/**
  * Update salts in the environment file.
  *
  * @param bool $force Whether or not to force update any existing values
  *
  * @return Collection
  */
 protected function update_salts($force = false)
 {
     return $this->salts->map(function ($salt) use($force) {
         list($key, $value) = $salt;
         if (!$force && $this->env->hasKey($key)) {
             WP_CLI::line("The '{$key}' already exists, skipping.");
             $salt['skipped'] = true;
             return $salt;
         }
         $this->env->set($key, $value, "'");
         return $salt;
     });
 }