code: def test_row_count_empty_file(tmp_path: Path) -> None:
      tmp_path.mkdir(exist_ok=True)
      file_path = tmp_path / "test.parquet"
      df = pl.DataFrame({"a": []}, schema={"a": pl.Float32})
      df.write_parquet(file_path)
      result = (
          pl.scan_parquet(file_path).with_row_count("idx").collect()
      )
      assert result.schema == OrderedDict(
          [("idx", pl.UInt32), ("a", pl.Float32)]
      )
  
imports: from __future__ import annotations
  from collections import OrderedDict
  from pathlib import Path
  from typing import TYPE_CHECKING, Any
  import pandas
  import pytest
  import polars
  from polars.testing import assert_frame_equal
label_desc: Use image node_id 20 for calling a global function with example usage: test_row_count_empty_file(tmp_path) without return types