[wip] - js2py to mini-racer

[derrickaw]

Please add a meaningful description for your change here

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[derrickaw]

/gemini review

[gemini-code-assist]

Summary of Changes

Hello, 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 migrates the JavaScript execution engine used in Beam YAML from js2py to py-mini-racer. This change addresses compatibility issues with newer Python versions and improves the robustness of JavaScript UDF execution by implementing thread-safe context management and better type conversion between JavaScript and Python.

Highlights

• Dependency Migration: Replaced the js2py dependency with py-mini-racer in setup.py to support modern Python versions.
• Implementation Update: Updated yaml_mapping.py to use MiniRacer for JavaScript execution, including a new thread-safe context caching mechanism and a utility to convert JavaScript objects to Python types.
• Test Suite Updates: Updated existing tests to use MiniRacer and added a new test case to verify correct handling of JavaScript Date objects.

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[gemini-code-assist]

Code Review

This pull request replaces the js2py dependency with py_mini_racer for JavaScript mapping functions in Beam YAML, improving compatibility with Python 3.12. The implementation introduces a js_to_py conversion utility and a thread-based caching mechanism for JavaScript contexts. Review feedback suggests optimizing performance by moving local imports to the top level and using threading.local() for context management. Additionally, it is recommended to use the ctx.call API for better argument handling and to rely on standard collection protocols instead of internal library class names for type checking.

[derrickaw]

/gemini review

[gemini-code-assist]

Code Review

This pull request replaces the js2py library with py_mini_racer for executing JavaScript mapping functions in Beam YAML, which improves compatibility with Python 3.12. The changes introduce a thread-local context for JavaScript execution and a new conversion utility, js_to_py, to handle the mapping of JavaScript objects to Python types. Feedback identifies several issues: missing imports for Mapping and Iterable that will cause runtime errors, an unused json import, and a logic flaw in js_to_py that would incorrectly process bytes objects as generic iterables. Additionally, a new test case requires an update to its assertions to match the datetime objects now returned by the implementation.