diff --git a/pandas/core/frame.py b/pandas/core/frame.py index 5c510d98596df..afcd4d014316e 100644 --- a/pandas/core/frame.py +++ b/pandas/core/frame.py @@ -656,26 +656,37 @@ class DataFrame(NDFrame, OpsMixin): def _constructor(self) -> Callable[..., DataFrame]: return 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 DataFrame._from_mgr(mgr, axes=axes) - else: - assert axes is mgr.axes + def _constructor_from_mgr(self, mgr, axes) -> DataFrame: + df = DataFrame._from_mgr(mgr, axes=axes) + + if type(self) is DataFrame: + # This would also work `if self._constructor is DataFrame`, but + # this check is slightly faster, benefiting the most-common case. + return df + + elif type(self).__name__ == "GeoDataFrame": + # Shim until geopandas can override their _constructor_from_mgr + # bc they have different behavior for Managers than for DataFrames return self._constructor(mgr) + # We assume that the subclass __init__ knows how to handle a + # pd.DataFrame object. + return self._constructor(df) + _constructor_sliced: Callable[..., Series] = Series - def _sliced_from_mgr(self, mgr, axes) -> Series: - return Series._from_mgr(mgr, axes) + def _constructor_sliced_from_mgr(self, mgr, axes) -> Series: + ser = Series._from_mgr(mgr, axes) + ser._name = None # caller is responsible for setting real name - def _constructor_sliced_from_mgr(self, mgr, axes): - if self._constructor_sliced is Series: - ser = self._sliced_from_mgr(mgr, axes) - ser._name = None # caller is responsible for setting real name + if type(self) is DataFrame: + # This would also work `if self._constructor_sliced is Series`, but + # this check is slightly faster, benefiting the most-common case. return ser - assert axes is mgr.axes - return self._constructor_sliced(mgr) + + # We assume that the subclass __init__ knows how to handle a + # pd.Series object. + return self._constructor_sliced(ser) # ---------------------------------------------------------------------- # Constructors @@ -1403,7 +1414,8 @@ def _get_values_for_csv( na_rep=na_rep, quoting=quoting, ) - return self._constructor_from_mgr(mgr, axes=mgr.axes) + # error: Incompatible return value type (got "DataFrame", expected "Self") + return self._constructor_from_mgr(mgr, axes=mgr.axes) # type: ignore[return-value] # ---------------------------------------------------------------------- @@ -5077,7 +5089,8 @@ def predicate(arr: ArrayLike) -> bool: return True mgr = self._mgr._get_data_subset(predicate).copy(deep=None) - return self._constructor_from_mgr(mgr, axes=mgr.axes).__finalize__(self) + # error: Incompatible return value type (got "DataFrame", expected "Self") + return self._constructor_from_mgr(mgr, axes=mgr.axes).__finalize__(self) # type: ignore[return-value] def insert( self, diff --git a/pandas/core/generic.py b/pandas/core/generic.py index 2a86f75badecd..796357355fef4 100644 --- a/pandas/core/generic.py +++ b/pandas/core/generic.py @@ -336,6 +336,7 @@ def _as_manager(self, typ: str, copy: bool_t = True) -> Self: # fastpath of passing a manager doesn't check the option/manager class return self._constructor_from_mgr(new_mgr, axes=new_mgr.axes).__finalize__(self) + @final @classmethod def _from_mgr(cls, mgr: Manager, axes: list[Index]) -> Self: """ diff --git a/pandas/core/resample.py b/pandas/core/resample.py index 2d430ef4dcff6..0dd808a0ab296 100644 --- a/pandas/core/resample.py +++ b/pandas/core/resample.py @@ -2548,7 +2548,8 @@ def _take_new_index( if axis == 1: raise NotImplementedError("axis 1 is not supported") new_mgr = obj._mgr.reindex_indexer(new_axis=new_index, indexer=indexer, axis=1) - return obj._constructor_from_mgr(new_mgr, axes=new_mgr.axes) + # error: Incompatible return value type (got "DataFrame", expected "NDFrameT") + return obj._constructor_from_mgr(new_mgr, axes=new_mgr.axes) # type: ignore[return-value] else: raise ValueError("'obj' should be either a Series or a DataFrame") diff --git a/pandas/core/series.py b/pandas/core/series.py index c1782206d4b67..6fd019656d207 100644 --- a/pandas/core/series.py +++ b/pandas/core/series.py @@ -662,14 +662,17 @@ def _constructor(self) -> Callable[..., Series]: return 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 = Series._from_mgr(mgr, axes=axes) - ser._name = None # caller is responsible for setting real name + ser = Series._from_mgr(mgr, axes=axes) + ser._name = None # caller is responsible for setting real name + + if type(self) is Series: + # This would also work `if self._constructor is Series`, but + # this check is slightly faster, benefiting the most-common case. return ser - else: - assert axes is mgr.axes - return self._constructor(mgr) + + # We assume that the subclass __init__ knows how to handle a + # pd.Series object. + return self._constructor(ser) @property def _constructor_expanddim(self) -> Callable[..., DataFrame]: @@ -681,18 +684,19 @@ def _constructor_expanddim(self) -> Callable[..., DataFrame]: return DataFrame - def _expanddim_from_mgr(self, mgr, axes) -> DataFrame: + def _constructor_expanddim_from_mgr(self, mgr, axes): from pandas.core.frame import DataFrame - return DataFrame._from_mgr(mgr, axes=mgr.axes) + df = DataFrame._from_mgr(mgr, axes=mgr.axes) - def _constructor_expanddim_from_mgr(self, mgr, axes): - from pandas.core.frame import DataFrame + if type(self) is Series: + # This would also work `if self._constructor_expanddim is DataFrame`, + # but this check is slightly faster, benefiting the most-common case. + return df - if self._constructor_expanddim is DataFrame: - return self._expanddim_from_mgr(mgr, axes) - assert axes is mgr.axes - return self._constructor_expanddim(mgr) + # We assume that the subclass __init__ knows how to handle a + # pd.DataFrame object. + return self._constructor_expanddim(df) # types @property diff --git a/pandas/tests/frame/test_subclass.py b/pandas/tests/frame/test_subclass.py index ef78ae62cb4d6..855b58229cbdb 100644 --- a/pandas/tests/frame/test_subclass.py +++ b/pandas/tests/frame/test_subclass.py @@ -26,6 +26,17 @@ def _constructor(self): class TestDataFrameSubclassing: + def test_no_warning_on_mgr(self): + # GH#57032 + df = tm.SubclassedDataFrame( + {"X": [1, 2, 3], "Y": [1, 2, 3]}, index=["a", "b", "c"] + ) + with tm.assert_produces_warning(None): + # df.isna() goes through _constructor_from_mgr, which we want to + # *not* pass a Manager do __init__ + df.isna() + df["X"].isna() + def test_frame_subclassing_and_slicing(self): # Subclass frame and ensure it returns the right class on slicing it # In reference to PR 9632