No graceful error? :(

cross-spawn.js

    .then(([{cmd, args}, dependencies]) => {
      process.chdir(dir);
      return new Promise((resolve, reject) => {
        const spinner = ora(chalk.dim('Installing dependencies. This may take a while...')).start();
        const stdio = verbose ? 'inherit' : [process.stdin, 'ignore', 'ignore'];
        const child = spawn(cmd, args.concat(dependencies), { stdio });
        child.on('error', err => reject(err));
        child.on('exit', code => {
          if (code > 0) {
            spinner.text = 'Installation failed!';
            spinner.fail();
            return;
          }
          spinner.text = 'Installation complete!';
          spinner.succeed();
          resolve();
        })
      });
    });

execa.js

    .then(([{cmd, args}, dependencies]) => {
      process.chdir(dir);
      const spinner = ora(chalk.dim('Installing dependencies. This may take a while...')).start();
      const child = spawn(cmd, args.concat(dependencies))
        // We have to do a nested catch, so we don't lose
        // reference to the `spinner`.
        .catch(err => {
          // Just forward, we only want to stop the spinner.
          spinner.text = 'Installation failed!';
          spinner.fail();
          return Promise.reject(err);
        });
      if(verbose) {
        child.stdout.pipe(process.stdout);
      }
      return Promise.all([spinner, child]);
    })
    .then(([spinner, result]) => {
      spinner.text = 'Installation complete!';
      spinner.succeed();
      return result;
    });