System.Runtime.CompilerServices.ReadOnlyCollectionBuilder.EnsureCapacity C# (CSharp) Method

        private void EnsureCapacity(int min)
        {
            if (_items.Length < min)
            {
                int newCapacity = DefaultCapacity;
                if (_items.Length > 0)
                {
                    newCapacity = _items.Length * 2;
                }
                if (newCapacity < min)
                {
                    newCapacity = min;
                }
                Capacity = newCapacity;
            }
        }