if err := r.UnreadByte(); err == nil {
			t.Errorf("n = %d: expected error on UnreadByte", n)
		}
	}
}

func TestUnreadByteOthers(t *testing.T) {
	// A list of readers to use in conjunction with UnreadByte.
	var readers = []func(*Reader, byte) ([]byte, error){
		(*Reader).ReadBytes,
		(*Reader).ReadSlice,
		func(r *Reader, delim byte) ([]byte, error) {
			data, err := r.ReadString(delim)

			panic(err)
		}
		b, err = io.ReadAll(f)
		if err != nil {
			panic(err)
		}
	}
	return bytes.NewReader(b), int64(len(b))
}

func TestIssue8186(t *testing.T) {
	// Directory headers & data found in the TOC of a JAR file.
	dirEnts := []string{

			for i, hdr := range hdrs {
				if i >= len(v.headers) {
					t.Fatalf("entry %d: unexpected header:\ngot %+v", i, *hdr)
				}
				if !reflect.DeepEqual(*hdr, *v.headers[i]) {
					t.Fatalf("entry %d: incorrect header:\ngot  %+v\nwant %+v", i, *hdr, *v.headers[i])
				}
			}
			if len(hdrs) != len(v.headers) {
				t.Fatalf("got %d headers, want %d headers", len(hdrs), len(v.headers))
			}

			for i, sum := range chksums {

	TypeXHeader = 'x'

	// Type 'g' is used by the PAX format to store key-value records that
	// are relevant to all subsequent files.
	// This package only supports parsing and composing such headers,
	// but does not currently support persisting the global state across files.
	TypeXGlobalHeader = 'g'

	// Type 'S' indicates a sparse file in the GNU format.
	TypeGNUSparse = 'S'

			// Otherwise one bad and unneeded field in an otherwise okay struct
			// makes the whole program not compile. Much of the time these
			// structs are in system headers that cannot be corrected.
			continue
		}

		// Round off up to talign, assumed to be a power of 2.
		off = (off + talign - 1) &^ (talign - 1)

		if f.ByteOffset > off {

pkg encoding/pem, func EncodeToMemory(*Block) []uint8
pkg encoding/pem, type Block struct
pkg encoding/pem, type Block struct, Bytes []uint8
pkg encoding/pem, type Block struct, Headers map[string]string
pkg encoding/pem, type Block struct, Type string
pkg encoding/xml, const Header ideal-string
pkg encoding/xml, func CopyToken(Token) Token
pkg encoding/xml, func Escape(io.Writer, []uint8)

	// The format of the original Unix V7 tar tool prior to standardization.
	formatV7

	// FormatUSTAR represents the USTAR header format defined in POSIX.1-1988.
	//
	// While this format is compatible with most tar readers,
	// the format has several limitations making it unsuitable for some usages.
	// Most notably, it cannot support sparse files, files larger than 8GiB,
	// filenames larger than 256 characters, and non-ASCII filenames.
	//

	Comment string

	// NonUTF8 indicates that Name and Comment are not encoded in UTF-8.
	//
	// By specification, the only other encoding permitted should be CP-437,
	// but historically many ZIP readers interpret Name and Comment as whatever
	// the system's local character encoding happens to be.
	//
	// This flag should only be set if the user intends to encode a non-portable

template literal, controlled by the
[`jstmpllitinterp` setting](/pkg/html/template#hdr-Security_Model).
This behavior was backported to Go 1.19.8+ and Go 1.20.3+.

Go 1.21 introduced a limit on the maximum number of MIME headers and multipart
forms, controlled by the
[`multipartmaxheaders` and `multipartmaxparts` settings](/pkg/mime/multipart#hdr-Limits)
respectively.
This behavior was backported to Go 1.19.8+ and Go 1.20.3+.

		return err
	}
	buf := bufio.NewReader(rs)

	// The count of files inside a zip is truncated to fit in a uint16.
	// Gloss over this by reading headers until we encounter
	// a bad one, and then only report an ErrFormat or UnexpectedEOF if
	// the file count modulo 65536 is incorrect.
	for {
		f := &File{zip: r, zipr: rdr}
		err = readDirectoryHeader(f, buf)