You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: builtin_json.go
    path of file: ./repos/go-starter-kit/vendor/github.com/dop251/goja
    
    the code of the file until where you have to start completion: package goja

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"math"
	"strings"
)

var hex = "0123456789a
    
func (r *Runtime) builtinJSON_stringify(call FunctionCall) Value {
	ctx := _builtinJSON_stringifyContext{
		r: r,
	}

	replacer, _ := call.Argument(1).(*Object)
	if replacer != nil {
		if isArray(replacer) {
			length := replacer.self.getStr("length").ToInteger()
			seen := map[string]bool{}
			propertyList := make([]Value, length)
			length = 0
			for index := range propertyList {
				var name string
				value := replacer.self.get(intToValue(int64(index)))
				if s, ok := value.assertString(); ok {
					name = s.String()
				} else if _, ok := value.assertInt(); ok {
					name = value.String()
				} else if _, ok := value.assertFloat(); ok {
					name = value.String()
				} else if o, ok := value.(*Object); ok {
					switch o.self.className() {
					case classNumber, classString:
						name = value.String()
					}
				}
				if seen[name] {
					continue
				}
				seen[name] = true
				length += 1
				propertyList[index] = newStringValue(name)
			}
			ctx.propertyList = propertyList[0:length]
		} else if c, ok := replacer.self.assertCallable(); ok {
			ctx.replacerFunction = c
		}
	}
	if spaceValue := call.Argument(2); spaceValue != _undefined {
		if o, ok := spaceValue.(*Object); ok {
			switch o := o.self.(type) {
			case *primitiveValueObject:
				spaceValue = o.pValue
			case *stringObject:
				spaceValue = o.value
			}
		}
		isNum := false
		var num int64
		num, isNum = spaceValue.assertInt()
		if !isNum {
			if f, ok := spaceValue.assertFloat(); ok {
				num = int64(f)
				isNum = true
			}
		}
		if isNum {
			if num > 0 {
				if num > 10 {
					num = 10
				}
				ctx.gap = strings.Repeat(" ", int(num))
			}
		} else {
			if s, ok := spaceValue.assertString(); ok {
				str := s.String()
				if len(str) > 10 {
					ctx.gap = str[:10]
				} else {
					ctx.gap = str
				}
			}
		}
	}

	if ctx.do(call.Argument(0)) {
		return newStringValue(ctx.buf.String())
	}
	return _undefined
}