extensions/typescript-language-features/src/languageFeatures/fileConfigurationManager.ts/FileConfigurationManager/ensureConfigurationForDocument
class FileConfigurationManager:	public async ensureConfigurationForDocument(
		document: vscode.TextDocument,
		token: vscode.CancellationToken
	): Promise<void> {
		const formattingOptions = this.getFormattingOptions(document);
		if (formattingOptions) {
			return this.ensureConfigurationOptions(document, formattingOptions, token);
		}
	}