message: cli: skip testinging of repo test --since matches nothing
diff: @@ -101,6 +101,12 @@ export async function command(opts: OptionValues, cmd: Command): Promise<void> {
  pkg => pkg.allLocalDependents.keys(),
  ),
  );
  +
  + if (packageNames.length === 0) {
  + console.log(`No packages changed since ${opts.since}`);
  + return;
  + }
  +
  args.push('--selectProjects', ...packageNames);
  }
  