fix(CL): error blow up in CalcAmount0Delta causes OverChargeSwapOutGivenInError when swapping zero for one

CHANGELOG.md

@@ -45,6 +45,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Bug Fixes
 
 * [#6334](https://github.com/osmosis-labs/osmosis/pull/6334) fix: enable taker fee cli
+* [#6352](https://github.com/osmosis-labs/osmosis/pull/6352) Reduce error blow-up in CalcAmount0Delta by changing the order of math operations.
 
 ### API Breaks
 

osmoutils/osmoassert/assertions.go

@@ -60,9 +60,13 @@ func messageFromMsgAndArgs(msgAndArgs ...interface{}) string {
 	return ""
 }
 
+type Stringer interface {
+	String() string
+}
+
 // Equal compares A with B and asserts that they are equal within tolerance error tolerance
-func Equal[T any](t *testing.T, tolerance osmomath.ErrTolerance, A, B T) {
-	errMsg := fmt.Sprintf("expected %T, actual %T", A, B)
+func Equal[T Stringer](t *testing.T, tolerance osmomath.ErrTolerance, A, B T) {
+	errMsg := fmt.Sprintf("expected %s, actual %s", A.String(), B.String())
 	switch a := any(A).(type) {
 	case osmomath.Int:
 		b, ok := any(B).(osmomath.Int)
@@ -81,5 +85,8 @@ func Equal[T any](t *testing.T, tolerance osmomath.ErrTolerance, A, B T) {
 		failNowIfNot(t, ok)
 
 		require.True(t, tolerance.CompareDec(a, b) == 0, errMsg)
+	default:
+		require.FailNow(t, "unsupported types")
 	}
+
 }

x/concentrated-liquidity/math/math.go

@@ -72,8 +72,7 @@ func CalcAmount0Delta(liq, sqrtPriceA, sqrtPriceB osmomath.BigDec, roundUp bool)
 		// - calculating amountIn during swap
 		// - adding liquidity (request user to provide more tokens in in favor of the pool)
 		// The denominator is truncated to get a higher final amount.
-		denom := sqrtPriceA.MulTruncate(sqrtPriceB)
-		return liq.Mul(diff).QuoMut(denom).Ceil()
+		return liq.MulRoundUp(diff).QuoTruncate(sqrtPriceA).QuoTruncate(sqrtPriceB).Ceil()
 	}
 	// These are truncated at precision end to round in favor of the pool when:
 	// - calculating amount out during swap

x/concentrated-liquidity/math/math_test.go

@@ -158,6 +158,22 @@ func TestCalcAmount0Delta(t *testing.T) {
 			amount0Expected: osmomath.MustNewBigDecFromStr("6098022989717817431593106314408.88812810159039320984467945943").Ceil(), // rounded up at precision end.
 			isWithTolerance: true,
 		},
+		// See: https://github.com/osmosis-labs/osmosis/issues/6351 for details.
+		// The values were taken from the failing swap on the development branch that reproduced the issue.
+		"edge case: low sqrt prices may cause error amplofication if incorrect order of operations": {
+			// from decimal import *
+			// from math import *
+			// getcontext().prec = 100
+			// max_sqrt_p = Decimal("0.00000099994999874993749609347654199")
+			// min_sqrt_p = Decimal("0.000000000000001409841835100661211756")
+			// liq = Decimal("5000252259822539816806336.971796256914465071095518135400579243")
+			// liq * (max_sqrt_p - min_sqrt_p) / (max_sqrt_p * min_sqrt_p)
+			liquidity:       osmomath.MustNewBigDecFromStr("5000252259822539816806336.971796256914465071095518135400579243"),
+			sqrtPA:          osmomath.MustNewBigDecFromStr("0.00000099994999874993749609347654199"),
+			sqrtPB:          osmomath.MustNewBigDecFromStr("0.000000000000001409841835100661211756"),
+			roundUp:         true,
+			amount0Expected: osmomath.MustNewBigDecFromStr("3546676037185128488234786333758360815266.999539026068480181194797910898392880").Ceil(),
+		},
 	}
 
 	for name, tc := range testCases {