Enable testing against MacOS in CI/CD!

This is pretty cool, I hope it works! 🤞 It uses the `macos` orb
provided by CircleCI, as documented here:
https://circleci.com/docs/using-macos

This commit also rewrites the older anchor style common steps into the
newer command syntax, which is more readable. The command syntax is
documented here:
https://circleci.com/docs/configuration-reference#commands

Installing pre-reqs on MacOS via `brew` was non-trivial. This is
mainly because of the `sed` command used in the `Makefile`. It isn't a
problem normally because it is only used for packaging, which is done
on Melpa

Relates to: vedang#98

.circleci/config.yml

@@ -1,47 +1,109 @@
 version: 2.1
 
-# Default actions to perform on each Emacs version
-default: &default-steps
-  steps:
-    - checkout
-    - run: apt-get update && apt-get install -y gcc make automake autoconf libpng-dev libz-dev libpoppler-glib-dev
-    - run: cask upgrade-cask || true
-    - run: emacs --version
-    - run: cask --version
-    - run: cask install
-    - run: make test
-
-# Enumerated list of Emacs versions
+orbs:
+  macos: circleci/macos@2
+
+commands:
+  install-ubuntu-prereqs:
+    steps:
+      - run:
+          name: Install base prereqs needed for running make commands
+          command: |
+            apt-get update --fix-missing -y && apt-get install -y make tzdata
+  install-pdf-tools-server:
+    steps:
+      - checkout
+      - run:
+          name: Install pdf-tools Server Pre-reqs and Compile epdfinfo
+          command: |
+            make autobuild
+      - run:
+          name: Upgrade Cask to the latest version
+          command: |
+            cask upgrade-cask || true
+      - run:
+          name: Confirm that Emacs is installed and on Path
+          command: |
+            emacs --version
+      - run:
+          name: Confirm that Cask is installed and on Path
+          command: |
+            cask --version
+      - run:
+          name: Install pdf-tools elisp pre-reqs
+          command: |
+            cask install
+      - run:
+          name: Run pdf-tools elisp tests
+          command: |
+            make test
+
+# Test various Emacs versions on Ubuntu
 jobs:
-  test-emacs-26:
+  test-on-emacs-26:
     docker:
       - image: silex/emacs:26-ci-cask
         entrypoint: bash
-    <<: *default-steps
+    steps:
+      - install-ubuntu-prereqs
+      - install-pdf-tools-server
 
-  test-emacs-27:
+  test-on-emacs-27:
     docker:
       - image: silex/emacs:27-ci-cask
         entrypoint: bash
-    <<: *default-steps
+    steps:
+      - install-ubuntu-prereqs
+      - install-pdf-tools-server
 
-  test-emacs-28:
+  test-on-emacs-28:
     docker:
       - image: silex/emacs:28-ci-cask
         entrypoint: bash
-    <<: *default-steps
+    steps:
+      - install-ubuntu-prereqs
+      - install-pdf-tools-server
 
-  test-emacs-master:
+  test-on-emacs-master:
     docker:
       - image: silex/emacs:master-ci-cask
         entrypoint: bash
-    <<: *default-steps
+    steps:
+      - install-ubuntu-prereqs
+      - install-pdf-tools-server
+
+  test-on-macos:
+    macos:
+      xcode: "14.1.0"
+    resource_class: medium
+    environment:
+      HOMEBREW_NO_AUTO_UPDATE: 1
+      HOMEBREW_NO_INSTALL_CLEANUP: 1
+    steps:
+      - run:
+          name: Install Emacs on MacOS
+          command: |
+            brew install --cask emacs
+      - run:
+          name: Install Cask on MacOS
+          command: |
+            git clone https://github.com/cask/cask ~/.cask
+      - run:
+          name: Install Brew prereqs
+          command: |
+            brew install gnu-sed
+      - run:
+          name: Add Cask and Gnu-SED to the Path
+          command: |
+            echo 'export PATH="$HOME"/.cask/bin:"$(brew --prefix)"/opt/gnu-sed/libexec/gnubin:"$PATH"' >> "$BASH_ENV"
+      - install-pdf-tools-server
 
 workflows:
   version: 2
   ci-test-matrix:
     jobs:
-      - test-emacs-26
-      - test-emacs-27
-      - test-emacs-28
-      - test-emacs-master
+      - test-on-emacs-26
+      - test-on-emacs-27
+      - test-on-emacs-28
+      - test-on-emacs-master
+      - test-on-macos

server/test/docker/templates/ubuntu-22.Dockerfile.in

@@ -2,4 +2,4 @@
 FROM ubuntu:jammy
 ARG DEBIAN_FRONTEND=noninteractive
 # Need to install make, tzdata here to avoid stupid prompts when running package install via autobuild
-RUN apt-get update -y && apt-get install -y make tzdata
+RUN apt-get update --fix-missing -y && apt-get install -y make tzdata