chore(dev): add release script

.Rbuildignore

@@ -2,5 +2,6 @@
 ^.vscode
 ^LICENSE\.md$
 ^nix
+^release.sh
 ^shell.nix$
 ^tmp

README.md

@@ -106,6 +106,21 @@ my_data <- jsonlite::fromJSON(response$parse(encoding = "UTF-8"))
 print(my_data)
 ```
 
+## Releasing
+
+Make sure that your `main` branch is up to date:
+
+```sh
+git checkout main
+git pull
+```
+
+Then, run the release script with new version information:
+
+```sh
+./release.sh -n <X.Y.Z>
+```
+
 ## License
 
 This work is licensed under MIT license. See [LICENSE](./LICENSE.md).

release.sh

@@ -0,0 +1,91 @@
+#!/usr/bin/env bash
+
+## Stop on errors:
+set -eo pipefail
+
+## Helper function to print log messages.
+_log() {
+  echo "[RELEASE LOG]" "${@}"
+}
+
+## Helper function to print errors.
+_error() {
+  echo 1>&2 "[RELEASE ERROR]" "${@}"
+}
+
+## Helper function to print usage.
+_usage() {
+  echo "Usage: $0 [-h] -n <VERSION>"
+}
+
+## Declare variables:
+_version=""
+
+## Parse command line arguments:
+while getopts "n:h" o; do
+  case "${o}" in
+  n)
+    _version="${OPTARG}"
+    ;;
+  h)
+    _usage
+    exit 0
+    ;;
+  *)
+    _usage 1>&2
+    exit 1
+    ;;
+  esac
+done
+shift $((OPTIND - 1))
+
+_log "Checking variables..."
+if [ -z "${_version}" ]; then
+  _usage 1>&2
+  exit 1
+else
+  _log "Version is \"${_version}\". Proceeding..."
+fi
+
+_log "Checking git repository state..."
+if [[ -z "$(git status --porcelain)" ]]; then
+  _log "Git repository is clean. Proceeding..."
+else
+  _error "Git repository is not clean. Aborting..."
+  exit 1
+fi
+
+_log "Updating application version..."
+sed -i -E "s/^Version:([ ]+).*/Version:\\1${_version}/g" DESCRIPTION
+
+_log "Generating changelog..."
+git-chglog --output NEWS.md --next-tag "${_version}"
+
+_log "Staging changes..."
+git add NEWS.md DESCRIPTION
+
+_log "Committing changes..."
+git commit -m "chore(release): ${_version}"
+
+_log "Tagging version..."
+git tag -a -m "Release ${_version}" "${_version}"
+
+_log "Pushing changes to remote..."
+git push --follow-tags origin main
+
+_log "Creating the release..."
+gh release create "${_version}" --title "${_version}" --generate-notes
+
+_log "Updating application version for development..."
+sed -i -E "s/^Version:([ ]+).*/Version:\\1${_version}.9000/g" DESCRIPTION
+
+_log "Staging changes..."
+git add DESCRIPTION
+
+_log "Committing changes..."
+git commit -m "chore: bump development version to ${_version}.9000"
+
+_log "Pushing changes to remote..."
+git push
+
+_log "Finished!"