Merge branch 'main' into issue-50977

Author: kostyafarber

doc/source/whatsnew/v2.0.0.rst

@@ -781,6 +781,7 @@ Deprecations
 - :meth:`Index.is_interval` has been deprecated. Use :func:`pandas.api.types.is_intterval_dtype` instead (:issue:`50042`)
 - Deprecated ``all`` and ``any`` reductions with ``datetime64`` and :class:`DatetimeTZDtype` dtypes, use e.g. ``(obj != pd.Timestamp(0), tz=obj.tz).all()`` instead (:issue:`34479`)
 - Deprecated unused arguments ``*args`` and ``**kwargs`` in :class:`Resampler` (:issue:`50977`)
+- Deprecated calling ``float`` or ``int`` on a single element :class:`Series` to return a ``float`` or ``int`` respectively. Extract the element before calling ``float`` or ``int`` instead (:issue:`51101`)
 
 .. ---------------------------------------------------------------------------
 .. _whatsnew_200.prior_deprecations:

pandas/core/internals/managers.py

@@ -409,8 +409,15 @@ def diff(self: T, n: int, axis: AxisInt) -> T:
         axis = self._normalize_axis(axis)
         return self.apply("diff", n=n, axis=axis)
 
-    def interpolate(self: T, **kwargs) -> T:
-        return self.apply("interpolate", **kwargs)
+    def interpolate(self: T, inplace: bool, **kwargs) -> T:
+        if inplace:
+            # TODO(CoW) can be optimized to only copy those blocks that have refs
+            if using_copy_on_write() and any(
+                not self._has_no_reference_block(i) for i in range(len(self.blocks))
+            ):
+                self = self.copy()
+
+        return self.apply("interpolate", inplace=inplace, **kwargs)
 
     def shift(self: T, periods: int, axis: AxisInt, fill_value) -> T:
         axis = self._normalize_axis(axis)

pandas/core/resample.py

@@ -153,7 +153,6 @@ def __init__(
         *,
         group_keys: bool | lib.NoDefault = lib.no_default,
         selection=None,
-        **kwargs,
     ) -> None:
         self._timegrouper = groupby
         self.keys = None
@@ -173,18 +172,6 @@ def __init__(
         else:
             self.exclusions = frozenset()
 
-    @final
-    def _shallow_copy(self, obj, **kwargs):
-        """
-        return a new object with the replacement attributes
-        """
-        if isinstance(obj, self._constructor):
-            obj = obj.obj
-        for attr in self._attributes:
-            if attr not in kwargs:
-                kwargs[attr] = getattr(self, attr)
-        return self._constructor(obj, **kwargs)
-
     def __str__(self) -> str:
         """
         Provide a nice str repr of our rolling object.
@@ -1196,7 +1183,7 @@ def _apply(self, f, *args, **kwargs):
         """
 
         def func(x):
-            x = self._shallow_copy(x, groupby=self._timegrouper)
+            x = self._resampler_cls(x, groupby=self._timegrouper)
 
             if isinstance(f, str):
                 return getattr(x, f)(**kwargs)
@@ -1379,7 +1366,7 @@ class DatetimeIndexResamplerGroupby(_GroupByMixin, DatetimeIndexResampler):
     """
 
     @property
-    def _constructor(self):
+    def _resampler_cls(self):
         return DatetimeIndexResampler
 
 
@@ -1491,7 +1478,7 @@ class PeriodIndexResamplerGroupby(_GroupByMixin, PeriodIndexResampler):
     """
 
     @property
-    def _constructor(self):
+    def _resampler_cls(self):
         return PeriodIndexResampler
 
 
@@ -1519,7 +1506,7 @@ class TimedeltaIndexResamplerGroupby(_GroupByMixin, TimedeltaIndexResampler):
     """
 
     @property
-    def _constructor(self):
+    def _resampler_cls(self):
         return TimedeltaIndexResampler
 
 

pandas/core/series.py

@@ -19,6 +19,7 @@
     cast,
     overload,
 )
+import warnings
 import weakref
 
 import numpy as np
@@ -81,6 +82,7 @@
     Substitution,
     doc,
 )
+from pandas.util._exceptions import find_stack_level
 from pandas.util._validators import (
     validate_ascending,
     validate_bool_kwarg,
@@ -216,6 +218,13 @@ def _coerce_method(converter):
 
     def wrapper(self):
         if len(self) == 1:
+            warnings.warn(
+                f"Calling {converter.__name__} on a single element Series is "
+                "deprecated and will raise a TypeError in the future. "
+                f"Use {converter.__name__}(ser.iloc[0]) instead",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
             return converter(self.iloc[0])
         raise TypeError(f"cannot convert the series to {converter}")
 

pandas/tests/apply/test_invalid_arg.py

@@ -277,15 +277,15 @@ def test_agg_none_to_type():
     df = DataFrame({"a": [None]})
     msg = re.escape("int() argument must be a string")
     with pytest.raises(TypeError, match=msg):
-        df.agg({"a": int})
+        df.agg({"a": lambda x: int(x.iloc[0])})
 
 
 def test_transform_none_to_type():
     # GH#34377
     df = DataFrame({"a": [None]})
     msg = "argument must be a"
     with pytest.raises(TypeError, match=msg):
-        df.transform({"a": int})
+        df.transform({"a": lambda x: int(x.iloc[0])})
 
 
 @pytest.mark.parametrize(

pandas/tests/copy_view/test_methods.py

@@ -1194,6 +1194,22 @@ def test_asfreq_noop(using_copy_on_write):
     tm.assert_frame_equal(df, df_orig)
 
 
+def test_interpolate_creates_copy(using_copy_on_write):
+    # GH#51126
+    df = DataFrame({"a": [1.5, np.nan, 3]})
+    view = df[:]
+    expected = df.copy()
+
+    df.ffill(inplace=True)
+    df.iloc[0, 0] = 100.5
+
+    if using_copy_on_write:
+        tm.assert_frame_equal(view, expected)
+    else:
+        expected = DataFrame({"a": [100.5, 1.5, 3]})
+        tm.assert_frame_equal(view, expected)
+
+
 def test_isetitem(using_copy_on_write):
     df = DataFrame({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]})
     df_orig = df.copy()

pandas/tests/series/test_api.py

@@ -287,3 +287,10 @@ def test_numeric_only(self, kernel, has_numeric_only, dtype):
             else:
                 # reducer
                 assert result == expected
+
+
+@pytest.mark.parametrize("converter", [int, float, complex])
+def test_float_int_deprecated(converter):
+    # GH 51101
+    with tm.assert_produces_warning(FutureWarning):
+        assert converter(Series([1])) == converter(1)

pandas/tests/series/test_constructors.py

@@ -145,10 +145,6 @@ def test_scalar_conversion(self):
         scalar = Series(0.5)
         assert not isinstance(scalar, float)
 
-        # Coercion
-        assert float(Series([1.0])) == 1.0
-        assert int(Series([1.0])) == 1
-
     def test_scalar_extension_dtype(self, ea_scalar_and_dtype):
         # GH 28401