message: Remove printer's assertion
diff: @@ -17,7 +17,6 @@ async function runChildCommand(
  ): Promise<void> {
  try {
  await fn();
  - throw new Error('Expected a printer');
  } catch (err) {
  if (err instanceof DiagnosticsPrinter) {
  // If the command raises diagnostics, it is safe to throw the printer.
  