Ubuntu 18.04 Vagrantfile with RStudio Desktop installed and arbitrary version of R (via r-builds). user/pass is `vagrant:vagrant`

Vagrantfile

# -*- mode: ruby -*-
# vi: set ft=ruby :

# All Vagrant configuration is done below. The "2" in Vagrant.configure
# configures the configuration version (we support older styles for
# backwards compatibility). Please don't change it unless you know what
# you're doing.
Vagrant.configure("2") do |config|
  # The most common configuration options are documented and commented below.
  # For a complete reference, please see the online documentation at
  # https://docs.vagrantup.com.

  # Every Vagrant development environment requires a box. You can search for
  # boxes at https://vagrantcloud.com/search.
  config.vm.box = "bento/ubuntu-18.04"

  # Disable automatic box update checking. If you disable this, then
  # boxes will only be checked for updates when the user runs
  # `vagrant box outdated`. This is not recommended.
  # config.vm.box_check_update = false

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine. In the example below,
  # accessing "localhost:8080" will access port 80 on the guest machine.
  # NOTE: This will enable public access to the opened port
  # config.vm.network "forwarded_port", guest: 80, host: 8080

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine and only allow access
  # via 127.0.0.1 to disable public access
  # config.vm.network "forwarded_port", guest: 80, host: 8080, host_ip: "127.0.0.1"

  # Create a private network, which allows host-only access to the machine
  # using a specific IP.
  # config.vm.network "private_network", ip: "192.168.33.10"

  # Create a public network, which generally matched to bridged network.
  # Bridged networks make the machine appear as another physical device on
  # your network.
  # config.vm.network "public_network"

  # Share an additional folder to the guest VM. The first argument is
  # the path on the host to the actual folder. The second argument is
  # the path on the guest to mount the folder. And the optional third
  # argument is a set of non-required options.
  # config.vm.synced_folder "../data", "/vagrant_data"

  # Provider-specific configuration so you can fine-tune various
  # backing providers for Vagrant. These expose provider-specific options.
  # Example for VirtualBox:
  #
   config.vm.provider "virtualbox" do |vb|
  #   # Display the VirtualBox GUI when booting the machine
     vb.gui = true
  #
  #   # Customize the amount of memory on the VM:
     vb.memory = "1800"
   end
  #
  # View the documentation for the provider you are using for more
  # information on available options.

  # Enable provisioning with a shell script. Additional provisioners such as
  # Puppet, Chef, Ansible, Salt, and Docker are also available. Please see the
  # documentation for more information about their specific syntax and use.
  config.vm.provision "shell", inline: <<-SHELL
    apt-get update

    # Fix some issue in debconf that's preventing tasksel from working ATM
    apt-get install -yq aptitude
    aptitude reinstall debconf

    # Install a Linux GUI (Gnome)
    #sudo DEBIAN_FRONTEND=noninteractive apt install -yq gnome-session gdm3 gdebi-core
    echo "Installing Ubuntu desktop. This will take a long time..."
    sudo DEBIAN_FRONTEND=noninteractive tasksel install ubuntu-desktop
    echo "Done installing desktop"

    # Install RStudio Desktop
    sudo apt-get install -yq gdebi
    wget https://download1.rstudio.org/desktop/bionic/amd64/rstudio-1.2.1578-amd64.deb
    sudo gdebi -n rstudio-1.2.1578-amd64.deb

    # Install R
    R_VERSION=3.5.3
    wget https://cdn.rstudio.com/r/ubuntu-1804/pkgs/r-${R_VERSION}_1_amd64.deb
    sudo gdebi -n r-${R_VERSION}_1_amd64.deb
    sudo ln -fs /opt/R/${R_VERSION}/bin/R /usr/local/bin/R
    sudo ln -fs /opt/R/${R_VERSION}/bin/Rscript /usr/local/bin/Rscript
    # Obtained from testShinyExamples:::rspm_apt_get() via
    # https://github.com/rstudio/testShinyExamples
    sudo apt-get update && sudo apt-get install -y gdal-bin git libcairo2-dev libcurl4-openssl-dev libgdal-dev libgeos-dev libglpk-dev libgmp3-dev libicu-dev libpng-dev libproj-dev libssh2-1-dev libssl-dev libudunits2-dev libxml2-dev make pandoc zlib1g-dev
  SHELL
end