gh-113056: Add a new parameter *compact* to plistlib.dump

[Wulian233]

compact=False (default)

compact=True (new)

• Issue: Please add a compact mode for plistlib serialisation #113056

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📚 Documentation preview 📚: https://cpython-previews--126075.org.readthedocs.build/

[nineteendo]

Wouldn't indent=None like json.dumps() be more flexible?

[Wulian233]

indent=0 (edit) will also add line breaks. compact will not, the same parameter (and function) is also present in pprint.

https://docs.python.org/3.14/library/json.html#basic-usage
https://docs.python.org/3.14/library/pprint.html#functions

Also exist in json.tool

Use with --no-indent or --compact to produce valid JSON Lines output.')

https://github.com/python/cpython/blob/main/Lib/json/tool.py#L27-L27

[nineteendo]

No, that's indent=0:

An indent level of 0, negative, or "" will only insert newlines. None (the default) selects the most compact representation.

[devdanzin]

Would it make sense to test that when compact=True indentation/newlines are absent in the output? And maybe test that the compact output is shorter that the non-compact?

[serhiy-storchaka]

I am not a macOS user, so I have no opinion about this feature.

[nineteendo]

Wulian, you still haven't responded to why we can't add indent="\t" instead, this is familiar to uses of the json library.

[Wulian233]

I think setting compact=True would be easier to understand the purpose, and pprint also has this feature, which outputs a format without indentation and line breaks.

Same name also exist in json.tool

Use with --no-indent or --compact to produce valid JSON Lines output.')

https://github.com/python/cpython/blob/main/Lib/json/tool.py#L27-L27

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indent=0 and indent=None are not very clear, and the difference is adding line breaks, just like me, I got confused about the difference between the two in the above. I added this function mentioned it in the issue, where indentation takes up a lot of space, of course, adding indent would be more flexible, and using compact would be more direct, and indent="\t" feels like it's getting complicated again. I haven't used plist, but XML format is usually indented with four spaces?

[nineteendo]

pprint also has this feature, which outputs a format without indentation and line breaks.

compact for pprint() formats the elements in a grid layout. "compact" is width=sys.maxsize.

[thierryba]

any news on this front ? That would be a super valuable feature

[github-actions]

This PR is stale because it has been open for 30 days with no activity.