PoC: BoxStylerWrapper for variant-aware resolution

[tilucasoli]

Summary

This is a Proof of Concept that changes the way a Styler is resolved.

Problem

Currently, variants live in a separate list inside the Styler. During resolution, they are merged only among themselves and applied at the end, after all other properties. This means context variants (like useToken) don't participate at the same level as regular properties — tokens work with reference values before the real resolved ones are available.

Approach

BoxStylerWrapper introduces an intermediate resolution layer that:

• Holds a list of BoxStyler layers independently (wrapping instead of merging)
• Resolves variants per layer before merging layers together
• Resolves all token references to concrete values

This guarantees that context variants like useToken are resolved at the same time as other properties, ensuring tokens work with actual resolved values rather than references.

Changes

• BoxStylerWrapper — new class in specs/box/ that wraps a list of BoxStyler and resolves them into a single BoxStyler with concrete values
• useToken — new method on VariantStyleMixin that resolves a token and passes the concrete value to a builder
• mergeActiveVariants — changed from @visibleForTesting to @internal for package-level access
• theme_tokens.dart — updated example demonstrating the wrapper + useToken pattern

Test plan

• Validate that tokens resolve correctly through BoxStylerWrapper.resolve()
• Validate that context variants are applied per layer before merging
• Validate that useToken resolves token values eagerly

🤖 Generated with Claude Code

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Project	Deployment	Actions	Updated (UTC)
mix-docs	Ready	Preview, Comment	Apr 7, 2026 3:22am