Merge pull request #30459 from charris/backport-30456

charris · web-flow · commit 11d9ed27e076 · 2025-12-17T12:29:37.000-07:00
TYP: restore ``generic.__hash__`` (#30456)
diff --git a/numpy/__init__.pyi b/numpy/__init__.pyi
@@ -3670,6 +3670,12 @@ class generic(_ArrayOrScalarCommon, Generic[_ItemT_co]):
     @abstractmethod
     def __new__(cls, /, *args: Any, **kwargs: Any) -> Self: ...
 
+    # NOTE: Technically this doesn't exist at runtime, but it is unlikely to lead to
+    # type-unsafe situations (the abstract scalar types cannot be instantiated
+    # themselves) and is convenient to have, so we include it regardless. See
+    # https://github.com/numpy/numpy/issues/30445 for use-cases and discussion.
+    def __hash__(self, /) -> int: ...
+
     if sys.version_info >= (3, 12):
         def __buffer__(self, flags: int, /) -> memoryview: ...
 
@@ -5728,6 +5734,10 @@ class bytes_(character[bytes], bytes):  # type: ignore[misc]
     @overload
     def __new__(cls, value: str, /, encoding: str, errors: str = "strict") -> Self: ...
 
+    #
+    @override
+    def __hash__(self, /) -> int: ...
+
     #
     def __bytes__(self, /) -> bytes: ...
 
@@ -5737,6 +5747,10 @@ class str_(character[str], str):  # type: ignore[misc]
     @overload
     def __new__(cls, value: bytes, /, encoding: str, errors: str = "strict") -> Self: ...
 
+    #
+    @override
+    def __hash__(self, /) -> int: ...
+
 # See `numpy._typing._ufunc` for more concrete nin-/nout-specific stubs
 @final
 class ufunc:
diff --git a/numpy/typing/tests/data/pass/ndarray_misc.py b/numpy/typing/tests/data/pass/ndarray_misc.py
@@ -9,6 +9,7 @@
 from __future__ import annotations
 
 import operator
+from collections.abc import Hashable
 from typing import Any, cast
 
 import numpy as np
@@ -192,3 +193,7 @@ class IntSubClass(npt.NDArray[np.intp]): ...
 A_void: npt.NDArray[np.void] = np.empty(3, [("yop", float), ("yap", float)])
 A_void["yop"] = A_float[:, 0]
 A_void["yap"] = A_float[:, 1]
+
+# regression test for https://github.com/numpy/numpy/issues/30445
+def f(x: np.generic) -> Hashable:
+    return x
diff --git a/tools/stubtest/allowlist.txt b/tools/stubtest/allowlist.txt
@@ -39,6 +39,8 @@ numpy\.(\w+\.)*integer\.bit_count
 numpy\.(\w+\.)*floating\.as_integer_ratio
 numpy\.(\w+\.)*floating\.is_integer
 numpy\.(\w+\.)*complexfloating\.__complex__
+# https://github.com/numpy/numpy/issues/30445#issuecomment-3665484402
+numpy\.(\w+\.)*generic\.__hash__
 
 # intentionally missing deprecated module stubs
 numpy\.core\._dtype
