TYP: Work around a mypy issue with bool arrays (numpy#29248)

jorenham · web-flow · commit 004458d21696 · 2025-06-25T21:41:55.000-06:00
diff --git a/numpy/__init__.pyi b/numpy/__init__.pyi
@@ -3848,14 +3848,14 @@ class bool(generic[_BoolItemT_co], Generic[_BoolItemT_co]):
     @property
     def imag(self) -> np.bool[L[False]]: ...
 
-    @overload
-    def __init__(self: np.bool[L[False]], /) -> None: ...
+    @overload  # mypy bug workaround: https://github.com/numpy/numpy/issues/29245
+    def __init__(self: np.bool[builtins.bool], value: Never, /) -> None: ...
     @overload
     def __init__(self: np.bool[L[False]], value: _Falsy = ..., /) -> None: ...
     @overload
     def __init__(self: np.bool[L[True]], value: _Truthy, /) -> None: ...
     @overload
-    def __init__(self, value: object, /) -> None: ...
+    def __init__(self: np.bool[builtins.bool], value: object, /) -> None: ...
 
     def __bool__(self, /) -> _BoolItemT_co: ...
     @overload
diff --git a/numpy/typing/tests/data/reveal/array_constructors.pyi b/numpy/typing/tests/data/reveal/array_constructors.pyi
@@ -39,6 +39,8 @@ assert_type(np.array(B, subok=True), SubClass[np.float64])
 assert_type(np.array(B, subok=True, ndmin=0), SubClass[np.float64])
 assert_type(np.array(B, subok=True, ndmin=1), SubClass[np.float64])
 assert_type(np.array(D), npt.NDArray[np.float64 | np.int64])
+# https://github.com/numpy/numpy/issues/29245
+assert_type(np.array([], dtype=np.bool), npt.NDArray[np.bool])
 
 assert_type(np.zeros([1, 5, 6]), npt.NDArray[np.float64])
 assert_type(np.zeros([1, 5, 6], dtype=np.int64), npt.NDArray[np.int64])
diff --git a/numpy/typing/tests/data/reveal/ma.pyi b/numpy/typing/tests/data/reveal/ma.pyi
@@ -357,8 +357,7 @@ assert_type(MAR_b.swapaxes(0, 1), MaskedArray[np.bool])
 assert_type(MAR_2d_f4.swapaxes(1, 0), MaskedArray[np.float32])
 
 assert_type(np.ma.nomask, np.bool[Literal[False]])
-# https://github.com/python/mypy/issues/18974
-assert_type(np.ma.MaskType, type[np.bool])  # type: ignore[assert-type]
+assert_type(np.ma.MaskType, type[np.bool])
 
 assert_type(MAR_1d.__setmask__([True, False]), None)
 assert_type(MAR_1d.__setmask__(np.False_), None)
