PreviewUpdateService

How to read this API

These are TypeScript APIs compiled into SnapTeX; a .tex project cannot load them at runtime.

• function name(...) is a helper that your rule imports and calls.
• apply(...), render(...), extract(...), and collect(...) are callbacks that your rule implements and SnapTeX calls.
• renderer.name(...), context.name(...), input.name(...), and deps.name(...) are methods SnapTeX supplies to callbacks; do not import or construct them.
• service.name(...) is an instance method called after your host or test constructs PreviewUpdateService.

Register extension declarations through SNAP_TEX_RULES in src/rules.ts. See Source API Scope for imports, value ownership, output safety, rebuilds, and testing.

Coordinates document parsing and renderer state without depending on a VS Code or Web UI. Use it for end-to-end rule tests and host integration; use lower-level helpers only for isolated parser or formatter tests.

Constructor

new PreviewUpdateService<TUri>(
    fileProvider: IFileProvider<TUri>,
    registry: RuleRegistry = SNAP_TEX_RULES
)

Parameters

Parameter	Description
fileProvider	Host-neutral project file reader used for inputs, bibliography, images, and included files
registry	Registry under test; defaults to the built-in SNAP_TEX_RULES

Instance responsibilities

The service owns one LatexDocument and one SmartRenderer. It retains diff, numbering, citation, dependency, and lazy-render state across calls to render.

Useful methods include:

• render
• renderBlockByIndex
• resetState
• getDiagnostics
• getPreviewSyncData / getSourceSyncData
• isKnownFile
• getBibliographyKeys / getMacroNames

Call relationships

• Constructs: LatexDocument and SmartRenderer with the same registry.
• Used by: VS Code, Web/standalone hosts, and end-to-end tests.

file provider + registry -> PreviewUpdateService
                         -> LatexDocument + SmartRenderer
                         -> RenderPayload / lazy block HTML / sync data

const service = new PreviewUpdateService(
    new MemoryFileProvider(),
    SNAP_TEX_RULES
);

See also

• Call Relationships
• defineRuleRegistry