{"☺☻☹", "日a本b語ç", "27 ☺☻☹=日a本b語ç\n", true},
		{"xhello", "\x00world", "17 xhello=\x00world\n", true},
		{"path", "null\x00", "", false},
		{"null\x00", "value", "", false},
		{paxSchilyXattr + "key", "null\x00", "26 SCHILY.xattr.key=null\x00\n", true},
	}

	for _, v := range vectors {
		got, err := formatPAXRecord(v.inKey, v.inVal)
		ok := (err == nil)

			if err.Error() != wantError {
				t.Fatalf("recovered panic: got %v, want %v", err.Error(), wantError)
			}
		default:
			t.Fatalf("unexpected panic value: %#v", err)
		}
	}()

	b.ReadFrom(new(negativeReader))
}

func TestWriteTo(t *testing.T) {
	var buf Buffer
	for i := 3; i < 30; i += 3 {

int returnAfterGrow(void);
int returnAfterGrowFromGo(void);
void callGoWithString(void);
*/
import "C"

import (
	"path"
	"runtime"
	"strings"
	"sync"
	"testing"
	"unsafe"
)

// Pass a func value from nestedCall to goCallback using an integer token.
var callbackMutex sync.Mutex
var callbackToken int
var callbackFuncs = make(map[int]func())

// nestedCall calls into C, back into Go, and finally to f.

pkg encoding/json, type UnmarshalTypeError struct, Struct string
pkg expvar, func Handler() http.Handler
pkg expvar, method (*Float) Value() float64
pkg expvar, method (Func) Value() interface{}
pkg expvar, method (*Int) Value() int64
pkg expvar, method (*String) Value() string
pkg go/doc, func IsPredeclared(string) bool
pkg go/types, func Default(Type) Type
pkg go/types, func IdenticalIgnoreTags(Type, Type) bool

func checkGCCBaseCmd() ([]string, error) {
	// Use $CC if set, since that's what the build uses.
	value := os.Getenv("CC")
	if value == "" {
		// Try $GCC if set, since that's what we used to use.
		value = os.Getenv("GCC")
	}
	if value == "" {
		value = defaultCC(goos, goarch)
	}
	args, err := quoted.Split(value)
	if err != nil {
		return nil, err
	}
	if len(args) == 0 {

// allowedFormats determines which formats can be used.
// The value returned is the logical OR of multiple possible formats.
// If the value is FormatUnknown, then the input Header cannot be encoded
// and an error is returned explaining why.
//
// As a by-product of checking the fields, this function returns paxHdrs, which
// contain all fields that could not be directly encoded.

		size = len(record)
		record = strconv.Itoa(size) + " " + k + "=" + v + "\n"
	}
	return record, nil
}

// validPAXRecord reports whether the key-value pair is valid where each
// record is formatted as:
//
//	"%d %s=%s\n" % (size, key, value)
//
// Keys and values should be UTF-8, but the number of bad writers out there
// forces us to be a more liberal.

pkg go/build, const IgnoreVendor ImportMode
pkg go/build, type Package struct, InvalidGoFiles []string
pkg go/constant, func ToComplex(Value) Value
pkg go/constant, func ToFloat(Value) Value
pkg go/constant, func ToInt(Value) Value
pkg go/constant, type Value interface, ExactString() string
pkg go/types, method (*Package) SetName(string)
pkg go/types, type ImportMode int

	{"3/0", "division by zero"},
	{"(1<<63)/0", "divide of value with high bit set"},
	{"3%0", "modulo by zero"},
	{"(1<<63)%0", "modulo of value with high bit set"},
	{"3<<-4", "negative left shift count"},
	{"3<<(1<<63)", "negative left shift count"},
	{"3>>-4", "negative right shift count"},
	{"3>>(1<<63)", "negative right shift count"},
	{"(1<<63)>>2", "right shift of value with high bit set"},
	{"(1<<62)>>2", ""},

	"unicode/utf8"
)

// smallBufferSize is an initial allocation minimal capacity.
const smallBufferSize = 64

// A Buffer is a variable-sized buffer of bytes with [Buffer.Read] and [Buffer.Write] methods.
// The zero value for Buffer is an empty buffer ready to use.
type Buffer struct {
	buf      []byte // contents are the bytes buf[off : len(buf)]
	off      int    // read at &buf[off], write at &buf[len(buf)]