From 582973955b33c8b4641dbd27377e73317f3c422f Mon Sep 17 00:00:00 2001
From: Oumar <o_fall@orange.fr>
Date: Tue, 15 Aug 2023 15:04:10 +0200
Subject: [PATCH 1/3] fix: Borrow capacity computation

---
 src/MorphoAaveV3DataHolder.ts           | 2 +-
 src/simulation/MorphoAaveV3Simulator.ts | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/MorphoAaveV3DataHolder.ts b/src/MorphoAaveV3DataHolder.ts
index 233ba04..660f866 100644
--- a/src/MorphoAaveV3DataHolder.ts
+++ b/src/MorphoAaveV3DataHolder.ts
@@ -106,7 +106,7 @@ export class MorphoAaveV3DataHolder {
         );
 
         borrowCapacity = borrowCapacity.add(
-          PercentMath.percentMul(
+          this.__MATH__.percentMulDown(
             collateralReduced,
             marketConfig.borrowableFactor
           )
diff --git a/src/simulation/MorphoAaveV3Simulator.ts b/src/simulation/MorphoAaveV3Simulator.ts
index 4480414..fad4f41 100644
--- a/src/simulation/MorphoAaveV3Simulator.ts
+++ b/src/simulation/MorphoAaveV3Simulator.ts
@@ -796,7 +796,8 @@ export class MorphoAaveV3Simulator extends MorphoAaveV3DataEmitter {
         operation
       );
 
-    const totalCollateral = userMarketData.totalCollateral.add(amount);
+    // Since it's gonna be scaled and unscaled, the value is gonna be reduced by one
+    const totalCollateral = userMarketData.totalCollateral.add(amount.sub(1));
 
     const newUserMarketData: UserMarketData = {
       ...userMarketData,

From afacad7706ce9e84f6e2676987f79df44bb19508 Mon Sep 17 00:00:00 2001
From: Oumar <o_fall@orange.fr>
Date: Tue, 15 Aug 2023 15:19:09 +0200
Subject: [PATCH 2/3] test: update tests

---
 tests/units/computeUserData.test.ts | 2 +-
 tests/units/simulator.test.ts       | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/tests/units/computeUserData.test.ts b/tests/units/computeUserData.test.ts
index 8e05f03..3768a47 100644
--- a/tests/units/computeUserData.test.ts
+++ b/tests/units/computeUserData.test.ts
@@ -131,7 +131,7 @@ describe("computeUserData", () => {
           .div(underlyingUnit);
 
         expectedBorrowCapacity = expectedBorrowCapacity.add(
-          PercentMath.percentMul(
+          __MATHS__.percentMulDown(
             userCollateralUSD.mul(LT_LOWER_BOUND.sub(1)).div(LT_LOWER_BOUND), // the borrow capacity is reduced by a small amount
             borrowableFactor
           )
diff --git a/tests/units/simulator.test.ts b/tests/units/simulator.test.ts
index 11fec19..153edd8 100644
--- a/tests/units/simulator.test.ts
+++ b/tests/units/simulator.test.ts
@@ -189,9 +189,9 @@ describe("Simulator", () => {
       ]);
       await sleep(100);
 
-      const finalTotalCollateral = initialTotalCollateral.add(
-        supplyCollateralAmount
-      );
+      const finalTotalCollateral = initialTotalCollateral
+        .add(supplyCollateralAmount)
+        .sub(1);
       expect(totalCollateral).toBnEq(finalTotalCollateral);
     });
 
@@ -267,7 +267,7 @@ describe("Simulator", () => {
         TransactionType.borrow
       )!.amount;
 
-      const expectedBorrowCapacity = BigNumber.from("717673393785148514851485");
+      const expectedBorrowCapacity = BigNumber.from("717673393785138613861386");
       expect(initialBorrowCapacity).toBnEq(expectedBorrowCapacity);
 
       simulator.simulate([

From 2c9b22384e262c1b6e75cdb8afc706a7de076bf5 Mon Sep 17 00:00:00 2001
From: Oumar <o_fall@orange.fr>
Date: Tue, 15 Aug 2023 16:06:22 +0200
Subject: [PATCH 3/3] test: update e2e tests

---
 tests/e2e/bulker.test.ts | 4 ++--
 tests/helpers/bn.ts      | 8 ++++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/tests/e2e/bulker.test.ts b/tests/e2e/bulker.test.ts
index 4631f64..f95fead 100644
--- a/tests/e2e/bulker.test.ts
+++ b/tests/e2e/bulker.test.ts
@@ -541,8 +541,8 @@ describe("MorphoAaveV3 Bulker", () => {
         weth.address,
         morphoUser.address
       );
-      expect(ma3Balance).to.equal(
-        amountToBorrow,
+      expect(
+        approxEqual(ma3Balance, amountToBorrow, 1),
         `expected ma3 weth balance is ${amountToBorrow}, received ${ma3Balance}`
       );
 
diff --git a/tests/helpers/bn.ts b/tests/helpers/bn.ts
index 194b81f..17dedc9 100644
--- a/tests/helpers/bn.ts
+++ b/tests/helpers/bn.ts
@@ -2,8 +2,12 @@ import { BigNumber, BigNumberish } from "ethers";
 
 const APPROX_EQUAL_THRESHOLD = 10;
 
-export const approxEqual = (a: BigNumberish, b: BigNumberish) => {
+export const approxEqual = (
+  a: BigNumberish,
+  b: BigNumberish,
+  delta = APPROX_EQUAL_THRESHOLD
+) => {
   a = BigNumber.from(a);
   b = BigNumber.from(b);
-  return a.sub(b).abs().lte(APPROX_EQUAL_THRESHOLD);
+  return a.sub(b).abs().lte(delta);
 };