t.Errorf("buf = %q; want foo", buf)
	}

	r.Reset(strings.NewReader("bar bar"))
	checkAll(r, "bar bar")

	*r = Reader{} // zero out the Reader
	r.Reset(strings.NewReader("bar bar"))
	checkAll(r, "bar bar")

	// Wrap a reader and then Reset to that reader.
	r.Reset(strings.NewReader("recur"))
	r2 := NewReader(r)
	checkAll(r2, "recur")
	r.Reset(strings.NewReader("recur2"))
	r2.Reset(r)

	buf := NewBuffer(make([]byte, n))
	for i := 0; i < b.N; i++ {
		buf.Reset()
		for i := 0; i < n; i++ {
			buf.WriteByte('x')
		}
	}
}

func BenchmarkWriteRune(b *testing.B) {
	const n = 4 << 10
	const r = '☺'
	b.SetBytes(int64(n * utf8.RuneLen(r)))
	buf := NewBuffer(make([]byte, n*utf8.UTFMax))
	for i := 0; i < b.N; i++ {
		buf.Reset()
		for i := 0; i < n; i++ {
			buf.WriteRune(r)
		}
	}
}

				t.Fatalf("Wrong pseudo-instruction: %s", test.pseudo)
			}
			errorLine := buf.String()
			if test.expected != errorLine {
				t.Errorf("Unexpected error %q; expected %q", errorLine, test.expected)
			}
			buf.Reset()
		}
	}

func (b *Buffer) Truncate(n int) {
	if n == 0 {
		b.Reset()
		return
	}
	b.lastRead = opInvalid
	if n < 0 || n > b.Len() {
		panic("bytes.Buffer: truncation out of range")
	}
	b.buf = b.buf[:b.off+n]
}

// Reset resets the buffer to be empty,
// but it retains the underlying storage for use by future writes.
// Reset is the same as [Buffer.Truncate](0).
func (b *Buffer) Reset() {
	b.buf = b.buf[:0]
	b.off = 0

now unbuffered, with capacity 0.
The main effect of this change is that Go now guarantees
that for any call to a `Reset` or `Stop` method, no stale values
prepared before that call will be sent or received after the call.
Earlier versions of Go used channels with a one-element buffer,
making it difficult to use `Reset` and `Stop` correctly.
A visible effect of this change is that `len` and `cap` of timer channels

	}
	r.i += int64(m)
	n = int64(m)
	if m != len(b) && err == nil {
		err = io.ErrShortWrite
	}
	return
}

// Reset resets the [Reader.Reader] to be reading from b.
func (r *Reader) Reset(b []byte) { *r = Reader{b, 0, -1} }

// NewReader returns a new [Reader.Reader] reading from b.

type Decompressor func(r io.Reader) io.ReadCloser

var flateWriterPool sync.Pool

func newFlateWriter(w io.Writer) io.WriteCloser {
	fw, ok := flateWriterPool.Get().(*flate.Writer)
	if ok {
		fw.Reset(w)
	} else {
		fw, _ = flate.NewWriter(w, 5)
	}
	return &pooledFlateWriter{fw: fw}
}

type pooledFlateWriter struct {
	mu sync.Mutex // guards Close and Write
	fw *flate.Writer
}

			c = ' ' // Treat the checksum field itself as all spaces.
		}
		unsigned += int64(c)
		signed += int64(int8(c))
	}
	return unsigned, signed
}

// reset clears the block with all zeros.
func (b *block) reset() {
	*b = block{}
}

type headerV7 [blockSize]byte

func (h *headerV7) name() []byte     { return h[000:][:100] }
func (h *headerV7) mode() []byte     { return h[100:][:8] }

fi

echo Updated for $CODE/$DATA: $files

commitmsg="lib/time: update to $CODE/$DATA

Commit generated by update.bash.

For #22487.
"

if [ "$1" = "-commit" ]; then
	echo "Creating commit. Run 'git reset HEAD^' to undo commit."
	echo
	git commit -m "$commitmsg" $files
	echo
	git log -n1 --stat
	echo

### Go 1.23

Go 1.23 changed the channels created by package time to be unbuffered
(synchronous), which makes correct use of the [`Timer.Stop`](/pkg/time/#Timer.Stop)
and [`Timer.Reset`](/pkg/time/#Timer.Reset) method results much easier.
The [`asynctimerchan` setting](/pkg/time/#NewTimer) disables this change.
There are no runtime metrics for this change,