func stack28()   { var buf [28]byte; use(buf[:]); C.callGoStackCheck() }
func stack32()   { var buf [32]byte; use(buf[:]); C.callGoStackCheck() }
func stack36()   { var buf [36]byte; use(buf[:]); C.callGoStackCheck() }
func stack40()   { var buf [40]byte; use(buf[:]); C.callGoStackCheck() }
func stack44()   { var buf [44]byte; use(buf[:]); C.callGoStackCheck() }

}

// Verify that contents of buf match the string s.
func check(t *testing.T, testname string, buf *Buffer, s string) {
	bytes := buf.Bytes()
	str := buf.String()
	if buf.Len() != len(bytes) {
		t.Errorf("%s: buf.Len() == %d, len(buf.Bytes()) == %d", testname, buf.Len(), len(bytes))
	}

	if buf.Len() != len(str) {
		t.Errorf("%s: buf.Len() == %d, len(buf.String()) == %d", testname, buf.Len(), len(str))
	}

			// and that the data is correct.

			w.Reset()
			buf := NewWriterSize(w, bs)
			context := fmt.Sprintf("nwrite=%d bufsize=%d", nwrite, bs)
			n, e1 := buf.Write(data[0:nwrite])
			if e1 != nil || n != nwrite {
				t.Errorf("%s: buf.Write %d = %d, %v", context, nwrite, n, e1)
				continue
			}
			if e := buf.Flush(); e != nil {
				t.Errorf("%s: buf.Flush = %v", context, e)
			}

			written := w.Bytes()

	parser := newParser("amd64")
	var buf strings.Builder
	parser.errorWriter = &buf

	for _, cat := range testcats {
		for _, test := range cat.tests {
			parser.allowABI = cat.allowABI
			parser.errorCount = 0
			parser.lineNum++
			if !parser.pseudo(test.pseudo, tokenize(test.operands)) {
				t.Fatalf("Wrong pseudo-instruction: %s", test.pseudo)
			}
			errorLine := buf.String()
			if test.expected != errorLine {

)

var IsSpace = isSpace

const DefaultBufSize = defaultBufSize

func (s *Scanner) MaxTokenSize(n int) {
	if n < utf8.UTFMax || n > 1e9 {
		panic("bad max token size")
	}
	if n < len(s.buf) {
		s.buf = make([]byte, n)
	}
	s.maxTokenSize = n
}

// ErrOrEOF is like Err, but returns EOF. Used to test a corner case.
func (s *Scanner) ErrOrEOF() error {
	return s.err

	for n := attempts; n > 0; n-- {
		cmd := exec.Command(os.Args[0], args...)
		cmd.Env = append(os.Environ(), "test18146=exec")
		buf := bytes.NewBuffer(nil)
		cmd.Stdout = buf
		cmd.Stderr = buf
		if err := cmd.Start(); err != nil {
			// We are starting so many processes that on
			// some systems (problem seen on Darwin,
			// Dragonfly, OpenBSD) the fork call will fail

			writeSync(fd, buf) {
				outputBuf += decoder.decode(buf);
				const nl = outputBuf.lastIndexOf("\n");
				if (nl != -1) {
					console.log(outputBuf.substring(0, nl));
					outputBuf = outputBuf.substring(nl + 1);
				}
				return buf.length;
			},
			write(fd, buf, offset, length, position, callback) {
				if (offset !== 0 || length !== buf.length || position !== null) {
					callback(enosys());

func (ss *suffixSaver) Suffix() []byte {
	if len(ss.buf) < ss.keep {
		return ss.buf
	}
	buf := make([]byte, ss.keep)
	n := copy(buf, ss.buf[ss.start:])
	copy(buf[n:], ss.buf[:])
	return buf
}

func (ss *suffixSaver) Write(p []byte) (n int, err error) {
	n = len(p)
	ss.size += int64(len(p))
	if len(ss.buf) < ss.keep {
		space := ss.keep - len(ss.buf)
		add := len(p)
		if add > space {
			add = space

			ok:  false,
			out: "+pkg syscall, type RawSockaddrInet6 struct\n",
		},
	}
	for _, tt := range tests {
		buf := new(strings.Builder)
		gotOK := compareAPI(buf, tt.features, tt.required, tt.exception)
		if gotOK != tt.ok {
			t.Errorf("%s: ok = %v; want %v", tt.name, gotOK, tt.ok)
		}
		if got := buf.String(); got != tt.out {
			t.Errorf("%s: output differs\nGOT:\n%s\nWANT:\n%s", tt.name, got, tt.out)
		}
	}
}

		}
	}
}

func TestReaderDoubleUnreadRune(t *testing.T) {
	buf := NewBuffer([]byte("groucho"))
	if _, _, err := buf.ReadRune(); err != nil {
		// should not happen
		t.Fatal(err)
	}
	if err := buf.UnreadByte(); err != nil {
		// should not happen
		t.Fatal(err)
	}
	if err := buf.UnreadByte(); err == nil {
		t.Fatal("UnreadByte: expected error, got nil")
	}
}