// another n bytes. After Grow(n), at least n bytes can be written to the
// buffer without another allocation.
// If n is negative, Grow will panic.
// If the buffer can't grow it will panic with [ErrTooLarge].
func (b *Buffer) Grow(n int) {
	if n < 0 {
		panic("bytes.Buffer.Grow: negative count")
	}
	m := b.grow(n)
	b.buf = b.buf[:m]
}

// Write appends the contents of p to the buffer, growing the buffer as

// byte arrays sized based on width.
func NewBytePoolCap(maxSize uint64, width int, capwidth int) (bp *BytePoolCap) {
	if capwidth <= 0 {
		panic("total buffer capacity must be provided")
	}
	if capwidth < 64 {
		panic("buffer capped with smaller than 64 bytes is not supported")
	}
	if width > capwidth {
		panic("minimum buffer length cannot be > capacity of the buffer")
	}
	return &BytePoolCap{
		c:    make(chan []byte, maxSize),

const (
	policyCondEqual         = "eq"
	policyCondStartsWith    = "starts-with"
	policyCondContentLength = "content-length-range"
)

// toString - Safely convert interface to string without causing panic.
func toString(val interface{}) string {
	switch v := val.(type) {
	case string:
		return v
	default:
		return ""
	}
}

// toLowerString - safely convert interface to lower string

// as we only guarantee a lookback buffer size of one, any subsequent calls to back()
// before calling next() may panic
func (s *scanner) back() {
	if s.ipos <= 0 {
		panic("back buffer exhausted")
	}
	s.ipos--
	s.pos--

The [GODEBUG History](#history) gives the exact defaults for each Go toolchain version.
For example, Go 1.21 introduces the `panicnil` setting,
controlling whether `panic(nil)` is allowed;
it defaults to `panicnil=0`, making `panic(nil)` a run-time error.
Using `panicnil=1` restores the behavior of Go 1.20 and earlier.

When compiling a work module or workspace that declares

	}
}

type panicReader struct{ panic bool }

func (r panicReader) Read(p []byte) (int, error) {
	if r.panic {
		panic("oops")
	}
	return 0, io.EOF
}

// Make sure that an empty Buffer remains empty when
// it is "grown" before a Read that panics
func TestReadFromPanicReader(t *testing.T) {

	// First verify non-panic behaviour
	var buf Buffer

At that point, the program is terminated and the error
condition is reported, including the value of the argument to <code>panic</code>.
This termination sequence is called <i>panicking</i>.
</p>

<pre>
panic(42)
panic("unreachable")
panic(Error("cannot parse"))
</pre>

<p>
The <code>recover</code> function allows a program to manage behavior
of a panicking goroutine.

			if err := tx.First(&User{}, "name = ?", user.Name).Error; err != nil {
				t.Fatalf("Should find saved record")
			}

			panic("force panic")
		})
	})

	if err := DB.First(&User{}, "name = ?", "transaction-block-3").Error; err == nil {
		t.Fatalf("Should not find record after panic rollback")
	}
}

func TestTransactionRaiseErrorOnRollbackAfterCommit(t *testing.T) {
	tx := DB.Begin()

func TestNegativeRead(t *testing.T) {
	// should panic with a description pointing at the reader, not at itself.
	// (should NOT panic with slice index error, for example.)
	b := NewReader(new(negativeReader))
	defer func() {
		switch err := recover().(type) {
		case nil:
			t.Fatal("read did not panic")
		case error:

	br := bufio.NewReader(bytes.NewReader(b))
loop:
	for {
		_, err := br.ReadByte()
		switch err {
		case nil:
			continue loop
		case io.EOF:
			break loop
		default:
			panic(err)
		}
	}
}

func BenchmarkScanner(b *testing.B) {
	b.Run("small", func(b *testing.B) {
		for i := 0; i < b.N; i++ {
			benchmarkScanner(smallInput)
		}
	})