howto use a mojave vm vbox on a mac

1. via apple store, download mojave installer

2. sudo gem install macinbox

3. sudo macinbox -n gitlab-runner-1 --disk 50G --memory 8192 --cpu 8 --no-hidpi --short videolanci --full videolanci --password videolanci --verbose --box-format virtualbox

4. in virtualbox ui, import the machine from .vagrant.d/boxes/gitlab-runner-1/10.14.4/virtualbox/box.ovf

5. boot the machine

6. DO NOT (2020-01) install xcode cli tools

touch /tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress;
PROD=$(softwareupdate -l |
  grep "\*.*Command Line" |
  head -n 1 | awk -F"*" '{print $2}' |
  sed -e 's/^ *//' |
  tr -d '\n')
softwareupdate -i "$PROD" --verbose
rm /tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress

7. install xcode from appstore

xcode-select -s /Applications/Xcode.app/Contents/Developer/

 in xcode, go window - simulators - install ios 12, 13, tvos 12, 13 11

8. fetch the tools-osx.sh from http://thre.sh/stuff/tools-osx.sh to install VLC extras/tools to speed up compilation

9. chmod +x ./tools-osx.sh && ./tools-osx.sh

10. install jdk from https://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html 8u202 works

11. install python3 from python.org

12. install nasm from nasm.us > 2.14

13. install gitlab-runner, register as shell 

12. in vbox, use "macosx 64bit" as a vm type

13. in vbox, set cores == 4 for a vm

14. for gitlab-runner, specify disable_snapshots = false for one time to create
     a snapshot, run a job, then change to true - so gitlab runner will create
     a VM from a snapshot that is already there and will destroy the VM afterwards

15. When you need to update a VM, delete snapshots, run the VM image, update stuff, stop the VM and re-do the 14. disable_snaphots dance.