diff --git a/doc/source/whatsnew/v2.1.3.rst b/doc/source/whatsnew/v2.1.3.rst index 31ab01f171b4a..6413e16afd800 100644 --- a/doc/source/whatsnew/v2.1.3.rst +++ b/doc/source/whatsnew/v2.1.3.rst @@ -13,7 +13,7 @@ including other versions of pandas. Fixed regressions ~~~~~~~~~~~~~~~~~ -- +- Fixed infinite recursion from operations that return a new object on some DataFrame subclasses (:issue:`55763`) - .. --------------------------------------------------------------------------- diff --git a/pandas/core/frame.py b/pandas/core/frame.py index f37be37f37693..613b6a39841a2 100644 --- a/pandas/core/frame.py +++ b/pandas/core/frame.py @@ -648,7 +648,7 @@ def _constructor(self) -> Callable[..., DataFrame]: def _constructor_from_mgr(self, mgr, axes): if self._constructor is DataFrame: # we are pandas.DataFrame (or a subclass that doesn't override _constructor) - return self._from_mgr(mgr, axes=axes) + return DataFrame._from_mgr(mgr, axes=axes) else: assert axes is mgr.axes return self._constructor(mgr) diff --git a/pandas/core/series.py b/pandas/core/series.py index 88d3616423155..368090a37d977 100644 --- a/pandas/core/series.py +++ b/pandas/core/series.py @@ -637,7 +637,7 @@ def _constructor(self) -> Callable[..., Series]: def _constructor_from_mgr(self, mgr, axes): if self._constructor is Series: # we are pandas.Series (or a subclass that doesn't override _constructor) - ser = self._from_mgr(mgr, axes=axes) + ser = Series._from_mgr(mgr, axes=axes) ser._name = None # caller is responsible for setting real name return ser else: diff --git a/pandas/tests/frame/test_subclass.py b/pandas/tests/frame/test_subclass.py index 55bfefaeb53a9..f19e31002c877 100644 --- a/pandas/tests/frame/test_subclass.py +++ b/pandas/tests/frame/test_subclass.py @@ -773,3 +773,44 @@ def test_constructor_with_metadata(): ) subset = df[["A", "B"]] assert isinstance(subset, MySubclassWithMetadata) + + +class SimpleDataFrameSubClass(DataFrame): + """A subclass of DataFrame that does not define a constructor.""" + + +class SimpleSeriesSubClass(Series): + """A subclass of Series that does not define a constructor.""" + + +class TestSubclassWithoutConstructor: + def test_copy_df(self): + expected = DataFrame({"a": [1, 2, 3]}) + result = SimpleDataFrameSubClass(expected).copy() + + assert ( + type(result) is DataFrame + ) # assert_frame_equal only checks isinstance(lhs, type(rhs)) + tm.assert_frame_equal(result, expected) + + def test_copy_series(self): + expected = Series([1, 2, 3]) + result = SimpleSeriesSubClass(expected).copy() + + tm.assert_series_equal(result, expected) + + def test_series_to_frame(self): + orig = Series([1, 2, 3]) + expected = orig.to_frame() + result = SimpleSeriesSubClass(orig).to_frame() + + assert ( + type(result) is DataFrame + ) # assert_frame_equal only checks isinstance(lhs, type(rhs)) + tm.assert_frame_equal(result, expected) + + def test_groupby(self): + df = SimpleDataFrameSubClass(DataFrame({"a": [1, 2, 3]})) + + for _, v in df.groupby("a"): + assert type(v) is DataFrame