fix(reactivity): update iterator to check for completion instead of value presence

[yangdan8]

…alue presence

Summary by CodeRabbit

• Bug Fixes
  • Fixed iteration behavior where falsy values (0, '', false) were not wrapped, which could lead to missed reactivity updates. Iteration now wraps all non-final results for consistent behavior, with no change to completed iterations.
  • Improves stability when consuming iterators in templates, computed values, and watchers. No public API changes.

[coderabbitai]

Walkthrough

Iterator wrapper in arrayInstrumentations now wraps values based on the iterator’s completion state: it applies wrapValue when result.done is false, covering falsy values; it skips wrapping when done is true. No public API or exported signatures changed.

Changes

Cohort / File(s)	Change Summary
Iterator wrapping logic packages/reactivity/src/arrayInstrumentations.ts	Changed condition from checking result.value to checking !result.done so wrapValue runs for all non-final iterator results, including falsy values; no wrapping on done results. No public API changes.

Sequence Diagram(s)

sequenceDiagram
  participant User
  participant ReactiveArray
  participant Iterator
  participant wrapValue

  User->>ReactiveArray: for...of / iteration
  ReactiveArray->>Iterator: next()
  loop Until done
    Iterator-->>ReactiveArray: { value, done: false }
    ReactiveArray->>wrapValue: wrap(value)
    wrapValue-->>ReactiveArray: wrappedValue
    ReactiveArray-->>User: wrappedValue
    ReactiveArray->>Iterator: next()
  end
  Iterator-->>ReactiveArray: { value, done: true }
  ReactiveArray-->>User: stop iteration (no wrapping)

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Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~15 minutes

Poem

I hop through loops with careful care,
Wrapping each nibble of value there—
Falsy or shiny, they all get a coat,
Until “done” whispers its final note.
Carrots compiled, I thump with glee,
Iterations neat as a clover leaf.

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📥 Commits

Reviewing files that changed from the base of the PR and between c875019 and 8354e25.

📒 Files selected for processing (1)

• packages/reactivity/src/arrayInstrumentations.ts (1 hunks)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (3)

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🔇 Additional comments (1)

packages/reactivity/src/arrayInstrumentations.ts (1)

218-221: Correct fix: check completion (done) instead of value truthiness.

This aligns iterator wrapping with the iterator protocol, ensuring falsy values (0, '', false) are handled correctly. No behavioral regressions expected for arrays; done-true results remain unwrapped.

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