}))
	// Output: ¡¡¡Hello, Gophers
}

func ExampleToValidUTF8() {
	fmt.Printf("%s\n", strings.ToValidUTF8("abc", "\uFFFD"))
	fmt.Printf("%s\n", strings.ToValidUTF8("a\xffb\xC0\xAFc\xff", ""))
	fmt.Printf("%s\n", strings.ToValidUTF8("\xed\xa0\x80", "abc"))
	// Output:
	// abc
	// abc
	// abc

	{"\xFC\x80\x80\x80\x80\xAF", "\uFFFD", "\uFFFD"},
}

func TestToValidUTF8(t *testing.T) {
	for _, tc := range toValidUTF8Tests {
		got := ToValidUTF8(tc.in, tc.repl)
		if got != tc.out {
			t.Errorf("ToValidUTF8(%q, %q) = %q; want %q", tc.in, tc.repl, got, tc.out)
		}
	}
}

func BenchmarkToUpper(b *testing.B) {
	for _, tc := range upperTests {
		b.Run(tc.in, func(b *testing.B) {

func ToTitleSpecial(c unicode.SpecialCase, s string) string {
	return Map(c.ToTitle, s)
}

// ToValidUTF8 returns a copy of the string s with each run of invalid UTF-8 byte sequences
// replaced by the replacement string, which may be empty.
func ToValidUTF8(s, replacement string) string {
	var b Builder

	for i, c := range s {
		if c != utf8.RuneError {
			continue
		}

	{"\xFC\x80\x80\x80\x80\xAF", "\uFFFD", "\uFFFD"},
}

func TestToValidUTF8(t *testing.T) {
	for _, tc := range toValidUTF8Tests {
		got := ToValidUTF8([]byte(tc.in), []byte(tc.repl))
		if !Equal(got, []byte(tc.out)) {
			t.Errorf("ToValidUTF8(%q, %q) = %q; want %q", tc.in, tc.repl, got, tc.out)
		}
	}
}

func TestTrimSpace(t *testing.T) { runStringTests(t, TrimSpace, "TrimSpace", trimSpaceTests) }

pkg bytes, func ToValidUTF8([]uint8, []uint8) []uint8
pkg crypto/ed25519, const PrivateKeySize = 64
pkg crypto/ed25519, const PrivateKeySize ideal-int
pkg crypto/ed25519, const PublicKeySize = 32
pkg crypto/ed25519, const PublicKeySize ideal-int
pkg crypto/ed25519, const SeedSize = 32
pkg crypto/ed25519, const SeedSize ideal-int
pkg crypto/ed25519, const SignatureSize = 64
pkg crypto/ed25519, const SignatureSize ideal-int

		{"Title", Func, 0},
		{"ToLower", Func, 0},
		{"ToLowerSpecial", Func, 0},
		{"ToTitle", Func, 0},
		{"ToTitleSpecial", Func, 0},
		{"ToUpper", Func, 0},
		{"ToUpperSpecial", Func, 0},
		{"ToValidUTF8", Func, 13},
		{"Trim", Func, 0},
		{"TrimFunc", Func, 0},
		{"TrimLeft", Func, 0},
		{"TrimLeftFunc", Func, 0},
		{"TrimPrefix", Func, 1},
		{"TrimRight", Func, 0},
		{"TrimRightFunc", Func, 0},