From d60ed5a947ec259fb1a9b125561c0262dc62b08c Mon Sep 17 00:00:00 2001
From: jtfirek <firekjt@gmail.com>
Date: Wed, 16 Oct 2024 10:38:23 -0500
Subject: [PATCH] discount pricing function

---
 src/Liquifier.sol    | 14 +++++++++-----
 test/Liquifier.t.sol |  4 ++++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/Liquifier.sol b/src/Liquifier.sol
index 90bdb0ee..ddc84dbf 100644
--- a/src/Liquifier.sol
+++ b/src/Liquifier.sol
@@ -168,11 +168,8 @@ contract Liquifier is Initializable, UUPSUpgradeable, OwnableUpgradeable, Pausab
 
         // The L1SyncPool's `_anticipatedDeposit` should be the only place to mint the `token` and always send its entirety to the Liquifier contract
         if(tokenInfos[_token].isL2Eth) _L2SanityChecks(_token);
-
-        uint256 dx = quoteByMarketValue(_token, _amount);
-
-        // discount
-        dx = (10000 - tokenInfos[_token].discountInBasisPoints) * dx / 10000;
+    
+        uint256 dx = quoteByDiscountedValue(_token, _amount);
         require(!isDepositCapReached(_token, dx), "CAPPED");
 
         uint256 eEthShare = liquidityPool.depositToRecipient(msg.sender, dx, _referral);
@@ -420,6 +417,13 @@ contract Liquifier is Initializable, UUPSUpgradeable, OwnableUpgradeable, Pausab
         revert NotSupportedToken();
     }
 
+    // Calculates the amount of eETH that will be minted for a given token considering the discount rate
+    function quoteByDiscountedValue(address _token, uint256 _amount) public view returns (uint256) {
+        uint256 marketValue = quoteByMarketValue(_token, _amount);
+
+        return (10000 - tokenInfos[_token].discountInBasisPoints) * marketValue / 10000;
+    }
+
     function verifyQueuedWithdrawal(address _user, IDelegationManager.Withdrawal calldata _queuedWithdrawal) public view returns (bytes32) {
         require(_queuedWithdrawal.staker == _user && _queuedWithdrawal.withdrawer == address(this), "wrong depositor/withdrawer");
         for (uint256 i = 0; i < _queuedWithdrawal.strategies.length; i++) {
diff --git a/test/Liquifier.t.sol b/test/Liquifier.t.sol
index 7f6936d7..31ad5782 100644
--- a/test/Liquifier.t.sol
+++ b/test/Liquifier.t.sol
@@ -97,6 +97,10 @@ contract LiquifierTest is TestSetup {
         vm.stopPrank();
 
         assertApproxEqAbs(eETHInstance.balanceOf(alice), 10 ether - 0.5 ether, 0.1 ether);
+
+        uint256 aliceQuotedEETH = liquifierInstance.quoteByDiscountedValue(address(stEth), 10 ether);
+        // alice will actually receive 1 wei less due to the infamous 1 wei rounding corner case
+        assertApproxEqAbs(eETHInstance.balanceOf(alice), aliceQuotedEETH, 1);
     }
 
     function test_deopsit_stEth_and_swap() internal {