gh-114490: Add check for Mach-O linkage in Lib/platform.py

[aidenfoxivey]

#114490

• Issue: Add support for Mach-O linkage detection in Lib/platform.py #114490

[cpython-cla-bot]

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[bedevere-app]

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If this change has little impact on Python users, wait for a maintainer to apply the skip news label instead.

[aidenfoxivey]

Could be wrong here, but this seems like a minor enough change that no news is needed.

[ronaldoussoren]

The change itself LGTM.

I would prefer a news entry though, adding it is easy enough and does show users that something changed here.

[bedevere-app]

A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phrase I have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

[ronaldoussoren]

BTW. Normally I'd ask for a test as well, but this function is mostly untested at the moment and adding a test for just the linkage on macOS feels wrong to me.

[aidenfoxivey]

The change itself LGTM.

I would prefer a news entry though, adding it is easy enough and does show users that something changed here.

Sounds good! I'll set it right up.

[aidenfoxivey]

BTW. Normally I'd ask for a test as well, but this function is mostly untested at the moment and adding a test for just the linkage on macOS feels wrong to me.

Oh, so it would be helpful to add some tests for this function?

[aidenfoxivey]

I have made the requested changes; please review again

[ronaldoussoren]

BTW. Normally I'd ask for a test as well, but this function is mostly untested at the moment and adding a test for just the linkage on macOS feels wrong to me.

Oh, so it would be helpful to add some tests for this function?

I'm personally not that bothered by not having tests for this function, but better test coverage can help avoiding regressions in the future.

AFAIK the only tests for this function are here:

cpython/Lib/test/test_platform.py

Lines 78 to 86 in 441affc

	def test_architecture(self):
	res = platform.architecture()
	@os_helper.skip_unless_symlink
	@support.requires_subprocess()
	def test_architecture_via_symlink(self): # issue3762
	with support.PythonSymlink() as py:
	cmd = "-c", "import platform; print(platform.architecture())"
	self.assertEqual(py.call_real(*cmd), py.call_link(*cmd))

Tests will inherently have platform specifics in them, for other functions in platform the tests themselves are cross-platform by mocking functions used the test. For platform.architecture just mocking _syscmd_file should be good enough. This does require access to a number of platforms to collect data though.

[ronaldoussoren]

The linting job found a formatting niggle in the news entry, see the suggested change below.

With that change the PR is good to go.

[aidenfoxivey]

I have made the requested changes; please review again

[ronaldoussoren]

LGTM

[ronaldoussoren]

@aidenfoxivey, thanks for your PR!