[Test] Add test for filelock utility

[yaoyaoding]

This PR adds tests for the filelock utility, to make sure it works well on multiple platforms.

[gemini-code-assist]

Summary of Changes

Hello @yaoyaoding, 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 introduces a new suite of tests for the FileLock utility. The primary goal is to ensure the utility functions correctly and robustly across various platforms, specifically focusing on its ability to manage file locks for concurrent operations and prevent race conditions in multi-process environments.

Highlights

• New Test File: A new test file, tests/python/utils/test_filelock.py, has been added to the codebase.
• Basic Lock Functionality: Tests are included for the fundamental acquire and release operations of the FileLock utility, ensuring correct lock state management.
• Context Manager Testing: The FileLock's behavior as a context manager is thoroughly tested, including proper release even when exceptions occur.
• Exclusive Locking & Concurrency: Comprehensive tests verify that FileLock enforces exclusive access, preventing multiple instances from acquiring the same lock simultaneously. A multi-process test simulates concurrent access to a shared resource to confirm race condition prevention.

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[gemini-code-assist]

Code Review

This pull request introduces a comprehensive test suite for the FileLock utility, which is a great addition for ensuring its reliability across different platforms. The tests cover basic functionality, context manager usage, and concurrent access patterns. My review focuses on improving the correctness and robustness of these new tests. I've identified a couple of high-severity issues: one concerning a test that relies on platform-dependent behavior and exposes a resource leak in the underlying implementation, and another regarding a bug in the concurrent test worker that could lead to deadlocks. I've also pointed out a minor issue with a leftover debug print statement.

[yaoyaoding]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds tests for the FileLock utility and makes some related adjustments to the implementation. The tests are comprehensive and cover basic functionality, context manager usage, and multi-process concurrency, which is great. However, I've found a few critical issues in the FileLock implementation itself, particularly around the behavior of blocking_acquire which has an incorrect docstring and a bug related to lock re-acquisition. I've also included some suggestions to improve the new test file's maintainability and robustness.

[yaoyaoding]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds tests for the FileLock utility and introduces non-reentrant behavior for FileLock instances. The tests are comprehensive and cover basic functionality, context manager usage, and multi-process concurrency, which is great. However, the change to make acquire() non-reentrant has introduced a bug in blocking_acquire(), which will now hang until a timeout when called on an already-locked instance. I've provided a suggestion to fix this and make the behavior consistent. I've also pointed out some areas for improvement in documentation clarity and test implementation details. Overall, a good addition with a few critical fixes needed.