

src/compound/PositionsManager.sol

@@ -125,17 +125,17 @@ contract PositionsManager is IPositionsManager, MatchingEngine {
     /// @notice Thrown when the amount repaid during the liquidation is above what is allowed to be repaid.
     error AmountAboveWhatAllowedToRepay();
 
-    /// @notice Thrown when the borrow on Compound failed.
-    error BorrowOnCompoundFailed();
+    /// @notice Thrown when the borrow on Compound failed and throws back the Compound error code.
+    error BorrowOnCompoundFailed(uint256 errorCode);
 
-    /// @notice Thrown when the redeem on Compound failed .
-    error RedeemOnCompoundFailed();
+    /// @notice Thrown when the redeem on Compound failed and throws back the Compound error code.
+    error RedeemOnCompoundFailed(uint256 errorCode);
 
-    /// @notice Thrown when the repay on Compound failed.
-    error RepayOnCompoundFailed();
+    /// @notice Thrown when the repay on Compound failed and throws back the Compound error code.
+    error RepayOnCompoundFailed(uint256 errorCode);
 
-    /// @notice Thrown when the mint on Compound failed.
-    error MintOnCompoundFailed();
+    /// @notice Thrown when the mint on Compound failed and throws back the Compound error code.
+    error MintOnCompoundFailed(uint256 errorCode);
 
     /// @notice Thrown when user is not a member of the market.
     error UserNotMemberOfMarket();
@@ -926,7 +926,8 @@ contract PositionsManager is IPositionsManager, MatchingEngine {
             ICEther(_poolToken).mint{value: _amount}();
         } else {
             _underlyingToken.safeApprove(_poolToken, _amount);
-            if (ICToken(_poolToken).mint(_amount) != 0) revert MintOnCompoundFailed();
+            uint256 errorCode = ICToken(_poolToken).mint(_amount);
+            if (errorCode != 0) revert MintOnCompoundFailed(errorCode);
         }
     }
 
@@ -936,15 +937,20 @@ contract PositionsManager is IPositionsManager, MatchingEngine {
     function _withdrawFromPool(address _poolToken, uint256 _amount) internal {
         // Withdraw only what is possible. The remaining dust is taken from the contract balance.
         _amount = CompoundMath.min(ICToken(_poolToken).balanceOfUnderlying(address(this)), _amount);
-        if (ICToken(_poolToken).redeemUnderlying(_amount) != 0) revert RedeemOnCompoundFailed();
+
+        uint256 errorCode = ICToken(_poolToken).redeemUnderlying(_amount);
+        if (errorCode != 0) revert RedeemOnCompoundFailed(errorCode);
+
         if (_poolToken == cEth) IWETH(address(wEth)).deposit{value: _amount}(); // Turn the ETH received in wETH.
     }
 
     /// @dev Borrows underlying tokens from Compound.
     /// @param _poolToken The address of the pool token.
     /// @param _amount The amount of token (in underlying).
     function _borrowFromPool(address _poolToken, uint256 _amount) internal {
-        if ((ICToken(_poolToken).borrow(_amount) != 0)) revert BorrowOnCompoundFailed();
+        uint256 errorCode = ICToken(_poolToken).borrow(_amount);
+        if (errorCode != 0) revert BorrowOnCompoundFailed(errorCode);
+
         if (_poolToken == cEth) IWETH(address(wEth)).deposit{value: _amount}(); // Turn the ETH received in wETH.
     }
 
@@ -969,7 +975,8 @@ contract PositionsManager is IPositionsManager, MatchingEngine {
                 ICEther(_poolToken).repayBorrow{value: _amount}();
             } else {
                 _underlyingToken.safeApprove(_poolToken, _amount);
-                if (ICToken(_poolToken).repayBorrow(_amount) != 0) revert RepayOnCompoundFailed();
+                uint256 errorCode = ICToken(_poolToken).repayBorrow(_amount);
+                if (errorCode != 0) revert RepayOnCompoundFailed(errorCode);
             }
         }
     }

test/compound/TestGovernance.t.sol

@@ -20,7 +20,7 @@ contract TestGovernance is TestSetup {
     function testShouldRevertWhenCreatingMarketWithAnImproperMarket() public {
         Types.MarketParameters memory marketParams = Types.MarketParameters(3_333, 0);
 
-        hevm.expectRevert(abi.encodeWithSignature("MarketCreationFailedOnCompound()"));
+        hevm.expectRevert(abi.encodeWithSignature("MarketCreationFailedOnCompound(uint256)", 9));
         morpho.createMarket(address(supplier1), marketParams);
     }