doBench(b, func(b *testing.B, buf0 []byte, level, n int) {
		b.ReportAllocs()
		b.StopTimer()
		b.SetBytes(int64(n))

		compressed := new(bytes.Buffer)
		w, err := NewWriter(compressed, level)
		if err != nil {
			b.Fatal(err)
		}
		for i := 0; i < n; i += len(buf0) {
			if len(buf0) > n-i {
				buf0 = buf0[:n-i]
			}
			io.Copy(w, bytes.NewReader(buf0))
		}
		w.Close()
		buf1 := compressed.Bytes()

// The noescape comment only applies to the next func,
// which must not have a body.

//go:noescape

func F1([]byte)

func F2([]byte)

func G() {
	var buf1 [10]byte
	F1(buf1[:])

	var buf2 [10]byte // ERROR "moved to heap: buf2"
	F2(buf2[:])

	"runtime"
	"testing"
)

func BenchmarkEncode(b *testing.B) {
	doBench(b, func(b *testing.B, buf0 []byte, level, n int) {
		b.StopTimer()
		b.SetBytes(int64(n))

		buf1 := make([]byte, n)
		for i := 0; i < n; i += len(buf0) {
			if len(buf0) > n-i {
				buf0 = buf0[:n-i]
			}
			copy(buf1[i:], buf0)
		}
		buf0 = nil
		w, err := NewWriter(io.Discard, level)
		if err != nil {
			b.Fatal(err)
		}

}

func BenchmarkEncoder(b *testing.B) {
	buf, err := os.ReadFile("../testdata/e.txt")
	if err != nil {
		b.Fatal(err)
	}
	if len(buf) == 0 {
		b.Fatalf("test file has no data")
	}

	for e := 4; e <= 6; e++ {
		n := int(math.Pow10(e))
		buf0 := buf
		buf1 := make([]byte, n)
		for i := 0; i < n; i += len(buf0) {
			if len(buf0) > n-i {
				buf0 = buf0[:n-i]
			}
			copy(buf1[i:], buf0)
		}

	}
	for i, c := range runes {
		buf := make([]byte, 3)
		size := utf8.EncodeRune(buf, c)
		fmt.Printf("%d: %d %[2]s %d\n", i, buf, size)
	}
	// Output:
	// 0: [239 191 189] � 3
	// 1: [239 191 189] � 3
	// 2: [239 191 189] � 3
}

func ExampleFullRune() {
	buf := []byte{228, 184, 150} // 世
	fmt.Println(utf8.FullRune(buf))
	fmt.Println(utf8.FullRune(buf[:2]))
	// Output:
	// true
	// false

	// read
}

func ExampleMultiWriter() {
	r := strings.NewReader("some io.Reader stream to be read\n")

	var buf1, buf2 strings.Builder
	w := io.MultiWriter(&buf1, &buf2)

	if _, err := io.Copy(w, r); err != nil {
		log.Fatal(err)
	}

	fmt.Print(buf1.String())
	fmt.Print(buf2.String())

	// Output:
	// some io.Reader stream to be read
	// some io.Reader stream to be read
}

		panic("crypto/ecdh: internal error: isLess input too large")
	}
	bufA, bufB := make([]byte, 72), make([]byte, 72)
	for i := range a {
		bufA[i], bufB[i] = a[len(a)-i-1], b[len(b)-i-1]
	}

	// Perform a subtraction with borrow.
	var borrow uint64
	for i := 0; i < len(bufA); i += 8 {
		limbA, limbB := byteorder.LeUint64(bufA[i:]), byteorder.LeUint64(bufB[i:])
		_, borrow = bits.Sub64(limbA, limbB, borrow)
	}

			bufrw.Write([]byte("[hijack-to-bufw]"))
			bufrw.Flush()
			conn.Write([]byte("[hijack-to-conn]"))
			conn.Close()
			wrotec <- true
		}()
	})
	ln := &oneConnListener{conn: conn}
	go Serve(ln, handler)
	<-conn.closec
	<-wrotec
	if g, w := buf.String(), "[hijack-to-bufw][hijack-to-conn]"; g != w {
		t.Errorf("wrote %q; want %q", g, w)
	}
}

func TestDoubleHijack(t *testing.T) {

	func() {
		buf1 := bytes.NewReader([]byte("foo"))
		buf2 := bytes.NewReader([]byte("bar"))
		mr = MultiReader(buf1, buf2)
		runtime.SetFinalizer(buf1, func(*bytes.Reader) {
			close(closed)
		})
	}()

	buf := make([]byte, 4)
	if n, err := ReadFull(mr, buf); err != nil || string(buf) != "foob" {
		t.Fatalf(`ReadFull = %d (%q), %v; want 3, "foo", nil`, n, buf[:n], err)
	}

	runtime.GC()

}

func verifyPrint(t *testing.T, filename string, ast1 *File) {
	var buf1 bytes.Buffer
	_, err := Fprint(&buf1, ast1, LineForm)
	if err != nil {
		panic(err)
	}
	bytes1 := buf1.Bytes()

	ast2, err := Parse(NewFileBase(filename), &buf1, nil, nil, 0)
	if err != nil {
		panic(err)
	}

	var buf2 bytes.Buffer
	_, err = Fprint(&buf2, ast2, LineForm)
	if err != nil {
		panic(err)
	}