Add changelog generator script

README.md

@@ -188,6 +188,7 @@ npm run check:all
 ```shell
 npm version minor
 git push --tags && git push
+./scripts/changelog
 npm login --registry https://registry.npmjs.org --scope=@salamivg
 npm publish --access public
 ```

scripts/changelog.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+
+from=$1
+to=$2
+
+if [ "$from" == "" ]; then
+  from=$(git describe --abbrev=0 $(git describe --abbrev=0)^)
+  echo "No 'from' positional arg provided. Defaulting to '$from'"
+fi
+
+if [ "$to" == "" ]; then
+  to=$(git describe --abbrev=0)
+  echo "No 'to' positional arg provided. Defaulting to '$to'"
+fi
+
+echo "\nChangelog from $from to $to\n"
+
+# Some formatting explanations:
+#   %h: short sha
+#   %ad: author date, using --date option for format
+#   %s: "subject" (probably the first line of the commit message, but haven't tested extensively)
+#   %an: author name
+#   %d: ref name; prints stuff like "(HEAD -> main, tag: v0.4.0, origin/main, origin/HEAD)"
+git log \
+  --abbrev-commit \
+  --decorate \
+  --date=short \
+  --format=format:'* %s (%ad, [%h](https://github.com/ericyd/salamivg/commit/%H))' \
+  --all \
+  "$from"..."$to"
+
+# a nice one-liner that shows most of the useful info
+# git log --abbrev-commit --decorate --date=short --format=format:'%h, %aI - %s %d' --all "$from"..."$to"