gh-110745: pathlib.Path.read_text add a newline argument

[Okabe-Junya]

gh-110745: pathlib.Path.read_text add a newline argument

• Issue: pathlib.Path.read_text should include a newline argument #110745

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📚 Documentation preview 📚: https://cpython-previews--110880.org.readthedocs.build/

[ghost]

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[bedevere-app]

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[barneygale]

Looking good! Could you also add a test in Lib/test/test_pathlib.py? Maybe have a look at test_write_text_with_newlines :)

[Okabe-Junya]

Thank you for your kind review! I apologize for the delayed response.

As you suggested, I intend to add the appropriate tests. Please give me a moment.

[Okabe-Junya]

Only the test on Windows is failing. I wonder why...

[Okabe-Junya]

Implementing tests using os.linesep seems challenging. Especially on Windows, where the newline code is \r\n, covering this in test cases appears difficult.

Would it be appropriate to separate test cases for each OS?

[barneygale]

Regarding newline=None, this should convert all newlines to \n on read, on all OSs, so your test shouldn't need to reference os.linesep. Maybe something like this?

    def test_read_text_with_newlines(self):
        p = self.cls(BASE, 'fileA')
        p.write_bytes(b'abcde\r\nfghlk\n\rmnopq')
        self.assertEqual(p.read_text(newline=None),   'abcde\nfghlk\n\nmnopq')
        self.assertEqual(p.read_text(newline=''),     'abcde\r\nfghlk\n\rmnopq')
        self.assertEqual(p.read_text(newline='\r'),   'abcde\r\nfghlk\n\rmnopq')
        self.assertEqual(p.read_text(newline='\n'),   'abcde\r\nfghlk\n\rmnopq')
        self.assertEqual(p.read_text(newline='\r\n'), 'abcde\r\nfghlk\n\rmnopq')

[Okabe-Junya]

@barneygale

Thank you for your thoughtful comment!!

I've implemented tests based on your feedback, and they now pass!!

[barneygale]

Sorry for my delayed feedback. Last thing to do is to fix the version number, and give yourself some credit in the changelog if you wish :)

[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.

[Okabe-Junya]

Thank you for your kind review!! (I might not have mentioned properly. I am sorry for that)

I accept your polite suggestion and am ready to merge this. Thank you.

[Okabe-Junya]

I have made the requested changes; please review again

[barneygale]

Looks good, thank you very much!