GH-47859: [C++] Fix creating union types without type_codes for fields.size() == 128

[dahbka-lis]

Rationale for this change

There is a bug for creating union types with empty type_codes. If fields.size() == 128 (kMaxTypeCode + 1) and type_codes is empty, static_cast<int8_t> returns -128 and internal::Iota generates an empty vector of type codes, but the expected vector is [0, 1, 2, ..., 127], where 127 is kMaxTypeCode.

What changes are included in this PR?

• Added a new internal::Iota function to generate vectors of size = length with values from start.
• Changed internal::Iota call from old parameters to new for creating dense_union and sparse_union types.
• Implemented a new test to detect this error.

Are these changes tested?

Yes, there is a new test.

Are there any user-facing changes?

No.

This PR contains a "Critical Fix".
(b) a bug that caused incorrect or invalid data to be produced

If fields.size() == 128 (kMaxTypeCode + 1), internal::Iota returns an empty vector that cannot validate here:
https://github.com/apache/arrow/blob/main/cpp/src/arrow/type.cc#L1232

• GitHub Issue: [C++] Error with creating union types without type_codes for fields.size() == 128 #47859

[github-actions]

Thanks for opening a pull request!

If this is not a minor PR. Could you open an issue for this pull request on GitHub? https://github.com/apache/arrow/issues/new/choose

Opening GitHub issues ahead of time contributes to the Openness of the Apache Arrow project.

Then could you also rename the pull request title in the following format?

GH-${GITHUB_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

or

MINOR: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - Contributing Overview

[dahbka-lis]

Hi, @kou! Do you know someone who can review this PR? It looks like a bug rather than a "feature"

[raulcd]

Thanks for the PR!
This doesn't fit our definition of MINOR, could you please open an issue for this change? See our definition for MINOR:
https://github.com/apache/arrow/blob/main/CONTRIBUTING.md#minor-fixes
Thanks!

[github-actions]

⚠️ GitHub issue #47859 has been automatically assigned in GitHub to PR creator.