// it resumes reading the next one down.
type Stack struct {
	tr []TokenReader
}

// Push adds tr to the top (end) of the input stack. (Popping happens automatically.)
func (s *Stack) Push(tr TokenReader) {
	s.tr = append(s.tr, tr)
}

func (s *Stack) Next() ScanToken {
	tos := s.tr[len(s.tr)-1]
	tok := tos.Next()
	for tok == scanner.EOF && len(s.tr) > 1 {
		tos.Close()

			b.uint32(uint32max) // uncompressed size

			// append a zip64 extra block to Extra
			var buf [28]byte // 2x uint16 + 3x uint64
			eb := writeBuf(buf[:])
			eb.uint16(zip64ExtraID)
			eb.uint16(24) // size = 3x uint64
			eb.uint64(h.UncompressedSize64)
			eb.uint64(h.CompressedSize64)
			eb.uint64(h.offset)
			h.Extra = append(h.Extra, buf[:]...)
		} else {
			b.uint32(h.CompressedSize)

				return 0, err
			}

			// Copy .go files from the package.
			goFiles, err := filepath.Glob("*.go")
			if err != nil {
				return 0, err
			}
			if len(goFiles) > 0 {
				args := append(append([]string{"push"}, goFiles...), deviceCwd)
				if err := adb(args...); err != nil {
					return 0, err
				}
			}
		}
	}

	deviceBin := fmt.Sprintf("%s/%s", deviceGotmp, binName)

		if strings.HasPrefix(e, "TMPDIR=") || strings.HasPrefix(e, "HOME=") || strings.HasPrefix(e, "GOCACHE=") {
			continue
		}
		env = append(env, e)
	}
	lldb := exec.Command(
		"python",
		"-", // Read script from stdin.
		target,
		appdir,
		deviceapp,
	)
	lldb.Args = append(lldb.Args, args...)
	lldb.Env = env
	lldb.Stdin = strings.NewReader(lldbDriver)
	lldb.Stdout = os.Stdout
	var out bytes.Buffer

	if b.err != nil {
		return 0, b.err
	}
	n := b.Available()
	if n < utf8.UTFMax {
		if b.Flush(); b.err != nil {
			return 0, b.err
		}
		n = b.Available()
		if n < utf8.UTFMax {
			// Can only happen if buffer is silly small.
			return b.WriteString(string(r))
		}
	}
	size = utf8.EncodeRune(b.buf[b.n:], r)
	b.n += size
	return size, nil
}

// WriteString writes a string.

	}
}

func TestCompareBytes(t *testing.T) {
	lengths := make([]int, 0) // lengths to test in ascending order
	for i := 0; i <= 128; i++ {
		lengths = append(lengths, i)
	}
	lengths = append(lengths, 256, 512, 1024, 1333, 4095, 4096, 4097)

	if !testing.Short() {
		lengths = append(lengths, 65535, 65536, 65537, 99999)
	}

	n := lengths[len(lengths)-1]
	a := make([]byte, n+1)
	b := make([]byte, n+1)
	for _, len := range lengths {

}

func (s *Slice) File() string {
	return s.base.Filename()
}

func (s *Slice) Base() *src.PosBase {
	return s.base
}

func (s *Slice) SetBase(base *src.PosBase) {
	// Cannot happen because we only have slices of already-scanned text,
	// but be prepared.
	s.base = base
}

func (s *Slice) Line() int {
	return s.line
}

func (s *Slice) Col() int {

// the given context.
func listEnv(c *build.Context) []string {
	if c == nil {
		return os.Environ()
	}

	environ := append(os.Environ(),
		"GOOS="+c.GOOS,
		"GOARCH="+c.GOARCH)
	if c.CgoEnabled {
		environ = append(environ, "CGO_ENABLED=1")
	} else {
		environ = append(environ, "CGO_ENABLED=0")
	}
	return environ
}

type apiPackage struct {
	*types.Package
	Files []*ast.File
}

			if (len(sparseMap)%2 == 0 && key != paxGNUSparseOffset) ||
				(len(sparseMap)%2 == 1 && key != paxGNUSparseNumBytes) ||
				strings.Contains(value, ",") {
				return nil, ErrHeader
			}
			sparseMap = append(sparseMap, value)
		default:
			paxHdrs[key] = value
		}
	}
	if len(sparseMap) > 0 {
		paxHdrs[paxGNUSparseMap] = strings.Join(sparseMap, ",")
	}
	return paxHdrs, nil
}

	for len(sa) > 0 && len(sb) > 0 {
		if sa[0] == sb[0] {
			ss = append(ss, identity+sa[0])
		} else {
			ss = append(ss, uniqueA+sa[0])
			ss = append(ss, uniqueB+sb[0])
		}
		sa, sb = sa[1:], sb[1:]
	}
	for len(sa) > 0 {
		ss = append(ss, uniqueA+sa[0])
		sa = sa[1:]
	}
	for len(sb) > 0 {
		ss = append(ss, uniqueB+sb[0])
		sb = sb[1:]
	}
	return strings.Join(ss, "\n")
}