ENH: add __fspath__ to pandas own file-like objects

- HDFStore
- ExcelFile

Author: TomAugspurger

doc/source/whatsnew/v0.21.0.txt

@@ -21,7 +21,7 @@ New features
 ~~~~~~~~~~~~
 
 - Support for `PEP 519 -- Adding a file system path protocol <https://www.python.org/dev/peps/pep-0519/>`_ on most readers and writers (:issue:`13823`)
-
+- Added `__fspath__` method to :class`:pandas.HDFStore` and :class:`pandas.ExcelFile` to work properly with th file system path protocol (:issue:`13823`)
 
 
 .. _whatsnew_0210.enhancements.other:

pandas/io/excel.py

@@ -263,6 +263,9 @@ def __init__(self, io, **kwds):
             raise ValueError('Must explicitly set engine if not passing in'
                              ' buffer or path for io.')
 
+    def __fspath__(self):
+        return self._io
+
     def parse(self, sheetname=0, header=0, skiprows=None, skip_footer=0,
               names=None, index_col=None, parse_cols=None, parse_dates=False,
               date_parser=None, na_values=None, thousands=None,

pandas/io/pytables.py

@@ -440,7 +440,7 @@ def __init__(self, path, mode=None, complevel=None, complib=None,
                 "complib only supports {libs} compression.".format(
                     libs=tables.filters.all_complibs))
 
-        self._path = path
+        self._path = _stringify_path(path)
         if mode is None:
             mode = 'a'
         self._mode = mode
@@ -451,6 +451,9 @@ def __init__(self, path, mode=None, complevel=None, complib=None,
         self._filters = None
         self.open(mode=mode, **kwargs)
 
+    def __fspath__(self):
+        return self._path
+
     @property
     def root(self):
         """ return the root node """

pandas/tests/io/test_excel.py

@@ -2499,3 +2499,13 @@ def custom_converter(css):
             n_cells += 1
 
     assert n_cells == (10 + 1) * (3 + 1)
+
+
+@pytest.mark.skipif(sys.version_info < (3, 6), reason='requires fspath')
+def test_excelfile_fspath():
+    with tm.ensure_clean('foo.xlsx') as path:
+        df = DataFrame({"A": [1, 2]})
+        df.to_excel(path)
+        xl = ExcelFile(path)
+        result = os.fspath(xl)
+        assert result == path

pandas/tests/io/test_pytables.py

@@ -5154,6 +5154,13 @@ def test_query_compare_column_type(self):
                         expected = df.loc[[], :]
                     tm.assert_frame_equal(expected, result)
 
+    @pytest.mark.skipif(sys.version_info < (3, 6),
+                        reason="requires fspath")
+    def test_hdfstore_fspath(self):
+        with tm.ensure_clean('foo.h5') as path:
+            with pd.HDFStore(path) as store:
+                assert os.fspath(store) == path
+
 
 class TestHDFComplexValues(Base):
     # GH10447