FP-1544: Annotate Lightweight Tags

.gitignore

@@ -3,6 +3,9 @@
 *.pyo
 __pycache__
 
+# Shell
+_git_annotate_existing_tags
+
 # Project
 /public/static
 /public/media

bin/git_annotate_existing_tags.sh

@@ -0,0 +1,58 @@
+#!/bin/sh
+
+# Bug: (2022-03-12) (for a commit after v3.15.0)
+#      Running `git describe` gave unexpected output.
+#      - expect: "v3.15.0-…-g…"
+#      - actual: "v3.7.0-…-g…"
+# Why: 1. Most tags after (and before) v3.7.0 were not annotated. Similar:
+#         https://github.com/Reference-LAPACK/lapack/issues/123
+#      2. Because GitHub uses lightweight tags. Feedback for GitHub:
+#         https://github.com/github/feedback/discussions/4924
+# Fix: Run this script to retroactively annotate lightweight tags.
+#      (Note, this script also re-annotates annotated tags.)
+# Alt: See answers to https://stackoverflow.com/q/21738647/11817077
+#      (More elegant but may not preserve all of tag message with new lines.)
+
+# make output directory
+OUTPUT_DIR='_git_annotate_existing_tags'
+mkdir -p "$OUTPUT_DIR"
+
+# define how to save current status of tag annotation
+function save_tag_summary() {
+  local path=$1
+
+  echo "$(git tag --format='%(creatordate)%09%(refname:strip=2)   %(taggerdate)   %(contents)')" > $path
+}
+
+# define how to annotate tags (will also re-annotate tags)
+function annotate() {
+  local tag=$1
+
+  # get data for tag (some is new for annotation, some must be preserved)
+  local date="$(echo $(git tag --format='%(creatordate)' --list $tag))"
+  local msg="$(git tag --format='%(contents)' --list $tag)"
+  local hash="$(git rev-list -n 1 $tag)"
+
+  # save message to file to preserve new lines
+  local msg_file_path="$OUTPUT_DIR/message.temp"
+  echo "$msg" > $msg_file_path
+
+  # tell the user what we will do
+  echo "Annotate tag $(printf "%9s" $tag) (commit ${hash:0:7}) with date \"$date\" and retain its message \"${msg:0:30}...\"."
+
+  # annotate
+  GIT_COMMITTER_DATE=$date \
+  git tag --annotate --force --file "$msg_file_path" "$tag" "$hash"
+
+  # clean up
+  rm $msg_file_path
+}
+
+# save current status to file for comparison
+save_tag_summary "$OUTPUT_DIR/summary_before.temp"
+
+# annotate each tag passed
+for tag in "$@"; do annotate "$tag"; done
+
+# save new status to file for comparison
+save_tag_summary "$OUTPUT_DIR/summary_after.temp"