[BUG] setup.cfg attr: value is inconsistent between parsing and loading module

setuptools version

setuptools===49.6.0.post20210108

Python version

Python 3.9.2

OS

macOS Catalina

Additional environment information

No response

Description

In https://github.com/pypa/setuptools/blob/b2f7b8f92725c63b164d5776f85e67cc560def4e/setuptools/config.py#L35 StaticModule parses the statements in order to find a relevant assignment, but it should parse statements in reverse order to be consistent with the behavior when loading a module (i.e., the last assignment wins when loading a module).

I think the line should probably read

for statement in reversed(self.module.body)

Expected behavior

I expect the parsing shortcut for finding module attributes to be consistent with loading the module.

How to Reproduce

This inconsistency is illustrated when having a project with a setup.cfg that contains version = attr: mypackage.__version__, where mypackage/__init__.py is

__version__ = "0.1.0"
__version__ = "0.4.0"

With this setup, the version will be 0.1.0, but if the first line is changed to something literal_parse does not understand, forcing setuptools to load the module (like __version__ = "0.1.0" + ""), then the version is 0.4.0.

Output

Code of Conduct

• I agree to follow the PSF Code of Conduct

Start in setuptools/config.py at StaticModule and compare the parsing order with module loading. Reproduce the issue using setup.cfg with attr: mypackage.version and duplicate assignments in mypackage/init.py; done means the parsed value matches Python's last-assignment behavior.