perf(transform): O(1) class-chain lookups in inliner shadowing analysis

[TheHypnoo]

Replaces the O(classes) linear scan per inheritance level in the inliner's method-shadowing analysis with O(1) hash lookups.

What

method_lookup_is_unshadowed and class_chain_property_sets (crates/perry-transform/src/inline/analysis.rs) walk the class inheritance chain (depth capped at 32) and at every level did classes.iter().find(|c| c.name == name) — an O(number-of-classes) scan. Both functions are called once per inlinable-method candidate (from inline/mod.rs and inline/cross_module.rs), so candidate evaluation was effectively O(candidates × depth × classes). On modules with many classes and deep hierarchies (e.g. Effect-style codebases) this is wasted compile time.

This indexes the class slice by name into a HashMap<&str, &Class> once per call and does O(1) lookups during the walk.

Correctness

HashMap::entry(...).or_insert(c) keeps the first class for a duplicate name, exactly matching the prior iter().find() first-match semantics. This matters: duplicate class names occur across modules (e.g. Effect's same-named Type in SchemaAST and ParseResult). Compiler output is unchanged — only lookup complexity drops.

Verification

• cargo test --release -p perry-transform — all pass (30 tests).
• Built the full driver and compiled/ran a 3-level inheritance program with method overriding and inlining; output is correct (overrides resolve to the right method, inherited methods reach the base implementation).

Pure compile-speed change; no runtime or codegen-output behavior change.

Summary by CodeRabbit

• Refactor
  • Optimized class name resolution in method-lookup and property-set validation checks for improved performance.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: cfdef94f-be66-469b-84a2-7bb904c08748

📥 Commits

Reviewing files that changed from the base of the PR and between 06caf3d and b0a8617.

📒 Files selected for processing (1)

• crates/perry-transform/src/inline/analysis.rs

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📝 Walkthrough

Walkthrough

This PR optimizes class-lookup performance in the inline analysis module by replacing repeated linear searches over class lists with pre-built HashMap indices keyed by class name. Both method_lookup_is_unshadowed and class_chain_property_sets now build and use an indexed map during prototype-chain walks to resolve classes in constant time rather than linear time.

Changes

Inline Analysis Class Lookup Optimization

Layer / File(s)	Summary
Hash-based class lookup in analysis functions crates/perry-transform/src/inline/analysis.rs	method_lookup_is_unshadowed and class_chain_property_sets replace per-step linear searches with a pre-built HashMap indexed by class name, using entry(...).or_insert(...) to preserve "first duplicate" semantics and get() for O(1) lookups during prototype-chain walks.

🎯 1 (Trivial) | ⏱️ ~5 minutes

🐰 A rabbit hops with glee,
Hash maps now, no more linear spree!
Class lookups swift and bright,
Prototype chains run right! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the main change: performance optimization of class-chain lookups from linear to O(1) hash lookups in the inliner's shadowing analysis.
Description check	✅ Passed	The description is comprehensive and follows the template structure with clear Summary, What, Correctness, and Verification sections covering all essential aspects of the change.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch perf/inline-class-chain-lookup

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