perf: optimize linker path processing and validation

[yacosta738]

This change optimizes two allocation hot spots in the linker.rs module.

The first optimization is in for_each_nested_glob_match, which is used during recursive file discovery for NestedGlob targets. It replaces a chain of components().map().collect().join("/") with a more direct to_string_lossy() and a conditional backslash replacement. On Unix, this is now zero-allocation, and on Windows, it performs exactly one allocation.

The second optimization is in ensure_safe_destination, which is called for every target. It removes a redundant collect::<Vec<_>>() call and instead iterates over the path.components() iterator directly.

Both changes reduce heap pressure and improve the overall efficiency of the synchronization engine, especially in large monorepos with many files.

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PR created automatically by Jules for task 5246677227998985419 started by @yacosta738

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 61d08795-5918-4a1a-a868-54a369f07fca

📥 Commits

Reviewing files that changed from the base of the PR and between 8aed5a3 and 5a89a94.

📒 Files selected for processing (1)

• src/linker.rs

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📝 Walkthrough

Summary by CodeRabbit

• Refactor
  • Optimized path handling logic to reduce memory allocations and improve performance.
  • Enhanced cross-platform compatibility for glob matching operations through improved separator normalization.

Walkthrough

The linker module was optimized to reduce memory allocations and simplify string generation. In ensure_safe_destination, intermediate vector allocation was eliminated by directly iterating path components. In for_each_nested_glob_match, relative path string construction now uses to_string_lossy() with separator normalization instead of collect-join operations.

Changes

Cohort / File(s)	Summary
Linker optimizations src/linker.rs	Removed intermediate Vec allocation in ensure_safe_destination by switching to direct component iteration; replaced collect-join string generation with to_string_lossy() and separator normalization in for_each_nested_glob_match; updated comments accordingly.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 Hopping through the linker code,
Vec allocations lighten the load,
Path components dance so free,
No collect-join, just efficiency!
Separators normalized with care,
Faster hops through the air! ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'perf: optimize linker path processing and validation' clearly and concisely summarizes the main change—optimizing path processing and validation in the linker module.
Description check	✅ Passed	The description provides detailed context about the optimizations in linker.rs, explaining the specific changes to both ensure_safe_destination and for_each_nested_glob_match functions and their performance benefits.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

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🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch perf-optimize-linker-allocs-5246677227998985419

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[sentry]

Codecov Report

❌ Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/linker.rs	83.33%	1 Missing ⚠️

📢 Thoughts on this report? Let us know!

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
83.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud