TST: DataFrame.to_parquet accepts pathlib.Path with partition_cols defined (#36491)

Author: arw2019

pandas/tests/io/test_parquet.py

@@ -3,6 +3,7 @@
 from distutils.version import LooseVersion
 from io import BytesIO
 import os
+import pathlib
 from warnings import catch_warnings
 
 import numpy as np
@@ -663,6 +664,20 @@ def test_partition_cols_string(self, pa, df_full):
             assert len(dataset.partitions.partition_names) == 1
             assert dataset.partitions.partition_names == set(partition_cols_list)
 
+    @pytest.mark.parametrize(
+        "path_type", [lambda path: path, lambda path: pathlib.Path(path)]
+    )
+    def test_partition_cols_pathlib(self, pa, df_compat, path_type):
+        # GH 35902
+
+        partition_cols = "B"
+        partition_cols_list = [partition_cols]
+        df = df_compat
+
+        with tm.ensure_clean_dir() as path_str:
+            path = path_type(path_str)
+            df.to_parquet(path, partition_cols=partition_cols_list)
+
     def test_empty_dataframe(self, pa):
         # GH #27339
         df = pd.DataFrame()