Add value mapping to modifier config

Extend ModifierConfig with valueMap and mapTarget fields so that modifier values can be declaratively mapped to different data attribute values. This is the smallest SPEC-033 feature and eliminates 2 existing postTransform uses.

claude/file-naming-convention-LJdwR View source

Criteria completion

Tracking started Apr 21 — check back for trends.

Relationships

ID:SPEC-033Status:accepted

Structure Slots and Declarative Flexibility

ID:WORK-112Status:done

Implement named slots with ordering for structure entries

Priority:highComplexity:moderateMilestone:v1.0.0

ID:WORK-115Status:ready

Migrate community package postTransform uses to declarative config

Priority:mediumComplexity:moderateMilestone:v1.0.0

claude/file-naming-convention-LJdwR current done

changeset-release/main done main done

Apr 21, 01:29 PMbbbb94c
Created (done)by bjornolofandersson
Apr 21, 01:17 PMf2b3512
Content editedby Claude
Add {ID}-{slug}.md filename convention + migrate filenames subcommand

Acceptance Criteria

ModifierConfig in packages/transform/src/types.ts has valueMap?: Record<string, string> and mapTarget?: string fields
The engine's modifier resolution in packages/transform/src/engine.ts applies valueMap before emitting data attributes — mapped values go to mapTarget (or the same attribute if mapTarget is not set)
Unmapped values pass through unchanged
mergeThemeConfig correctly merges valueMap overrides (theme replaces base valueMap per modifier)
Unit tests cover: basic mapping, unmapped passthrough, mapTarget redirection, merge behavior
TypeScript compiles cleanly across all packages
All existing tests pass

Approach

Add valueMap and mapTarget to ModifierConfig in packages/transform/src/types.ts
In the engine's modifier application logic, after resolving the raw value from meta tags, check for valueMap — if present, look up the value and replace it (or pass through if not found)
If mapTarget is set, emit the mapped value as a separate data attribute (e.g., data-checked) in addition to or instead of the original modifier attribute
Update mergeThemeConfig in packages/transform/src/merge.ts to handle valueMap (theme valueMap replaces base, not deep-merged)
Write tests validating the mapping behavior

References

SPEC-033 (Feature 2 — Value Mapping)