Drop extra copy in get_last_error_text

[jakirkham]

In get_last_error_text, the assignment of const char* to bytes results in a copy as bytes must own its memory. After the bytes object is decoded to a Python str. However it is possible to decode directly from const char* to str avoiding the copy to the temporary bytes object. Hence this code makes that change.

Further Python and Cython def functions always return None if nothing else is returned. Hence the logic can be simplified here to only focus on returning the error text.

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📥 Commits

Reviewing files that changed from the base of the PR and between f4e7894 and 243e4e1.

📒 Files selected for processing (1)

• python/cuvs/cuvs/common/exceptions.pyx

🚧 Files skipped from review as they are similar to previous changes (1)

• python/cuvs/cuvs/common/exceptions.pyx

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📝 Walkthrough

Summary by CodeRabbit

• Refactor
  • Streamlined error-text handling: decoding now happens directly when an error is present.
  • Adjusted control flow so the error-text path no longer uses an early-return, reducing intermediate steps and simplifying behavior.

Walkthrough

Refactor of get_last_error_text in the exceptions module: the function now decodes and returns the C error string directly when c_err is non-NULL; the previous explicit NULL early-return was removed so the function falls through when c_err is NULL.

Changes

Cohort / File(s)	Summary
Exception Error Handling python/cuvs/cuvs/common/exceptions.pyx	get_last_error_text simplified to decode and return the C error text directly from c_err when non-NULL; removed intermediate bytes variable and the explicit NULL early-return (function now falls through on NULL).

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: removing an unnecessary copy operation in the get_last_error_text function, which is the core objective of the changeset.
Description check	✅ Passed	The description is directly related to the changeset, explaining the optimization of avoiding a copy via bytes and the simplified control flow, which matches the PR objectives and code changes.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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