Added Warning and Exception annotations

numpy-stubs/__init__.pyi

@@ -1,6 +1,7 @@
 import builtins
 import sys
 import datetime as dt
+import warnings as _warnings
 
 from numpy.core._internal import _ctypes
 from typing import (
@@ -778,3 +779,17 @@ trunc: ufunc
 
 # TODO(shoyer): remove when the full numpy namespace is defined
 def __getattr__(name: str) -> Any: ...
+
+# Warnings
+warnings = _warnings
+class ModuleDeprecationWarning(DeprecationWarning): ...
+class VisibleDeprecationWarning(UserWarning): ...
+class ComplexWarning(RuntimeWarning): ...
+class RankWarning(UserWarning): ...
+
+# Errors
+class TooHardError(RuntimeError): ...
+class AxisError(ValueError, IndexError):
+    # Note that all parameters for __init__ (except self) can technically be Any.
+    # So it's a question here whether or not we should allow what's possible or what's intended
+    def __init__(self, axis: int, ndim: Optional[int] = ..., msg_prefix: Optional[str] = ...) -> None: ...

tests/pass/warnings_and_errors.py

@@ -0,0 +1,18 @@
+import types
+from typing import Type
+
+import numpy as np
+
+warnings = np.warnings  # type: types.ModuleType
+ModuleDeprecationWarning = np.ModuleDeprecationWarning  # type: Type[DeprecationWarning]
+VisibleDeprecationWarning = np.VisibleDeprecationWarning  # type: Type[UserWarning]
+ComplexWarning = np.ComplexWarning  # type: Type[RuntimeWarning]
+RankWarning = np.RankWarning  # type: Type[UserWarning]
+
+TooHardError = np.TooHardError  # type: Type[RuntimeError]
+AxisError1 = np.AxisError  # type: Type[ValueError]
+AxisError2 = np.AxisError  # type: Type[IndexError]
+
+np.AxisError(1)
+np.AxisError(1, ndim=2)
+np.AxisError(1, ndim=2, msg_prefix='error')