Arch Linux: make update-aur.sh easier to use: Dockerify

update-aur.sh sucks to use for me because it requires an Arch Linux
virtual machine. Simplify usage by creating an Arch Linux-based Docker
image and running part of the update-aur.sh script inside a container.

Author: strager

dist/arch/Dockerfile

@@ -0,0 +1,27 @@
+# Copyright (C) 2020  Matthew "strager" Glazar
+# See end of file for extended copyright information.
+
+FROM archlinux:base
+
+RUN pacman --sync --refresh --noconfirm binutils pacman-contrib
+
+RUN useradd --create-home --shell /bin/sh qljs-builder
+USER qljs-builder
+
+# quick-lint-js finds bugs in JavaScript programs.
+# Copyright (C) 2020  Matthew "strager" Glazar
+#
+# This file is part of quick-lint-js.
+#
+# quick-lint-js is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# quick-lint-js is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with quick-lint-js.  If not, see <https://www.gnu.org/licenses/>.

dist/arch/README.md

@@ -26,3 +26,18 @@ following commands:
 To install the built package, run the following command:
 
     $ sudo pacman -U ./quick-lint-js-*.pkg.tar.zst
+
+## Docker image
+
+For convenience, we have a Docker image based on Arch Linux.
+
+### Updating the Docker image
+
+Pick a version number for the new Docker image (e.g. `v3`), then run the
+following commands:
+
+    $ docker build --tag ghcr.io/quick-lint/quick-lint-js-dist-arch:VERSION_NUMBER_HERE dist/arch/
+    $ docker login ghcr.io -u YOUR_GITHUB_USER_NAME_HERE
+    $ docker push ghcr.io/quick-lint/quick-lint-js-dist-arch:VERSION_NUMBER_HERE
+
+Then, change the container tag in `update-aur.sh` refer to your new version.

dist/arch/update-aur.sh

@@ -6,19 +6,58 @@
 set -e
 set -u
 
-if [ "${#}" -ne 1 ]; then
-  printf 'usage: %s /path/to/quick-lint-js-aur\n' "${0}" >&2
+here="$(cd "$(dirname "${0}")" && pwd)"
+
+print_usage() {
+  printf 'usage: %s [--docker] /path/to/quick-lint-js-aur\n' "${0}"
+}
+
+docker=0
+qljsaur=
+
+docker_image=ghcr.io/quick-lint/quick-lint-js-dist-arch:v1
+
+while [ "${#}" -ne 0 ]; do
+  case "${1}" in
+    --docker) docker=1 ;;
+    -*)
+      printf 'error: invalid option: %s\n' "${1}"
+      print_usage >&2
+      exit 1
+      ;;
+    *) qljsaur="$(cd "${1}" && pwd)" ;;
+  esac
+  shift
+done
+
+if [ -z "${qljsaur}" ]; then
+  print_usage >&2
   exit 1
 fi
 
-qljsaur="${1}"
-here="$(cd "$(dirname "${0}")" && pwd)"
-
 cd "${qljsaur}"
-
 cp "${here}/PKGBUILD-release" PKGBUILD
-updpkgsums PKGBUILD
-makepkg --printsrcinfo PKGBUILD >.SRCINFO
+
+script="
+  updpkgsums PKGBUILD
+  makepkg --printsrcinfo PKGBUILD >.SRCINFO
+"
+if [ "${docker}" -eq 1 ]; then
+  docker run -t --mount type=bind,source="${qljsaur}",destination=/qljs-aur "${docker_image}" sh -c "
+    set -e
+    set -u
+    cd /qljs-aur
+    ${script}
+  "
+else
+  if ! command -v updpkgsums >/dev/null; then
+    printf "warning: updpkgsums doesn't seem to be installed. Consider using --docker\n" >&2
+  fi
+  if ! command -v makepkg >/dev/null; then
+    printf "warning: makepkg doesn't seem to be installed. Consider using --docker\n" >&2
+  fi
+  eval "${script}"
+fi
 
 git add PKGBUILD .SRCINFO
 printf '\nChanges staged. Please commit and push.\n' >&2

docs/RELEASE.md

@@ -55,8 +55,7 @@ Follow the following steps to release a new version of quick-lint-js:
 12. Update Arch Linux user repositories (AUR):
     1. Clone ssh://[email protected]/quick-lint-js with Git.
     2. Update README to point to the tag's commit.
-    3. On an Arch Linux machine, run `dist/arch/update-aur.sh
-       /path/to/quick-lint-js-aur-clone`.
+    3. Run `dist/arch/update-aur.sh --docker /path/to/quick-lint-js-aur-clone`.
     4. Commit all files with message "Update quick-lint-js to version
        VERSION_NUMBER".
     5. On an Arch Linux machine, cd into the quick-lint-js AUR clone and run