Add improved static type checking in setup.py

[kibablu]

Add static type checking on setup.py with Any as the path-like object is either str or bytes object representing a path, or an object implementing the os path.

[callahad]

I'm surprised this is failing.

Let me test if I can get this to blow up locally, and if so, whether adding from __future__ import annotations fixes it or if there's something else we need to do.

[callahad]

Okay, yep. This is failing for a very obscure reason. Python 3.7 and 3.8 don't understand the [str] part of PathLike[str], and so they throw an error.

We can fix that by opting into new behaviors for type annotations. Making the following change should get the tests to pass:

diff --git a/setup.py b/setup.py
index 88a79f5..2e91d7a 100755
--- a/setup.py
+++ b/setup.py
@@ -16,9 +16,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.

-from typing import Union
-from os import PathLike
+from __future__ import annotations
+
 import os.path
+from os import PathLike
+from typing import Union

 from setuptools import find_packages, setup

...and since we're using the __future__ import, we can also use the new shorthand syntax for Unions:

diff --git a/setup.py b/setup.py
index 2e91d7a..303c791 100755
--- a/setup.py
+++ b/setup.py
@@ -20,7 +20,6 @@ from __future__ import annotations

 import os.path
 from os import PathLike
-from typing import Union

 from setuptools import find_packages, setup

@@ -29,7 +28,7 @@ from setuptools import find_packages, setup
 # Used for the long_description.  It's nice, because now 1) we have a top level
 # README file and 2) it's easier to type in the README file than to put a raw
 # string in below ...
-def read(fname: Union[str, PathLike[str]]) -> str:
+def read(fname: str | PathLike[str]) -> str:
     return open(os.path.join(os.path.dirname(__file__), fname)).read()

[kibablu]

Thank you @callahad :smiley: :tada: :tada: