Extensions - Language Features: Implement semantic highlighting #3370
Description
The extension host provides some APIs for semantic highlighting:
$registerDocumentSemanticTokensProvider(handle: number, selector: IDocumentFilterDto[], legend: modes.SemanticTokensLegend, eventHandle: number | undefined): void;
$emitDocumentSemanticTokensEvent(eventHandle: number): void;
$registerDocumentRangeSemanticTokensProvider(handle: number, selector: IDocumentFilterDto[], legend: modes.SemanticTokensLegend): void;
and
$provideDocumentSemanticTokens(handle: number, resource: UriComponents, previousResultId: number, token: CancellationToken): Promise<VSBuffer | null>;
$releaseDocumentSemanticTokens(handle: number, semanticColoringResultId: number): void;
$provideDocumentRangeSemanticTokens(handle: number, resource: UriComponents, range: IRange, token: CancellationToken): Promise<VSBuffer | null>;
We need to wire these APIs up, and integrate them into our language feature / syntax highlighting pipeline, to support languages that use these rich semantic highlights.
Some extensions to test with semantic token support: