Type-soundness and formatting cleanup on top of #80

[scottmessinger]

Summary

Correctness and formatting cleanup on top of the kernel-allocations work in #80. No perf changes — strictly type-soundness, formatting, and one accidental indentation regression.

What this fixes

1. as any casts regressing #76's type-soundness sweep

Three casts to any were introduced when adding intrusive symbol storage:

• packages/kernel/src/collections.ts — createReactiveMap and createReactiveSet use (rawTarget as any)[$PROXY] to read the intrusive cache.
• packages/kernel/src/read.ts — getMutatorCache uses (target as any)[$MUTATORS].

The codebase already has a ReactiveTagged interface in core.ts for exactly this purpose, and #76 deliberately removed as any from this surface. Reintroducing them here was a regression.

Fix: route all three through ReactiveTagged, and add [$MUTATORS]? to the interface so the cast resolves to a real type instead of needing another as any to land somewhere.

2. packages/js-krauset/package.json indent regression

The base reformatted this file from 2-space to 4-space indentation. Every other package.json in the workspace uses 2-space, so this looks accidental. Reverted.

3. perf-stats.ts formatting

Two stats(...) calls added with --trim exceed the line width. pnpm format reformats them on a clean run, so committing them in formatted shape avoids future churn.

What this is not

• No perf changes. No allocation refactors. No structural rewrites.
• The intrusive-symbol-cache work, the per-array $MUTATORS cache, the pre-created Map/Set methods — all kept exactly as the base has them.

Validation

• pnpm test — kernel 175 / mill 52 pass
• pnpm run typecheck — clean
• pnpm lint — clean
• pnpm format — clean (no further reformatting needed)
• pnpm run test:validate — clean

https://claude.ai/code/session_01VDVFSh8xJqvYp61dZQ8q4o

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Generated by Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (copilot/reduce-kernel-allocations@08a1f25). Learn more about missing BASE report.

Additional details and impacted files

@@                         Coverage Diff                          @@
##             copilot/reduce-kernel-allocations      #81   +/-   ##
====================================================================
  Coverage                                     ?   99.46%           
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  Files                                        ?       31           
  Lines                                        ?     1317           
  Branches                                     ?      260           
====================================================================
  Hits                                         ?     1310           
  Misses                                       ?        2           
  Partials                                     ?        5           

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[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

This PR removes newly introduced as any casts by routing intrusive symbol-cache access through the existing ReactiveTagged type, and applies formatting-only fixes (JSON indentation + line wrapping) to reduce churn.

Changes:

• Replace as any access to [$PROXY] / [$MUTATORS] with ReactiveTagged-typed access and extend ReactiveTagged to include [$MUTATORS]?.
• Reformat perf-stats.ts to match the formatter’s wrapping for long stats(...) calls.
• Revert packages/js-krauset/package.json to consistent 2-space indentation.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/kernel/src/read.ts	Removes as any from $MUTATORS access by using ReactiveTagged.
packages/kernel/src/core.ts	Extends ReactiveTagged to include optional [$MUTATORS] for type-safe symbol access.
packages/kernel/src/collections.ts	Removes as any from $PROXY intrusive cache reads via ReactiveTagged.
packages/js-krauset/perf-stats.ts	Wraps long stats(...) calls to match formatter output and avoid future reformat churn.
packages/js-krauset/package.json	Restores workspace-consistent 2-space JSON indentation.

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