code: def test_fillna_float_casting(
      self, dtype, any_real_numpy_dtype, scalar
  ):
      # GH-43424
      ser = Series([np.nan, 1.2], dtype=dtype)
      fill_values = Series([2, 2], dtype=any_real_numpy_dtype)
      if scalar:
          fill_values = fill_values.dtype.type(2)
  
      result = ser.fillna(fill_values)
      expected = Series([2.0, 1.2], dtype=dtype)
      tm.assert_series_equal(result, expected)
  
      ser = Series([np.nan, 1.2], dtype=dtype)
      mask = ser.isna().to_numpy()
      ser[mask] = fill_values
      tm.assert_series_equal(ser, expected)
  
      ser = Series([np.nan, 1.2], dtype=dtype)
      ser.mask(mask, fill_values, inplace=True)
      tm.assert_series_equal(ser, expected)
  
      ser = Series([np.nan, 1.2], dtype=dtype)
      res = ser.where(~mask, fill_values)
      tm.assert_series_equal(res, expected)
  
imports: from datetime import datetime, timedelta, timezone
  import numpy
  import pytest
  import pytz
  from pandas import Categorical, DataFrame, DatetimeIndex, NaT, Period, Series, Timedelta, Timestamp, date_range, isna, timedelta_range
  import pandas._testing
  from pandas.core.arrays import period_array
label_desc: Use image node_id 26 for calling the TestSeriesFillNA obj's underlying member method code with example usage: obj.test_fillna_float_casting(dtype, any_real_numpy_dtype, scalar) without return types