Error installing Laravel 5.2 on forge

Question

I am trying to resolve this error and look for an answer everywhere. I checked and they are all included in the ini file and this gives me an error.

Downloading composer repositories with information about a package Installing dependencies from a lock file Your requirements cannot be resolved to an installed set of packages.

Problem 1 - Request to install saber / xml dev-master → execute saber / xml [dev-master]. - saber / xml dev-master requires ext-dom * → the requested php extension dom is missing on your system.

To enable extensions, verify that they are enabled in those .ini files:
    - /etc/php/7.0/cli/php.ini
    - /etc/php/7.0/cli/conf.d/10-mysqlnd.ini
    - /etc/php/7.0/cli/conf.d/10-opcache.ini
    - /etc/php/7.0/cli/conf.d/10-pdo.ini
    - /etc/php/7.0/cli/conf.d/20-calendar.ini
    - /etc/php/7.0/cli/conf.d/20-ctype.ini
    - /etc/php/7.0/cli/conf.d/20-curl.ini
    - /etc/php/7.0/cli/conf.d/20-exif.ini
    - /etc/php/7.0/cli/conf.d/20-fileinfo.ini
    - /etc/php/7.0/cli/conf.d/20-ftp.ini
    - /etc/php/7.0/cli/conf.d/20-gd.ini
    - /etc/php/7.0/cli/conf.d/20-gettext.ini
    - /etc/php/7.0/cli/conf.d/20-iconv.ini
    - /etc/php/7.0/cli/conf.d/20-igbinary.ini
    - /etc/php/7.0/cli/conf.d/20-imap.ini
    - /etc/php/7.0/cli/conf.d/20-json.ini
    - /etc/php/7.0/cli/conf.d/20-mbstring.ini
    - /etc/php/7.0/cli/conf.d/20-mcrypt.ini
    - /etc/php/7.0/cli/conf.d/20-mysqli.ini
    - /etc/php/7.0/cli/conf.d/20-pdo_mysql.ini
    - /etc/php/7.0/cli/conf.d/20-pdo_pgsql.ini
    - /etc/php/7.0/cli/conf.d/20-pdo_sqlite.ini
    - /etc/php/7.0/cli/conf.d/20-pgsql.ini
    - /etc/php/7.0/cli/conf.d/20-phar.ini
    - /etc/php/7.0/cli/conf.d/20-posix.ini
    - /etc/php/7.0/cli/conf.d/20-readline.ini
    - /etc/php/7.0/cli/conf.d/20-shmop.ini
    - /etc/php/7.0/cli/conf.d/20-sockets.ini
    - /etc/php/7.0/cli/conf.d/20-sqlite3.ini
    - /etc/php/7.0/cli/conf.d/20-sysvmsg.ini
    - /etc/php/7.0/cli/conf.d/20-sysvsem.ini
    - /etc/php/7.0/cli/conf.d/20-sysvshm.ini
    - /etc/php/7.0/cli/conf.d/20-tokenizer.ini
    - /etc/php/7.0/cli/conf.d/20-zlib.ini
    - /etc/php/7.0/cli/conf.d/25-memcached.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.

Answer 1

ubuntu 16.04, php7. , : :

      sudo apt-get update

:

      sudo apt-get install mcrypt php7.0-mcrypt

:

      sudo apt-get upgrade

php-mbstring:

     sudo apt-get install php-mbstring

phpunit, :

     sudo apt-get install phpunit

.