Fix the included Vagrantfile for running rspec tests

.github/CONTRIBUTING.md

@@ -34,6 +34,8 @@ No pull request template is provided on GitHub. The expected changes are often a
 
 ### Setup a development installation of Vagrant
 
+*A Vagrantfile is provided that should take care setting up a VM for running the rspec tests.* If you only need to run those tests and don't also want to run a development version of Vagrant from a host machine then it's recommended to use that.
+
 There are a few prerequisites for setting up a development environment with Vagrant. Ensure you have the following installed on your machine:
 
 * git

Vagrantfile

@@ -14,7 +14,12 @@ Vagrant.configure("2") do |config|
     end
   end
 
-  config.vm.provision "shell", inline: $shell
+  # We split apart `install_rvm` from `setup_tests` because rvm says to
+  # logout and log back in just after installing RVM.
+  # https://github.com/rvm/ubuntu_rvm#3-reboot
+  config.vm.provision "shell", path: "scripts/install_rvm"
+
+  config.vm.provision "shell", path: "scripts/setup_tests"
 
   config.push.define "www", strategy: "local-exec" do |push|
     push.script = "scripts/website_push_www.sh"
@@ -24,54 +29,3 @@ Vagrant.configure("2") do |config|
     push.script = "scripts/website_push_docs.sh"
   end
 end
-
-$shell = <<-'CONTENTS'
-export DEBIAN_FRONTEND=noninteractive
-MARKER_FILE="/usr/local/etc/vagrant_provision_marker"
-RUBY_VER_REQ=$(awk '$1 == "s.required_ruby_version" { print $4 }' /vagrant/vagrant.gemspec | tr -d '"')
-
-# Only provision once
-if [ -f "${MARKER_FILE}" ]; then
-  exit 0
-fi
-
-# Add ubuntu_rvm repo
-apt-add-repository -y ppa:rael-gc/rvm
-
-# Update apt
-apt-get update --quiet
-
-# Add vagrant user to sudo group:
-# ubuntu_rvm only adds users in group sudo to group rvm
-usermod -a -G sudo vagrant
-
-# Install basic dependencies and RVM
-apt-get install -qy build-essential bsdtar rvm
-
-# Import the mpapis public key to verify downloaded releases
-su -l -c 'gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3' vagrant
-
-# Install next-to-last Ruby that complies with Vagrant's version constraint
-RUBY_VER=$(su -l -c 'rvm list known' vagrant | tr '[]-' ' ' | awk "/^ ruby  ${RUBY_VER_REQ:0:1}\./ { print \$2 }" | sort -r | sed -n '2p')
-su -l -c "rvm install ${RUBY_VER}" vagrant
-su -l -c "rvm --default use ${RUBY_VER}" vagrant
-
-# Output the Ruby version (for sanity)
-su -l -c 'ruby --version' vagrant
-
-# Install Git
-apt-get install -qy git
-
-# Upgrade Rubygems
-su -l -c "rvm ${RUBY_VER} do gem update --system" vagrant
-
-# Prepare to run unit tests
-su -l -c 'cd /vagrant; bundle install' vagrant
-
-# Automatically move into the shared folder, but only add the command
-# if it's not already there.
-grep -q 'cd /vagrant' /home/vagrant/.bash_profile 2>/dev/null || echo 'cd /vagrant' >> /home/vagrant/.bash_profile
-
-# Touch the marker file so we don't do this again
-touch ${MARKER_FILE}
-CONTENTS

scripts/install_rvm

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+export DEBIAN_FRONTEND=noninteractive
+
+if ! rvm --version
+then
+  # https://github.com/rvm/ubuntu_rvm#install
+  apt-add-repository -y ppa:rael-gc/rvm &&
+    apt-get update -y &&
+    apt-get install -y rvm || {
+      echo 'Failed to install rvm' >&2
+      exit 1
+    }
+fi
+
+usermod -a -G rvm vagrant || {
+  echo 'Failed to add vagrant to the rvm group' >&2
+  exit 1
+}

scripts/setup_tests

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+
+rvm --version || {
+  echo 'rvm not installed' >&2
+  exit 1
+}
+
+# bsdtar is required for a small subset of the tests
+if ! bsdtar --version
+then
+  apt-get install -y bsdtar &&
+    bsdtar --version || {
+      echo 'Failed to install bsdtar' >&2
+      exit 1
+    }
+fi
+
+# Install next-to-last Ruby that complies with Vagrant's version
+# constraint
+RUBY_VER_REQ=$(
+  awk '
+    $1 == "s.required_ruby_version" { print $4 }
+  ' /vagrant/vagrant.gemspec |
+    tr -d '"')
+RUBY_VER=$(sudo -u vagrant -i rvm list known |
+             tr '[]-' ' ' |
+             awk "/^ ruby  ${RUBY_VER_REQ:0:1}\./ { print \$2 }" |
+             sort -r |
+             sed -n '2p')
+sudo -u vagrant -i rvm install "${RUBY_VER}"
+sudo -u vagrant -i rvm --default use "${RUBY_VER}"
+
+# Output the Ruby version (for sanity)
+sudo -u vagrant -i ruby --version
+
+# Upgrade Rubygems
+sudo -u vagrant -i rvm "${RUBY_VER}" do gem update --system
+
+# Prepare to run unit tests
+sudo -u vagrant -i bash -c 'cd /vagrant; bundle install'
+
+# Automatically move into the shared folder, but only add the command if
+# it's not already there.
+if ! grep -q 'cd /vagrant' /home/vagrant/.bash_profile
+then
+  cat <<EOF >> /home/vagrant/.bash_profile
+cd /vagrant
+EOF
+fi