css_cache.ts

Cached extraction result for a single file. Uses null instead of empty arrays to avoid allocation overhead.

CSS cache version. Bump when any of these change: - CachedExtraction schema - extract_css_classes_with_locations() logic or output - ExtractionDiagnostic or SourceLocation structure

v1: Initial version with classes and diagnostics v2: Use null instead of empty arrays, add explicit_classes, elements, css_variables. v3: Add explicit_elements, explicit_variables for @fuz-elements/@fuz-variables comments. v4: Filter incomplete CSS variables in dynamic templates (e.g., var(--prefix_{expr})). v5: Remove css_variables and explicit_variables (now detected via simple regex scan). v6: Re-add explicit_variables for @fuz-variables comments (regex scan misses dynamic templates).

Default cache directory relative to project root.

Deletes a cached extraction file. Silently succeeds if the file doesn't exist.

Converts a cached extraction back to the runtime format. Preserves null semantics (null = empty).

Computes the cache file path for a source file. Cache structure mirrors source tree: src/lib/Foo.svelte → .fuz/cache/css/src/lib/Foo.svelte.json

Computes cache path for a file, handling both internal and external paths. Internal files use relative paths mirroring source tree. External files (outside project root) use hashed absolute paths in _external/.

Loads a cached extraction result from disk. Returns null if the cache is missing, corrupted, or has a version mismatch. This makes the cache self-healing: any error triggers re-extraction.

Saves an extraction result to the cache. Uses atomic write (temp file + rename) for crash safety. Normalizes empty collections to null to avoid allocation overhead on load.