TYP: Series/DataFrame/Index are not Hashable

pandas-stubs/_typing.pyi

@@ -200,5 +200,5 @@ XMLParsers = Literal["lxml", "etree"]
 # Any plain Python or numpy function
 Function = Union[np.ufunc, Callable[..., Any]]
 GroupByObject = Union[
-    Label, List[Label], Function, Series, np.ndarray, Mapping[Label, Any]
+    Label, List[Label], Function, Series, np.ndarray, Mapping[Label, Any], Index
 ]

pandas-stubs/core/frame.pyi

@@ -5,6 +5,7 @@ import datetime as _dt
 from typing import (
     Any,
     Callable,
+    ClassVar,
     Dict,
     Hashable,
     Iterable,
@@ -183,6 +184,8 @@ class DataFrame(NDFrame, OpsMixin):
         Index,
         Series,
     ]
+    __hash__: ClassVar[None]  # type: ignore[assignment]
+
     def __new__(
         cls,
         data: Optional[Union[_ListLike, DataFrame, Dict[Any, Any]]] = ...,
@@ -428,7 +431,7 @@ class DataFrame(NDFrame, OpsMixin):
         *,
         axis: Axis = ...,
         index: Hashable | Sequence[Hashable] = ...,
-        columns: Hashable | Sequence[Hashable] = ...,
+        columns: Hashable | Sequence[Hashable] | Index = ...,
         level: Optional[Level] = ...,
         inplace: Literal[True],
         errors: IgnoreRaise = ...,
@@ -440,7 +443,7 @@ class DataFrame(NDFrame, OpsMixin):
         *,
         axis: Axis = ...,
         index: Hashable | Sequence[Hashable] = ...,
-        columns: Hashable | Sequence[Hashable] = ...,
+        columns: Hashable | Sequence[Hashable] | Index = ...,
         level: Optional[Level] = ...,
         inplace: Literal[False] = ...,
         errors: IgnoreRaise = ...,
@@ -452,7 +455,7 @@ class DataFrame(NDFrame, OpsMixin):
         *,
         axis: Axis = ...,
         index: Hashable | Sequence[Hashable] = ...,
-        columns: Hashable | Sequence[Hashable] = ...,
+        columns: Hashable | Sequence[Hashable] | Index = ...,
         level: Optional[Level] = ...,
         inplace: bool = ...,
         errors: IgnoreRaise = ...,

pandas-stubs/core/generic.pyi

@@ -2,6 +2,7 @@ import sys
 from typing import (
     Any,
     Callable,
+    ClassVar,
     Dict,
     Hashable,
     Iterator,
@@ -89,7 +90,7 @@ class NDFrame(PandasObject, indexing.IndexingMixin):
     def bool(self) -> _bool: ...
     def __abs__(self) -> NDFrame: ...
     def __round__(self, decimals: int = ...) -> NDFrame: ...
-    def __hash__(self): ...
+    __hash__: ClassVar[None]  # type: ignore[assignment]
     def __iter__(self) -> Iterator: ...
     def keys(self): ...
     def iteritems(self): ...

pandas-stubs/core/indexes/base.pyi

@@ -1,5 +1,6 @@
 from typing import (
     Callable,
+    ClassVar,
     Dict,
     Hashable,
     Iterable,
@@ -169,7 +170,7 @@ class Index(IndexOpsMixin, PandasObject):
     def where(self, cond, other=...): ...
     def is_type_compatible(self, kind) -> bool: ...
     def __contains__(self, key) -> bool: ...
-    def __hash__(self) -> int: ...
+    __hash__: ClassVar[None]  # type: ignore[assignment]
     def __setitem__(self, key, value) -> None: ...
     @overload
     def __getitem__(

pandas-stubs/core/indexes/frozen.pyi

@@ -8,4 +8,4 @@ class FrozenList(PandasObject, list):
     def __eq__(self, other) -> bool: ...
     def __mul__(self, other): ...
     def __reduce__(self): ...
-    def __hash__(self): ...
+    def __hash__(self) -> int: ...  # type: ignore[override]

pandas-stubs/core/series.pyi

@@ -5,6 +5,7 @@ from datetime import (
 from typing import (
     Any,
     Callable,
+    ClassVar,
     Dict,
     Generic,
     Hashable,
@@ -138,6 +139,8 @@ class _LocIndexerSeries(_LocIndexer, Generic[S1]):
 class Series(IndexOpsMixin, NDFrame, Generic[S1]):
 
     _ListLike = Union[ArrayLike, Dict[_str, np.ndarray], List, Tuple, Index]
+    __hash__: ClassVar[None]
+
     @overload
     def __new__(
         cls,

tests/__init__.py

@@ -0,0 +1,27 @@
+import typing_extensions
+import types
+
+
+def assert_type(actual_object, expected):
+    # rough check whether the types might match
+
+    actual = type(actual_object).__name__.split(".")[-1]
+    error = False
+
+    if isinstance(expected, types.GenericAlias):  # type: ignore[attr-defined]
+        expected = expected.__name__
+
+    if isinstance(expected, str):
+        actual = actual.lower()
+        expected = expected.lower()
+        error = actual not in expected
+    elif expected is None:
+        error = actual_object is not None
+    else:
+        error = not isinstance(actual_object, expected)
+
+    if error:
+        raise TypeError(f"Expected '{expected}' got '{actual}'")
+
+
+typing_extensions.assert_type = assert_type

tests/test_frame.py

@@ -1141,3 +1141,13 @@ def test_frame_ndarray_assignmment() -> None:
 
     df_b = pd.DataFrame({"a": [0.0] * 10, "b": [1.0] * 10})
     df_b.iloc[:, :] = np.array([[-1.0, np.inf]] * 10)
+
+
+def test_not_hashable() -> None:
+    # GH 113
+    assert_type(pd.DataFrame.__hash__, None)
+    assert_type(pd.DataFrame().__hash__, None)
+    assert_type(pd.Series.__hash__, None)
+    assert_type(pd.Series([], dtype=object).__hash__, None)
+    assert_type(pd.Index.__hash__, None)
+    assert_type(pd.Index([]).__hash__, None)

tests/test_indexes.py

@@ -8,9 +8,9 @@ def test_index_unique() -> None:
 
     df = pd.DataFrame({"x": [1, 2, 3, 4]}, index=pd.Index([1, 2, 3, 2]))
     ind = df.index
-    assert_type(ind, "pd.Index")
+    assert_type(ind, pd.Index)
     i2 = ind.unique()
-    assert_type(i2, "pd.Index")
+    assert_type(i2, pd.Index)
 
 
 def test_index_isin() -> None: