Fix/srm (#358)

.gitmodules

@@ -8,6 +8,7 @@
 [submodule "lib/chainlink"]
 	path = lib/chainlink
 	url = https://github.com/smartcontractkit/chainlink
+	ignore = untracked
 [submodule "lib/openzeppelin-contracts-upgradeable"]
 	path = lib/openzeppelin-contracts-upgradeable
 	url = https://github.com/openzeppelin/openzeppelin-contracts-upgradeable

scripts/deploy-perp-only-market.s.sol

@@ -71,7 +71,6 @@ contract DeployPerpOnlyMarket is Utils {
       PMRM(_getContract("BTC", "pmrm")).setWhitelistedCallee(address(market.iapFeed), true);
       PMRM(_getContract("BTC", "pmrm")).setWhitelistedCallee(address(market.ibpFeed), true);
       PMRM(_getContract("BTC", "pmrm")).setWhitelistedCallee(address(market.perpFeed), true);
-
     } else {
       _transferOwner(market, vm.envAddress("MAINNET_OWNER"));
     }

src/risk-managers/StandardManager.sol

@@ -306,8 +306,8 @@ contract StandardManager is IStandardManager, ILiquidatableManager, BaseManager,
             riskAdding = true;
           }
         }
-      } else if (detail.assetType == AssetType.Option) {
-        // if the user is shorting more options, we need to check margin
+      } else {
+        // if the user is shorting more options, or removing collateral, we need to check margin
         if (assetDeltas[i].delta < 0) {
           riskAdding = true;
         }

test/deploy-lrt-market-fork.t.sol

@@ -1,4 +1,4 @@
-pragma solidity 0.8.20;
+pragma solidity ^0.8.18;
 
 import "forge-std/console.sol";
 import "../scripts/types.sol";

test/risk-managers/unit-tests/StandardManager/TestStandardManager_Misc.t.sol

@@ -57,6 +57,28 @@ contract UNIT_TestStandardManager_Misc is TestStandardManagerBase {
     assertEq(_getCashBalance(bobAcc), -int(btcSpot / 2));
   }
 
+  function testCannotWithdrawBaseIfNegativeCash() public {
+    manager.setBorrowingEnabled(true);
+    cash.deposit(aliceAcc, uint(50000e18));
+
+    // can only borrow 50% of base asset's value
+    manager.setBaseAssetMarginFactor(btcMarketId, 0.5e18, 1e18);
+
+    // bob deposit 1 WBTC
+    wbtc.mint(address(this), 1e18);
+    wbtc.approve(address(wbtcAsset), 1e18);
+    wbtcAsset.deposit(bobAcc, uint(1e18));
+
+    vm.startPrank(bob);
+    // bob can borrow against this spot asset
+    cash.withdraw(bobAcc, uint(btcSpot / 2), bob);
+
+    assertEq(_getCashBalance(bobAcc), -int(btcSpot / 2));
+
+    vm.expectRevert(IStandardManager.SRM_PortfolioBelowMargin.selector);
+    wbtcAsset.withdraw(bobAcc, uint(1e18), bob);
+  }
+
   function testCannotTradeMoreThanMaxAccountSize() public {
     manager.setMaxAccountSize(10);