Return a copy of big.Int

pkg/source/limitorder/pool_simulator.go

@@ -328,12 +328,12 @@ func (p *PoolSimulator) calcMakerAssetFeeAmount(order *order, filledMakingAmount
 // given total takingAmount, calculate fee and takingAmountAfterFee
 func (p *PoolSimulator) calcTakerAssetFeeAmountExactIn(order *order, takingAmount *big.Int) (takingAmountAfterFee *big.Int, fee *big.Int) {
 	if !order.IsTakerAssetFee {
-		return takingAmount, big.NewInt(0)
+		return new(big.Int).Set(takingAmount), big.NewInt(0)
 	}
 
 	feePct := order.MakerTokenFeePercent // reuse same field
 	if feePct == 0 {
-		return takingAmount, big.NewInt(0)
+		return new(big.Int).Set(takingAmount), big.NewInt(0)
 	}
 
 	// fee = ceiling(takingAmountAfterFee * feePct / BasisPoint)
@@ -354,12 +354,12 @@ func (p *PoolSimulator) calcTakerAssetFeeAmountExactIn(order *order, takingAmoun
 // given filled takingAmountAfterFee, calculate fee and total takingAmount
 func (p *PoolSimulator) calcTakerAssetFeeAmountExactOut(order *order, takingAmountAfterFee *big.Int) (takingAmount *big.Int, fee *big.Int) {
 	if !order.IsTakerAssetFee {
-		return takingAmountAfterFee, big.NewInt(0)
+		return new(big.Int).Set(takingAmountAfterFee), big.NewInt(0)
 	}
 
 	feePct := order.MakerTokenFeePercent // reuse same field
 	if feePct == 0 {
-		return takingAmountAfterFee, big.NewInt(0)
+		return new(big.Int).Set(takingAmountAfterFee), big.NewInt(0)
 	}
 
 	amount := new(big.Int).Mul(takingAmountAfterFee, big.NewInt(int64(feePct)))

pkg/source/limitorder/pool_simulator_calc_amount_in.go

@@ -145,12 +145,12 @@ func (p *PoolSimulator) calcAmountInWithSwapInfo(swapSide SwapSide, tokenAmountO
 // input is the received amount after fee.
 func (p *PoolSimulator) calcMakerAssetAmountBeforeFee(order *order, makingAmount *big.Int) (makingAmountBeforeFee *big.Int, fee *big.Int) {
 	if order.IsTakerAssetFee {
-		return makingAmount, big.NewInt(0)
+		return new(big.Int).Set(makingAmount), big.NewInt(0)
 	}
 
 	feePct := order.MakerTokenFeePercent
 	if feePct == 0 {
-		return makingAmount, big.NewInt(0)
+		return new(big.Int).Set(makingAmount), big.NewInt(0)
 	}
 
 	// makingAmountBeforeFee = makingAmount * BasisPoint / (BasisPoint - feePct)
@@ -167,8 +167,7 @@ func (p *PoolSimulator) calcMakerAssetAmountBeforeFee(order *order, makingAmount
 
 func divCeil(a, b *big.Int) *big.Int {
 	// (a + b - 1) / b
-	return new(big.Int).Div(
-		new(big.Int).Sub(new(big.Int).Add(a, b), big.NewInt(1)),
-		b,
-	)
+	a = new(big.Int).Add(a, b)
+	a = new(big.Int).Sub(a, big.NewInt(1))
+	return a.Div(a, b)
 }