⚡ Bolt: Optimize context value lookup

[ashyanSpada]

💡 What:
Optimized the Context methods in src/context.rs to avoid redundant Mutex lock lookups and clones. Refactored get() to perform a single HashMap get().cloned() operation instead of getting, checking, then cloning explicitly. Refactored value() to retrieve the cloned ContextValue Option outside of a Mutex lock and pattern match on the result to return the owned variables or execute closures safely without holding the main Context's Mutex lock.

🎯 Why:
The original code performed a double lookup (binding.get(name).is_none() followed by binding.get(name).unwrap()) and, more critically, held the Mutex lock across the execution of a dynamic function (func(Vec::new())). Holding a lock while executing external/inner functions causes lock contention, hurts concurrency, and risks potential deadlocks. This change avoids redundant heap allocations (cloning) and limits the time the Mutex is locked.

📊 Impact:

• Prevents double HashMap lookups.
• Removes redundant .clone() calls on internally matched variables within ContextValue.
• Significantly reduces the time the Mutex is locked.
• Improves performance of execute_expression by ~2.5% according to cargo bench.

🔬 Measurement:

• Run cargo test to ensure existing semantics remain correct.
• Run cargo bench --bench execute_expression to observe performance improvements in the lookup path.

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PR created automatically by Jules for task 8057822893865653070 started by @ashyanSpada

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[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 significantly enhances the performance and concurrency of the Context value lookup mechanisms. By refactoring key methods, it eliminates redundant operations and minimizes the duration of Mutex locks, leading to a more efficient and scalable system. These changes prevent double HashMap lookups, reduce unnecessary cloning, and improve overall execution speed, particularly for expression evaluation.

Highlights

• Context Method Optimization: Optimized Context methods in src/context.rs to eliminate redundant Mutex lock lookups and object cloning.
• get() Method Refactoring: Refactored the get() method to perform a single HashMap::get().cloned() operation, simplifying the lookup process.
• value() Method Concurrency Improvement: Refactored the value() method to retrieve ContextValue outside the Mutex lock, reducing lock contention by releasing the lock before executing functions or cloning variables.

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[gemini-code-assist]

Code Review

This pull request introduces a new learning entry in .jules/bolt.md regarding avoiding double lookups and lock contention in Context lookups. The src/context.rs file has been refactored to implement these learnings, specifically by optimizing the get method to use cloned() directly on the HashMap lookup, thereby reducing lock duration and avoiding redundant lookups. The get_func, get_variable, and value methods have been updated to leverage this improved get method, simplifying their logic and enhancing efficiency. There is no feedback to provide as no review comments were made.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.17%. Comparing base (6cf9bef) to head (6779685).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #46      +/-   ##
==========================================
+ Coverage   88.74%   89.17%   +0.42%     
==========================================
  Files          11       11              
  Lines        1066     1062       -4     
==========================================
+ Hits          946      947       +1     
+ Misses        120      115       -5     

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[Copilot]

Pull request overview

This PR optimizes Context lookups in src/context.rs by reducing redundant HashMap accesses and ensuring the Mutex is not held while executing stored functions, improving concurrency and slightly improving benchmark performance.

Changes:

• Refactored Context::get() to perform a single get(...).cloned() operation under the lock.
• Refactored Context::value() to clone the ContextValue under lock and execute stored functions after the lock is released.
• Updated internal “Bolt” notes documenting the optimization guidance.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/context.rs	Reduces lookups/clones and avoids holding the mutex while calling stored functions.
.jules/bolt.md	Documents the learning/action items for the optimization.

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[Copilot]

In the “Learning” bullet, the double-lookup is caused by calling binding.get(name) twice (e.g., is_none() then get().unwrap()), not by calling get(name) and then .unwrap() on the returned Option. Consider rewording to avoid implying that Option::unwrap() performs another HashMap lookup.

Suggested change

	**Learning:** `HashMap::get(name)` followed by `.unwrap()` inside a Mutex lock not only does double lookup but keeps the lock longer than necessary when executing an inner function or cloning a value.
	**Learning:** Performing two separate `HashMap::get(name)` calls (for example, calling `binding.get(name).is_none()` and then `binding.get(name).unwrap()`) inside a Mutex lock causes a double lookup and keeps the lock longer than necessary when executing an inner function or cloning a value.