}

// Empty buf through repeated reads into fub.
// The initial contents of buf corresponds to the string s.
func empty(t *testing.T, testname string, buf *Buffer, s string, fub []byte) {
	check(t, testname+" (empty 1)", buf, s)

	for {
		n, err := buf.Read(fub)
		if n == 0 {
			break
		}
		if err != nil {
			t.Errorf(testname+" (empty 2): err should always be nil, found err == %s", err)

func (b *Buffer) String() string {
	if b == nil {
		// Special case, useful in debugging.
		return "<nil>"
	}
	return string(b.buf[b.off:])
}

// empty reports whether the unread portion of the buffer is empty.
func (b *Buffer) empty() bool { return len(b.buf) <= b.off }

// Len returns the number of bytes of the unread portion of the buffer;
// b.Len() == len(b.Bytes()).

// [Scanner] to read more data into the slice and try again with a
// longer slice starting at the same point in the input.
//
// The function is never called with an empty data slice unless atEOF
// is true. If atEOF is true, however, data may be non-empty and,
// as always, holds unprocessed text.
type SplitFunc func(data []byte, atEOF bool) (advance int, token []byte, err error)

// Errors returned by Scanner.
var (

C's union types are represented as a Go byte array with the same length.

Go structs cannot embed fields with C types.

Go code cannot refer to zero-sized fields that occur at the end of
non-empty C structs. To get the address of such a field (which is the
only operation you can do with a zero-sized field) you must take the
address of the struct and add the size of the struct.

//   - adjacent fragments are coalesced together
//   - only the last fragment may be empty
//   - the endOffset of the last fragment is the total size
func invertSparseEntries(src []sparseEntry, size int64) []sparseEntry {
	dst := src[:0]
	var pre sparseEntry
	for _, cur := range src {
		if cur.Length == 0 {
			continue // Skip empty fragments
		}
		pre.Length = cur.Offset - pre.Offset
		if pre.Length > 0 {

// A nil argument is equivalent to an empty slice.
func Equal(a, b []byte) bool {
	// Neither cmd/compile nor gccgo allocates for these string conversions.
	return string(a) == string(b)
}

// Compare returns an integer comparing two byte slices lexicographically.
// The result will be 0 if a == b, -1 if a < b, and +1 if a > b.
// A nil argument is equivalent to an empty slice.
func Compare(a, b []byte) int {

// imaginary parts.
type complex128 complex128

// string is the set of all strings of 8-bit bytes, conventionally but not
// necessarily representing UTF-8-encoded text. A string may be empty, but
// not nil. Values of string type are immutable.
type string string

// int is a signed integer type that is at least 32 bits in size. It is a
// distinct type, however, and not an alias for, say, int32.
type int int

		{data2[:1536] + trash, 1, ErrHeader},
		{data2[:2048], 1, io.EOF}, // Exactly 1 empty block
		{data2[:2048] + trash[:1], 1, io.ErrUnexpectedEOF},
		{data2[:2048] + trash[:511], 1, io.ErrUnexpectedEOF},
		{data2[:2048] + trash, 1, ErrHeader},
		{data2[:2560], 1, io.EOF}, // Exactly 2 empty blocks (normal end-of-stream)
		{data2[:2560] + trash[:1], 1, io.EOF},
		{data2[:2560] + trash[:511], 1, io.EOF},

denial of service attacks, this setting and default was backported to Go
1.19.13, Go 1.20.8, and Go 1.21.1.

Go 1.22 made it an error for a request or response read by a net/http
client or server to have an empty Content-Length header.
This behavior is controlled by the `httplaxcontentlength` setting.

Go 1.22 changed the behavior of ServeMux to accept extended
patterns and unescape both patterns and request paths by segment.

}

// Test that the line splitter handles a final empty line.
func TestScanLineEmptyFinalLine(t *testing.T) {
	const text = "abcdefghijklmn\nopqrstuvwxyz\n\n"
	lines := []string{
		"abcdefghijklmn",
		"opqrstuvwxyz",
		"",
	}
	testNoNewline(text, lines, t)
}

// Test that the line splitter handles a final empty line with a carriage return but no newline.