GH-46403: [C++] Add support for limiting element size when printing a…

[david1437]

Rationale for this change

#46403

What changes are included in this PR?

A new PrettyPrinter option is added to limit elements to 100 characters by default.

Are these changes tested?

Yes

Are there any user-facing changes?

Yes, the default length for outputted elements when stringifying them is now different so if a user was relying on ToString of an array with large elements that result may now be changed.

• GitHub Issue: [C++] Avoid printing very large values #46403

[github-actions]

⚠️ GitHub issue #46403 has been automatically assigned in GitHub to PR creator.

[pitrou]

Thanks for this @david1437 . This looks good in general, some comments below.

[pitrou]

There is a failure in the Python test suite (see CI results). Can you update the test for the new behavior?

[david1437]

@pitrou this one should be good as well now, only thing is the python test seems to have a different length omitted than I expected? Also it seems cant pass the pretty print options into the python version? not sure how the C++ bindings play into that

[pitrou]

Also it seems cant pass the pretty print options into the python version? not sure how the C++ bindings play into that

If you feel at ease with Cython, you could try to add the options to the Python bindings. Otherwise someone else could do it in another PR.

only thing is the python test seems to have a different length omitted than I expected?

Well, you can try to diagnose the issue?

[david1437]

Not to sure on debugging python bindings calling in to c++, but I'll give it a try!

…

On Wed, May 28, 2025, 3:56 PM Antoine Pitrou ***@***.***> wrote: *pitrou* left a comment (apache/arrow#46536) <#46536 (comment)> Also it seems cant pass the pretty print options into the python version? not sure how the C++ bindings play into that If you feel at ease with Cython, you could try to add the options to the Python bindings. Otherwise someone else could do it in another PR. only thing is the python test seems to have a different length omitted than I expected? Well, you can try to diagnose the issue? — Reply to this email directly, view it on GitHub <#46536 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AGD5HPJOI65DVO5SXMAHN7D3AXFDHAVCNFSM6AAAAAB5UGEU5WVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDSMJWGY2TMMZVGE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[david1437]

Added the python bindings and figured out the test issue with some GDB debugging. Apologies for not looking deeper into it earlier, I was a bit intimidated by the python bindings but it wasnt too bad after all. @pitrou let me know if any other adjustments are needed thanks