feat: Reactivity System Improvements & Test Coverage

[treardon17]

Claude

This PR adds a CLAUDE.md file, and claude helped find and fix some defects, performance issues, and added map/set support.

Bug Fixes

Scheduler Error Recovery

Problem: If a scheduled task threw an error, the scheduler's SCHEDULER_ID was never reset, preventing all future tasks from being scheduled.

Solution: Added proper error handling with try/catch around individual tasks and a finally block to always reset the scheduler state:

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Code Improvements

Consolidated Type Detection

• Simplified Reactive.getStringType() to a clean implementation using isPlainObject():
• The isPlainObject check only proxies objects created via {} or Object.create(null). This naturally excludes problematic types (Promise, Date, WeakMap, WeakSet, RegExp, Error, ArrayBuffer, typed arrays, DOM nodes, class instances) because none of them have Object.prototype as their direct prototype.
• Updated JSDoc Import Paths
• Changed all documentation examples from 'madrone' to '@madronejs/core' to match the new package name.

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Test Coverage Added

New Test Files

File	Tests	Coverage
src/spec/util.spec.ts	11	applyClassMixins, getDefaultDescriptors
src/spec/global.spec.ts	30	Integration registry, toRaw, objectAccessed, lastAccessed

Extended Existing Tests

observer.spec.ts

• cache: false mode (recomputes every access)
• onGet hook (called on every value access)
• onImmediateChange hook (synchronous change notification)
• Writable computed with onSet hook
• Error cases for missing setters

reactive.spec.ts

• onDelete callback for property deletion
• onHas callback for in operator and Object.keys()
• Custom needsProxy function
• Symbol keys
• Frozen/sealed objects (non-configurable properties)
• Shallow reactivity (deep: false)
• Edge cases: null prototype objects, getters/setters, circular references

scheduler.spec.ts

• Error handling: continues processing after task throws
• Recovery: allows new tasks after errors
• Nested task error handling
• Multiple errors in same batch

Total: 295 tests (all passing)

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Performance Implications

1. Reduced Proxy Overhead: By not proxying class instances and native objects, there's less memory overhead and fewer proxy trap invocations for objects that don't need reactivity.
2. Simplified Type Detection: The consolidated isPlainObject check is a single prototype comparison instead of multiple instanceof checks, reducing the cost of type detection.
3. Robust Scheduler: Error handling prevents the scheduler from getting stuck, ensuring reactive updates continue even when individual handlers fail.

[bitencode]

Looks good to me - I looked at code changes and briefly scanned tests and doc changes. Don't have a good way to test this other then unit tests, so I'm assuming (a bit) that it's good. 😉
Give my regards and thanks to Claude for help with JSDoc, examples and unit tests 😂
Thank you - it does look safer and possibly more performant 👍