extensions/typescript-language-features/src/typeScriptServiceClientHost.ts/TypeScriptServiceClientHost/handles
class TypeScriptServiceClientHost:	public async handles(resource: vscode.Uri): Promise<boolean> {
		const provider = await this.findLanguage(resource);
		if (provider) {
			return true;
		}
		return this.client.bufferSyncSupport.handles(resource);
	}