🐛 bug: Guard Binds decoder sync.Pool

[gaby]

Summary

• protect the global decoder pool registry with an RWMutex and helper accessors
• ensure decoder retrieval uses the synchronized registry during parsing
• add concurrency-focused tests that mutate SetParserDecoder while binding to confirm safety

[coderabbitai]

Note

Other AI code review bot(s) detected

CodeRabbit has detected other AI code review bot(s) in this pull request and will avoid duplicating their findings in the review comments. This may lead to a less comprehensive review.

Walkthrough

Introduces concurrency-safe per-tag decoder pools guarded by a package-level mutex and accessed via a new getDecoderPool(tag) function. SetParserDecoder and init acquire write locks when updating pools. Tests added to validate concurrent access and proper pool usage.

Changes

Cohort / File(s)	Summary
Core pool management binder/mapping.go	Adds decoderPoolMu mutex and decoderPoolMap handling via getDecoderPool(tag); getDecoderPool panics if pool uninitialized; SetParserDecoder() and init() now take write locks; parseToStruct() and other callers use getDecoderPool(...).Get()/Put() with defer to ensure Put.
Tests / concurrency validation binder/mapping_test.go	Adds TestSetParserDecoderConcurrentAccess() to exercise concurrent SetParserDecoder + decode usage; updates Test_decoderPoolMapInit() to use getDecoderPool(...) and properly Put() decoders; adds t.Parallel() and imports (fmt, sync).

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Poem

🐇 I dug a hole where mutexes play,

Pools lined up, no races today.
Decoders hop in, fetched with care,
Returned in time — concurrency fair.
Cheers from a rabbit, threads all square 🥕✨

Pre-merge checks and finishing touches

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The PR description is significantly incomplete compared to the template, missing most required sections like Changes introduced, Type of change checklist, and comprehensive Checklist items.	Expand the description to include: explicit type of change selection, detailed changes introduced section, completed checklist items (tests added, self-review comments), and confirmation of passing tests.
Docstring Coverage	⚠️ Warning	Docstring coverage is 25.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: adding synchronization/guarding to the decoder sync.Pool for thread safety. It directly relates to the changeset's focus on concurrency-safe decoder pool access.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch add-synchronization-to-decoderpoolmap

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[gemini-code-assist]

Summary of Changes

Hello @gaby, 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 resolves a concurrency bug within the global decoder pool registry by implementing robust synchronization mechanisms. It introduces a read-write mutex to manage concurrent access to the decoder map, ensuring that both read and write operations are thread-safe. A new helper function streamlines safe decoder retrieval, and existing functions for pool initialization and configuration are updated to leverage these new locking primitives. The changes are thoroughly validated with dedicated concurrency tests to guarantee stability in multi-threaded environments.

Highlights

• Concurrency Control: Introduced a sync.RWMutex (decoderPoolMu) to protect the global decoderPoolMap, ensuring thread-safe access to the decoder registry.
• Synchronized Decoder Retrieval: Added a new helper function getDecoderPool which uses a read lock (RLock) to safely retrieve decoders from the pool, preventing race conditions during concurrent reads.
• Thread-Safe Pool Modification: Modified SetParserDecoder and the init() function to acquire a write lock (Lock) before modifying the decoderPoolMap, ensuring exclusive access during updates.
• Updated Decoder Usage: The parseToStruct function now utilizes the new getDecoderPool helper for fetching decoders, integrating the concurrency guard into the parsing logic.
• Concurrency Testing: Added a new comprehensive test, TestSetParserDecoderConcurrentAccess, to specifically validate the thread-safety of SetParserDecoder and parseToStruct under concurrent operations.

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[chatgpt-codex-connector]

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[gemini-code-assist]

Code Review

This pull request addresses a potential race condition by introducing an RWMutex to protect the global decoder pool registry. The changes are well-structured, with helper functions for synchronized access and a new concurrency test to validate the fix. My review includes two main points: one suggestion to improve the robustness of the new getDecoderPool function, and a critical fix for the new concurrency test which uses a non-standard, experimental Go feature that will cause build failures for most contributors.

[codecov]

Codecov Report

❌ Patch coverage is 80.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.59%. Comparing base (032ff5f) to head (ff9f4e2).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
binder/mapping.go	80.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3969      +/-   ##
==========================================
- Coverage   91.67%   91.59%   -0.09%     
==========================================
  Files         119      119              
  Lines       10177    10207      +30     
==========================================
+ Hits         9330     9349      +19     
- Misses        536      544       +8     
- Partials      311      314       +3     

Flag	Coverage Δ
unittests	91.59% <80.00%> (-0.09%)	⬇️

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[Copilot]

Pull request overview

This PR adds concurrency protection to the global decoder pool registry to prevent race conditions when SetParserDecoder is called concurrently with parser operations.

Key changes:

• Introduced an RWMutex to protect concurrent access to decoderPoolMap
• Added a getDecoderPool helper function to safely retrieve decoder pools
• Updated parsing logic to use the synchronized helper instead of direct map access

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
binder/mapping.go	Added decoderPoolMu RWMutex and getDecoderPool helper for thread-safe pool access; protected SetParserDecoder and init() with write locks; updated parseToStruct to use synchronized pool retrieval
binder/mapping_test.go	Added concurrency test that exercises concurrent SetParserDecoder calls alongside parsing operations; updated existing pool test to use new getDecoderPool helper

[Copilot]

@gaby I've opened a new pull request, #3970, to work on those changes. Once the pull request is ready, I'll request review from you.