refactor(allocator)!: put AllocatorPool behind pool feature

[overlookmotel]

AllocatorPool is only used in linter. Parser, transformer, minifier etc don't need it. So put it behind a pool cargo feature.

This complicates the many #[cfg] attrs even further, but this is preparation for merging the 2 AllocatorPool implementations, and removing the fixed_size feature, which will remove a lot of this #[cfg] mess.

[overlookmotel]

• refactor(allocator)!: put AllocatorPool behind pool feature #13373 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR refactors the AllocatorPool to be conditionally compiled behind a pool feature, optimizing dependencies for components that don't need pooled allocation functionality. The change reduces bloat for parser, transformer, minifier and other components while allowing the linter to explicitly opt into pool functionality.

• Adds a new pool cargo feature to oxc_allocator
• Updates conditional compilation attributes to gate AllocatorPool behind the pool feature
• Enables the pool feature in oxc_linter which requires AllocatorPool

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
crates/oxc_linter/Cargo.toml	Explicitly enables the pool feature for the allocator dependency
crates/oxc_allocator/src/lib.rs	Updates #[cfg] attributes to conditionally compile pool-related code behind the pool feature
crates/oxc_allocator/README.md	Documents the new pool feature
crates/oxc_allocator/Cargo.toml	Defines the new pool feature and makes fixed_size depend on it

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13373 will not alter performance

_{Comparing 08-29-refactor_allocator_put_allocatorpool_behind_pool_feature (df8e639) with main (13470b2)¹}

Summary

✅ 38 untouched benchmarks

Footnotes

1. No successful run was found on main (df8e639) during the generation of this report, so 13470b2 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[overlookmotel]

Merge activity

• Aug 29, 4:50 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Aug 29, 4:50 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Aug 29, 4:56 PM UTC: Merged by the Graphite merge queue.