Merge 840ef45ca8 into a1bdfc355e

decimal.go

@@ -1513,7 +1513,7 @@ func (d Decimal) StringFixedCash(interval uint8) string {
 	return rounded.string(false)
 }
 
-// Round rounds the decimal to places decimal places (half away from zero).
+// Round rounds the decimal to places decimal places.
 // If places < 0, it will round the integer part to the nearest 10^(-places).
 //
 // Example:
@@ -1544,37 +1544,6 @@ func (d Decimal) Round(places int32) Decimal {
 	return ret
 }
 
-// RoundHalfTowardZero rounds the decimal to places decimal places (half toward zero).
-// If places < 0, it will round the integer part to the nearest 10^(-places).
-//
-// Example:
-//
-//	NewFromFloat(5.45).RoundHalfTowardZero(1).String() // output: "5.4"
-//	NewFromFloat(545).RoundHalfTowardZero(-1).String() // output: "540"
-func (d Decimal) RoundHalfTowardZero(places int32) Decimal {
-	if d.exp == -places {
-		return d
-	}
-	// truncate to places + 1
-	ret := d.rescale(-places - 1)
-
-	// add sign(d) * 0.4
-	if ret.value.Sign() < 0 {
-		ret.value.Sub(ret.value, fourInt)
-	} else {
-		ret.value.Add(ret.value, fourInt)
-	}
-
-	// floor for positive numbers, ceil for negative numbers
-	_, m := ret.value.DivMod(ret.value, tenInt, new(big.Int))
-	ret.exp++
-	if ret.value.Sign() < 0 && m.Cmp(zeroInt) != 0 {
-		ret.value.Add(ret.value, oneInt)
-	}
-
-	return ret
-}
-
 // RoundHalfUp rounds the decimal half towards +infinity.
 //
 // Example:
@@ -1591,7 +1560,7 @@ func (d Decimal) RoundHalfUp(places int32) Decimal {
 	// truncate to places + 1
 	ret := d.rescale(-places - 1)
 
-	// add sign(d) * 0.5 if sign(d) >= 0 else sign(d) * 0.4
+	// add sign(d) * 0.5
 	if ret.value.Sign() < 0 {
 		ret.value.Sub(ret.value, fourInt)
 	} else {
@@ -1624,7 +1593,7 @@ func (d Decimal) RoundHalfDown(places int32) Decimal {
 	// truncate to places + 1
 	ret := d.rescale(-places - 1)
 
-	// add sign(d) * 0.5 if sign(d) < 0 else sign(d) * 0.4
+	// add sign(d) * 0.5
 	if ret.value.Sign() < 0 {
 		ret.value.Sub(ret.value, fiveInt)
 	} else {

decimal_test.go

@@ -3753,32 +3753,3 @@ func TestDecimal_RoundHalfDown(t *testing.T) {
 		})
 	}
 }
-
-func TestDecimal_RoundHalfTowardZero(t *testing.T) {
-	tests := []struct {
-		name   string
-		d      Decimal
-		places int32
-		want   Decimal
-	}{
-		{
-			name:   "5.45",
-			d:      NewFromFloat(5.45),
-			places: 1,
-			want:   NewFromFloat(5.4),
-		},
-		{
-			name:   "545",
-			d:      NewFromInt(545),
-			places: -1,
-			want:   NewFromInt(540),
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			if got := tt.d.RoundHalfTowardZero(tt.places); !got.Equal(tt.want) {
-				t.Errorf("RoundHalfDown() = %v, want %v", got, tt.want)
-			}
-		})
-	}
-}