code: def test_copy_buffer_if_needed(mock_bitpacked, mock_normal):
      # Test that type-based buffer copy dispatch works as expected.
      bytes_ = b"abcd"
      buf = pa.py_buffer(bytes_)
      offset = 1
      length = 2
  
      # Normal (non-boolean) buffer copy path.
      type_ = pa.int32()
      _copy_buffer_if_needed(buf, type_, offset, length)
      expected_byte_width = 4
      mock_normal.assert_called_once_with(
          buf, expected_byte_width, offset, length
      )
      mock_normal.reset_mock()
  
      type_ = pa.int64()
      _copy_buffer_if_needed(buf, type_, offset, length)
      expected_byte_width = 8
      mock_normal.assert_called_once_with(
          buf, expected_byte_width, offset, length
      )
      mock_normal.reset_mock()
  
      # Boolean buffer copy path.
      type_ = pa.bool_()
      _copy_buffer_if_needed(buf, type_, offset, length)
      mock_bitpacked.assert_called_once_with(buf, offset, length)
      mock_bitpacked.reset_mock()
  
imports: import logging
  import os
  import sys
  from unittest import mock
  import numpy
  import pyarrow
  import pyarrow.parquet
  import pytest
  from packaging.version import parse
  from pytest_lazyfixture import lazy_fixture
  import ray
  import ray.cloudpickle
  from ray._private.arrow_serialization import _align_bit_offset, _bytes_for_bits, _copy_bitpacked_buffer_if_needed, _copy_buffer_if_needed, _copy_normal_buffer_if_needed, _copy_offsets_buffer_if_needed
  from ray._private.utils import _get_pyarrow_version
  from ray.data.extensions.tensor_extension import ArrowTensorArray, ArrowVariableShapedTensorArray
  from ray.tests.conftest import *
label_desc: Use image node_id 4 for calling a global function with example usage: test_copy_buffer_if_needed(mock_bitpacked, mock_normal) without return types