golang win1251 <-> utf8 encoding issue demonstration

main.go

package main

import (
	"fmt"
	"golang.org/x/text/encoding/charmap"
)

func main() {
	for i := 0; i <= 255; i++ {
		charnum := uint8(i)
		orig := []uint8{charnum}
		utf8 := DecodeWindows1251(orig)
		win1251 := EncodeWindows1251(utf8)
		if string(orig) != string(win1251) {
			fmt.Printf("Oh~.. Failed at charnum 0x%x\n", i)
			fmt.Printf("(orig, utf8, win1251)\n")
			fmt.Printf("string: %s, %s, %s\n", string(orig), string(utf8), string(win1251))
			fmt.Printf("quoted: %+q, %+q, %+q\n", string(orig), string(utf8), string(win1251))
			fmt.Printf("hex   : % x, % x, % x\n", string(orig), string(utf8), string(win1251))
		}
	}
}

func DecodeWindows1251(ba []uint8) []uint8 {
	dec := charmap.Windows1251.NewDecoder()
	out, _ := dec.Bytes(ba)
	return out
}

func EncodeWindows1251(ba []uint8) []uint8 {
	enc := charmap.Windows1251.NewEncoder()
	out, _ := enc.String(string(ba))
	return []uint8(out)
}