func()

in insertablebuffer.go [84:111]

• 22 lines of code
• 7 McCabe index (conditional complexity)

func (b *Builder) grow(n int) int {
	m := b.Len()
	// If buffer is empty, reset to recover space.
	if m == 0 && b.off != 0 {
		b.Truncate(0)
	}
	if len(b.buf)+n > cap(b.buf) {
		var buf []byte
		if b.buf == nil && n <= len(b.bootstrap) {
			buf = b.bootstrap[0:]
		} else if m+n <= cap(b.buf)/2 {
			// We can slide things down instead of allocating a new
			// slice. We only need m+n <= cap(b.buf) to slide, but
			// we instead let capacity get twice as large so we
			// don't spend all our time copying.
			copy(b.buf[:], b.buf[b.off:])
			buf = b.buf[:m]
		} else {
			// not enough space anywhere
			buf = makeSlice(2*cap(b.buf) + n)
			copy(buf, b.buf[b.off:])
		}
		b.buf = buf
		b.off = 0
	}
	b.buf = b.buf[0 : b.off+m+n]
	return b.off + m
}