fix: panic when reading empty extended-timestamp field (#404)

[Pr0methean]

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[amazon-q-developer]

⏳ Code review in progress. Analyzing for code quality issues and best practices. Detailed findings will be posted upon completion.

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[gemini-code-assist]

Summary of Changes

Hello @Pr0methean, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a critical stability issue by preventing a panic that could occur when processing ZIP archives containing an empty extended timestamp field. The changes introduce explicit error handling for this scenario, ensuring that the zip crate gracefully handles malformed data instead of crashing. This enhancement improves the overall robustness and reliability of the library, particularly important for server-side applications.

Highlights

• Panic Prevention: Implemented a fix to prevent a panic that occurred when attempting to read an empty extended-timestamp field in a ZIP archive.
• Robust Error Handling: Introduced proper error handling by returning an InvalidArchive error when an empty extended timestamp field is encountered, ensuring the application remains stable.
• New Test Case: Added a dedicated test case (test_bad_extended_timestamp) to validate the fix and ensure that malformed extended timestamp data no longer causes a panic.

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[amazon-q-developer]

I've reviewed the changes that fix the panic when reading empty extended-timestamp fields. The core fix is solid and addresses the issue by properly handling empty fields. I've suggested a few improvements:

1. Enhanced error message to provide more context about the invalid field length
2. Better test organization with proper attribute placement
3. More descriptive test assertion message

The changes look good overall and improve the robustness of the ZIP parsing. Please consider the suggested improvements to enhance error reporting and test maintainability.

[gemini-code-assist]

Code Review

This pull request correctly fixes a panic that occurs when reading an empty extended-timestamp field by adding a check for zero length. A regression test is also included, which is great. My review includes a few suggestions to improve the implementation by using crate-idiomatic error handling and to make the new test code more concise.