src/vs/editor/contrib/folding/syntaxRangeProvider.ts/SyntaxRangeProvider/compute
class SyntaxRangeProvider:	compute(cancellationToken: CancellationToken): Promise<FoldingRegions | null> {
		return collectSyntaxRanges(this.providers, this.editorModel, cancellationToken).then(ranges => {
			if (ranges) {
				let res = sanitizeRanges(ranges, this.limit);
				return res;
			}
			return null;
		});
	}