feat(builder): Merge OpaqueRef and Cell

[seefeldb]

Merge OpaqueRef and Cell Implementation

Summary

This PR completes a major architectural refactoring that merges OpaqueRef and Cell into a unified implementation. Previously, these were separate concepts with duplicated functionality. Now, OpaqueRef is implemented as a proxy wrapper around Cell, eliminating code duplication and simplifying the mental model for working with reactive values.

Key Changes

Core Architecture

• Unified Cell Implementation: Merged StreamCell into RegularCell (renamed to CellImpl), creating a single cell type that handles both regular and stream behavior
• OpaqueRef <=> Cell Relationship: OpaqueRef is now a proxy wrapper around Cell instances, rather than a separate implementation
• Runtime-Aware Cells: Cells now receive runtime context at construction time through a default frame, enabling proper ID generation and lifecycle management

Cell Construction & Linking

• Optional Links: Cell constructor now accepts an optional link parameter, allowing cells to be created without an immediate link
• .for() Method: New method to set a cause/link for cells that don't have one yet, enabling lazy link creation
• Frame-Based Runtime Access: Builder functions access runtime, space and current transaction via frame

Cell Kinds System

• CellKind Enum: Introduced standardized cell kinds: "cell", "opaque", "stream", "comparable", "readonly", "writeonly"
• Type-Safe Branding: Updated BrandedCell<T, Kind> to use CellKind for better type safety

Cleanup & Deprecation

• Removed toOpaqueRef(): No longer needed since all cells are now also OpaqueRefs
• Deprecated Methods: Removed setDefault(), setPreExisting(), and other legacy methods that are no longer needed
• Removed Shadow Refs: Disabled unsafe closure capture behavior and removed related tests
• Better Error Messages: Improved error messages for closed-over variables in lift/derive

API Changes

• cell() Function: Simplified signature - cell<T>(defaultValue?, schema?)
• stream() Function: Updated to stream<T>(schema?) for consistency
• Handler Returns: Handler return values automatically get .for() called with appropriate context

Migration Impact

Breaking Changes

• toOpaqueRef() removed - cells are already opaque refs
• setDefault() deprecated - use constructor parameter instead
• setPreExisting() removed - use .for() instead
• Shadow refs (closure capture) no longer supported

Non-Breaking Changes

• Most existing code continues to work due to proxy implementation
• Type signatures updated but generally backward compatible
• Patterns needed updates but follow clearer patterns now

Testing

• All existing tests updated and passing
• New test suite for optional links: cell-optional-link.test.ts (445 lines)
• Pattern integration tests updated and verified
• Removed obsolete tests for deprecated features

Benefits

1. Simpler Mental Model: One unified concept instead of two separate ones
2. Less Code Duplication: Shared implementation reduces maintenance burden
3. Better Type Safety: CellKind system provides stronger guarantees
4. Cleaner API: Removed confusing legacy methods
5. Improved Performance: Single implementation path is more optimizable
6. Better Debugging: Clearer error messages and simpler call stacks

---

Summary by cubic

Merged OpaqueRef and Cell into a single, Cell-backed implementation with runtime-aware construction. This simplifies the API, enables creating cells without links, and clarifies stream behavior.

• Refactors

  • OpaqueRef is now a proxy over Cell; one unified CellImpl for regular and stream cells.
  • Stream handling uses kind="stream"; stream(schema?) replaces $stream markers.
  • Cells can start without a full link; .for(cause, allowIfSet?) associates a cause and creates links lazily. Siblings share a CauseContainer.
  • Cells capture the creation frame (runtime/space/tx) for ID generation and lifecycle; Runtime sets a default frame.
  • Builder functions and built-ins use frame-based runtime; opaqueRef() always returns a Cell-backed ref; raw remains unchanged.
  • Introduced CellKind and BrandedCell<T, Kind> for stronger typing.

• Migration

  • Use schema defaults instead of setDefault; pass defaults via schema or opaqueRef(value, schema).
  • Removed toOpaqueRef(); cells are already opaque refs. Rename isQueryResult* to isCellResult*.
  • Removed setPreExisting(); use .for(cause[, true]) to suggest a cause, or omit the flag to enforce and throw if already set.
  • stream(schema?) replaces stream(initialValue); initial value via schema.default.
  • Removed shadow refs (closure capture).
  • Replace isOpaqueRef checks with isCell where needed.

^{Written for commit 9785fc6. Summary will update automatically on new commits.}

[cubic-dev-ai]

7 issues found across 48 files

Prompt for AI agents (all 7 issues)

Understand the root cause of the following 7 issues and fix them.


<file name="packages/generated-patterns/integration/patterns/counter-delayed-compute.pattern.ts">

<violation number="1" location="packages/generated-patterns/integration/patterns/counter-delayed-compute.pattern.ts:25">
Using derive here returns a computed value but never drains the pending queue or writes the new total back to the underlying cell. Because derive’s callback only receives plain values, the increments remain queued and rawValue never advances, breaking the counter’s persistence.</violation>
</file>

<file name="packages/runner/src/builder/types.ts">

<violation number="1" location="packages/runner/src/builder/types.ts:109">
Rename this interface back to IOpaquable so the module augmentation still merges into the upstream interface instead of defining a brand-new IOxpaquable type.</violation>
</file>

<file name="packages/runner/test/wish.test.ts">

<violation number="1" location="packages/runner/test/wish.test.ts:39">
Remove `.only` so the full test suite runs. Leaving this focused spec in committed code will cause the rest of the suite to be skipped during CI.</violation>
</file>

<file name="packages/runner/src/builder/opaque-ref.ts">

<violation number="1" location="packages/runner/src/builder/opaque-ref.ts:26">
`opaqueRef` now throws whenever the current frame lacks a runtime, but builder code (e.g. `recipe()`) still pushes frames without a runtime before calling `opaqueRef`, so recipe construction now crashes instead of producing a ref.</violation>
</file>

<file name="packages/api/index.ts">

<violation number="1" location="packages/api/index.ts:44">
`[CELL_BRAND]` should stay typed as `Kind`; unioning with `string` collapses the brand to `string` and destroys the compile-time differentiation between cell kinds.</violation>
</file>

<file name="packages/runner/src/builder/recipe.ts">

<violation number="1" location="packages/runner/src/builder/recipe.ts:292">
Falling back to `true` here drops the default-derived argument schema, so recipes without explicit schemas lose the structure/default metadata that downstream tooling relies on. Please restore the schema derivation instead of returning `true`.</violation>
</file>

<file name="packages/runner/src/runtime.ts">

<violation number="1" location="packages/runner/src/runtime.ts:422">
Always pass the stored default frame to popFrame so disposal removes the correct frame and surfaces any mismatch.</violation>
</file>

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