sqlite3: reject negative fetchmany values

[ever0de]

Summary by CodeRabbit

• Bug Fixes
  • Improved input validation for the fetchmany operation: negative size arguments are now rejected with a clear error, while omitted sizes fall back to the existing default arraysize. This prevents processing of invalid values and ensures predictable error handling and behavior for callers.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 4b4e56f and 14a34bb.

📒 Files selected for processing (1)

• crates/stdlib/src/_sqlite3.rs

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📝 Walkthrough

Walkthrough

The SQLite3 fetchmany implementation now validates the optional size argument: negative values raise a ValueError; a provided non-negative size is used; when size is None, the cursor's existing arraysize is used as the fallback.

Changes

Cohort / File(s)	Summary
SQLite3 Cursor fetchmany Validation crates/stdlib/src/_sqlite3.rs	Validate optional size in fetchmany; return ValueError for negative sizes, use provided non-negative size, otherwise fall back to cursor arraysize (replaces previous unwrap_or_else behavior).

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Possibly related PRs

• sqlite3: Support 'size' keyword argument in Cursor::fetchmany #6118: Adjusts Cursor::fetchmany handling of optional size/max_rows with explicit validation and arraysize fallback.

Poem

🐰 I nibble code beneath the moonlight bright,
Fetchmany now checks sizes with delight,
No negatives hopping through my gate,
Arraysize waits when none dictate,
A tidy burrow, clean and right.

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: adding validation to reject negative values in the fetchmany function.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

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[github-actions]

📦 Library Dependencies

The following Lib/ modules were modified. Here are their dependencies:

[x] lib: cpython/Lib/sqlite3
[ ] test: cpython/Lib/test/test_sqlite3 (TODO: 81)

dependencies:

• sqlite3

dependent tests: (2 tests)

• sqlite3: test_dbm_sqlite3 test_sqlite3

Legend:

• [+] path exists in CPython
• [x] up-to-date, [ ] outdated

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@crates/stdlib/src/_sqlite3.rs`:
- Line 1889: Fix the typo in the ValueError message emitted by the fetchmany
code path: update the string passed to vm.new_value_error in the fetchmany
return statement (the return Err(vm.new_value_error("fetchmany many not be
negative")) call) to a correct message such as "fetchmany may not be negative"
or "size must not be negative" so the error text is accurate and clear.

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ℹ️ Review info

Configuration used: Path: .coderabbit.yml

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 09cf492 and 4b4e56f.

⛔ Files ignored due to path filters (1)

• Lib/test/test_sqlite3/test_dbapi.py is excluded by !Lib/**

📒 Files selected for processing (1)

• crates/stdlib/src/_sqlite3.rs