ARROW-17176: [Rust] Activate generate_decimal256_case integration test for rust

[viirya]

arrow-rs has added decimal256 support recently. We should activate generate_decimal256_case integration test.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-17176

[github-actions]

⚠️ Ticket has not been started in JIRA, please click 'Start Progress'.

[viirya]

cc @alamb

[alamb]

🎉 🦜

[viirya]

@alamb Can you help merge this? If you are busy, please let me know how to merge this. Thanks. 😄

[alamb]

Hi @viirya -- I think we can just merge. Thanks!

[alamb]

I will watch https://github.com/apache/arrow/runs/7585938940?check_suite_focus=true and https://github.com/apache/arrow/runs/7585938943?check_suite_focus=true to make sure they pass -- and if not I will revert this PR

[viirya]

Thank you @alamb !

[viirya]

Ah, there was a failure:

Error: InvalidArgumentError("-555221045220379430784912070743352079671 is too small to store in a Decimal256 of precision 39. Min is -99999999999999999999999999999999999999")

Because we add value validation recently.

Like Decimal128 case, we also need to disable validation for Decimal256 case for this integration.

Proposed a fix at apache/arrow-rs#2232

cc @alamb

[ursabot]

Benchmark runs are scheduled for baseline = 778d574 and contender = f4c0cda. f4c0cda is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Failed ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Finished ⬇️0.44% ⬆️0.0%] test-mac-arm
[Failed ⬇️0.54% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️0.14% ⬆️0.0%] ursa-thinkcentre-m75q
Buildkite builds:
[Failed] f4c0cda0 ec2-t3-xlarge-us-east-2
[Finished] f4c0cda0 test-mac-arm
[Finished] f4c0cda0 ursa-i9-9960x
[Finished] f4c0cda0 ursa-thinkcentre-m75q
[Failed] 778d574b ec2-t3-xlarge-us-east-2
[Finished] 778d574b test-mac-arm
[Failed] 778d574b ursa-i9-9960x
[Finished] 778d574b ursa-thinkcentre-m75q
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[alamb]

Thanks @viirya -- as I mentioned in apache/arrow-rs#2232 (review) something seems strange if the integration test is using invalid values for Decimal -- either the integration test should be fixed or maybe we have mis-interpreted what is valid in the Rust implementation 🤔

[nealrichardson]

FYI @zeroshade

[viirya]

@alamb Ah, sorry, after rechecking it, I made a mistake when filling maximum and minimum decimal values for precision > 38. So for generate_decimal256_case it is a false alarm. Sorry for confusion.

[viirya]

Going to fix it at apache/arrow-rs#2245

[alamb]

Thank you @viirya !