chore(monorepo): stash in pre-commit to avoid all changes to partially commited files to end up in commit (#7559)

* chore(monorepo): stash in pre-commit to avoid all changes to partially commited files to end up in commit

* fix(pre-commit): don't stash staged changes mixed with unstaged to avoid merge conflicts on pop

* chore(pre-commit): quiet

Author: gribnoysup

.husky/pre-commit

@@ -4,6 +4,19 @@
 # listings staged files only
 fileList=$(git diff --diff-filter=AM --cached --name-only)
 
+# making sure that pre-commit hook preserves the partial commits where only some
+# hunks are staged for commit
+# 1. stash only staged files first (there's no option to stash only uncommited
+#    files, so we have to reverse the logic)
+git stash --staged -m "pre-commit hook: staged" -q
+# 2. stash everything that's left
+git stash -m "pre-commit hook: unstaged" -q
+# 3. restore staged state
+git stash pop stash@{1} -q
+
+# when script exits, pop the stash with unstaged files
+trap "git stash pop -q" EXIT
+
 if [ -n "$fileList" ]; then
   echo "Prettifying staged files..."
   npx prettier-compass --write --ignore-unknown $fileList