vendor tsgo

tools/tsgo/internal/jsnum/pseudobigint.go

@@ -0,0 +1,66 @@
+package jsnum
+
+import (
+	"fmt"
+	"math/big"
+	"strings"
+)
+
+// PseudoBigInt represents a JS-like bigint. The zero state of the struct represents the value 0.
+type PseudoBigInt struct {
+	Negative    bool   // true if the value is a non-zero negative number.
+	Base10Value string // The absolute value in base 10 with no leading zeros. The value zero is represented as an empty string.
+}
+
+func NewPseudoBigInt(value string, negative bool) PseudoBigInt {
+	value = strings.TrimLeft(value, "0")
+	return PseudoBigInt{Negative: negative && len(value) != 0, Base10Value: value}
+}
+
+func (value PseudoBigInt) String() string {
+	if len(value.Base10Value) == 0 {
+		return "0"
+	}
+	if value.Negative {
+		return "-" + value.Base10Value
+	}
+	return value.Base10Value
+}
+
+func (value PseudoBigInt) Sign() int {
+	if len(value.Base10Value) == 0 {
+		return 0
+	}
+	if value.Negative {
+		return -1
+	}
+	return 1
+}
+
+func ParseValidBigInt(text string) PseudoBigInt {
+	text, negative := strings.CutPrefix(text, "-")
+	return NewPseudoBigInt(ParsePseudoBigInt(text), negative)
+}
+
+func ParsePseudoBigInt(stringValue string) string {
+	stringValue = strings.TrimSuffix(stringValue, "n")
+	var b1 byte
+	if len(stringValue) > 1 {
+		b1 = stringValue[1]
+	}
+	switch b1 {
+	case 'b', 'B', 'o', 'O', 'x', 'X':
+		// Not decimal.
+	default:
+		stringValue = strings.TrimLeft(stringValue, "0")
+		if stringValue == "" {
+			return "0"
+		}
+		return stringValue
+	}
+	bi, ok := new(big.Int).SetString(stringValue, 0)
+	if !ok {
+		panic(fmt.Sprintf("Failed to parse big int: %q", stringValue))
+	}
+	return bi.String() // !!!
+}