chore: move Self to compat module

Signed-off-by: Henry Schreiner <[email protected]>

Author: henryiii

pyproject.toml

@@ -233,6 +233,7 @@ extend-select = [
   "PT",          # flake8-pytest-style
   "PTH",         # flake8-use-pathlib
   "PYI",         # flake8-pyi
+  "TID251",      # flake8-tidy-imports.banned-api
   "RET",         # flake8-return
   "RUF",         # Ruff-specific
   "SIM",         # flake8-simplify
@@ -247,10 +248,13 @@ ignore = [
   "PT011",          # pytest.raises too broad
   "PYI034",         # We are returning Self, just generic
 ]
-typing-modules = ["boost_histogram.typing"]
+typing-modules = ["boost_histogram._compat.typing"]
 isort.required-imports = ["from __future__ import annotations"]
 exclude = ["extern/*"]
 
+[tool.ruff.lint.flake8-tidy-imports.banned-api]
+"typing.Self".msg = "Use boost_histogram._compat.typing.Self instead."
+"typing_extensions.Self".msg = "Use boost_histogram._compat.typing.Self instead."
 
 [tool.ruff.lint.mccabe]
 max-complexity = 13
@@ -261,7 +265,8 @@ max-complexity = 13
 "scripts/*" = ["T20"]
 "tests/*" = ["T20"]
 "notebooks/*" = ["T20"]
-"*.pyi" = ["F401"]
+"*.pyi" = ["F401", "TID251"]
 "docs/conf.py" = ["ARG001"]
 "src/boost_histogram/test.py" = ["PT"]
 "**.ipynb" = ["I002", "E731"]
+"src/boost_histogram/_compat/**.py" = ["TID251"]

src/boost_histogram/_compat/__init__.py

@@ -0,0 +1,14 @@
+import sys
+import typing
+
+if sys.version_info >= (3, 11):
+    from typing import Self
+elif typing.TYPE_CHECKING:
+    from typing_extensions import Self
+else:
+    Self = object
+
+__all__ = ["Self"]
+
+def __dir__() -> list[str]:
+    return __all__

src/boost_histogram/_compat/typing.py

@@ -15,10 +15,10 @@
 )
 
 import numpy as np  # pylint: disable=unused-import
-from typing_extensions import Self
 
 import boost_histogram
 
+from .._compat.typing import Self
 from .._core import axis as ca
 from .._utils import cast, register, zip_strict
 from . import transform

src/boost_histogram/axis/__init__.py

@@ -3,10 +3,9 @@
 import copy
 from typing import Any, ClassVar, TypeVar
 
-from typing_extensions import Self
-
 import boost_histogram
 
+from .._compat.typing import Self
 from .._core import axis as ca
 from .._utils import register
 

src/boost_histogram/axis/transform.py

@@ -22,11 +22,11 @@
 )
 
 import numpy as np
-from typing_extensions import Self
 
 import boost_histogram
 from boost_histogram import _core
 
+from ._compat.typing import Self
 from ._utils import cast, register
 from .axis import AxesTuple, Axis, Variable
 from .storage import Double, Storage
@@ -36,6 +36,7 @@
 if TYPE_CHECKING:
     from builtins import ellipsis
 
+
 try:
     from . import _core
 except ImportError as err:

src/boost_histogram/histogram.py

@@ -12,8 +12,7 @@
 if TYPE_CHECKING:
     from uhi.typing.plottable import PlottableAxis
 
-from typing_extensions import Self
-
+from ._compat.typing import Self
 from .typing import AxisLike
 
 __all__ = ("Locator", "Slicer", "at", "loc", "overflow", "rebin", "sum", "underflow")