code: def test_asof_periodindex_mismatched_freq(self):
      N = 50
      rng = period_range("1/1/1990", periods=N, freq="h")
      df = DataFrame(
          np.random.default_rng(2).standard_normal(N), index=rng
      )
  
      # Mismatched freq
      msg = "Input has different freq"
      with pytest.raises(IncompatibleFrequency, match=msg):
          df.asof(rng.asfreq("D"))
  
file_path: pandas/pandas/tests/frame/methods/test_asof.py
imports: import numpy
  import pytest
  from pandas._libs.tslibs import IncompatibleFrequency
  from pandas import DataFrame, Period, Series, Timestamp, date_range, period_range, to_datetime
  import pandas._testing
label_desc: Use image node_id 8 for calling the TestFrameAsof obj's underlying member method code with example usage: obj.test_asof_periodindex_mismatched_freq() without return types