that is, runes. (This differs from C's printf where the
units are always measured in bytes.) Either or both of the flags
may be replaced with the character '*', causing their values to be
obtained from the next operand (preceding the one to format),
which must be of type int.

For most values, width is the minimum number of runes to output,
padding the formatted form with spaces if necessary.

}

var sinkInt int

func BenchmarkRuneCount(b *testing.B) {
	// Each sub-benchmark counts the runes in a string in a different way.
	b.Run("lenruneslice", func(b *testing.B) {
		for _, sd := range stringdata {
			b.Run(sd.name, func(b *testing.B) {
				for i := 0; i < b.N; i++ {
					sinkInt += len([]rune(sd.data))
				}
			})
		}
	})
	b.Run("rangeloop", func(b *testing.B) {

	// So limit the buffer to 16000 characters. This number was
	// discovered by experimenting with syscall.WriteConsole.
	const maxWrite = 16000
	for len(runes) > 0 {
		m := len(runes)
		if m > maxWrite {
			m = maxWrite
		}
		chunk := runes[:m]
		runes = runes[m:]
		uint16s := utf16.Encode(chunk)
		for len(uint16s) > 0 {
			var written uint32

// The text itself is stored in a separate buffer; cell only describes the
// segment's size in bytes, its width in runes, and whether it's an htab
// ('\t') terminated cell.
type cell struct {
	size  int  // cell size in bytes
	width int  // cell width in runes
	htab  bool // true if the cell is terminated by an htab ('\t')
}

// A Writer is a filter that inserts padding around tab-delimited

// TODO(rfindley): this should not be necessary.
func sanitizeObjectString(s string) string {
	var runes []rune
	for _, r := range s {
		if '₀' <= r && r < '₀'+10 {
			continue // trim type parameter subscripts
		}
		runes = append(runes, r)
	}
	return string(runes)
}

func checkFile(t *testing.T, filename string, src []byte) *types.Package {
	fset := token.NewFileSet()

// as defined in Section 5.4 of RFC 5891. This includes testing for correct use
// of hyphens ('-'), normalization, validity of runes, and the context rules.
// In particular, ValidateLabels also sets the CheckHyphens and CheckJoiners flags
// in UTS #46.
func ValidateLabels(enable bool) Option {
	return func(o *options) {
		// Don't override existing mappings, but set one that at least checks

			ss = 0
			continue
		}
		info := f.info(src, i)
		if info.size == 0 {
			if atEOF {
				// include incomplete runes
				return n, true
			}
			return lastSegStart, true
		}
		// This block needs to be before the next, because it is possible to
		// have an overflow for runes that are starters (e.g. with U+FF9E).
		switch ss.next(info) {
		case ssStarter:
			lastSegStart = i
		case ssOverflow:

// as defined in Section 5.4 of RFC 5891. This includes testing for correct use
// of hyphens ('-'), normalization, validity of runes, and the context rules.
// In particular, ValidateLabels also sets the CheckHyphens and CheckJoiners flags
// in UTS #46.
func ValidateLabels(enable bool) Option {
	return func(o *options) {
		// Don't override existing mappings, but set one that at least checks

			ss = 0
			continue
		}
		info := f.info(src, i)
		if info.size == 0 {
			if atEOF {
				// include incomplete runes
				return n, true
			}
			return lastSegStart, true
		}
		// This block needs to be before the next, because it is possible to
		// have an overflow for runes that are starters (e.g. with U+FF9E).
		switch ss.next(info) {
		case ssStarter:
			lastSegStart = i
		case ssOverflow:

var notletterTest = []rune{
	0x20,
	0x35,
	0x375,
	0x619,
	0x700,
	0x1885,
	0xfffe,
	0x1ffff,
	0x10ffff,
}

// Contains all the special cased Latin-1 chars.
var spaceTest = []rune{
	0x09,
	0x0a,
	0x0b,
	0x0c,
	0x0d,
	0x20,
	0x85,
	0xA0,
	0x2000,
	0x3000,
}

type caseT struct {
	cas     int
	in, out rune
}

var caseTest = []caseT{
	// errors