Add autostash command flag to git-gitlab-sync

Utilities/GitSetup/git-gitlab-sync

@@ -21,6 +21,10 @@ OPTIONS
 
 --dry-run
     Show what would be changed without actually updating
+
+--autostash
+    automatically stash/stash pop before and after
+
 '
 OPTIONS_SPEC=
 SUBDIRECTORY_OK=Yes
@@ -32,15 +36,19 @@ egrep-q() {
 
 # Load the project configuration.
 require_work_tree_exists
+state_dir="$GIT_DIR"/gitlab-sync
 
 #-----------------------------------------------------------------------------
 
 remote=''
+autostash="$(git config --bool gitlab.sync.autostash || echo false)"
 dry_run=false
 
 # Parse the command line options.
 while test $# != 0; do
   case "$1" in
+    --autostash)   autostash=true ;;
+    --no-autostash)   autostash=false ;;
     --dry-run)    dry_run=true ;;
     --) shift; break ;;
     -*) usage ;;
@@ -61,6 +69,44 @@ if test -z "$topic" -o "$topic" = "master"; then
 fi
 
 #-----------------------------------------------------------------------------
+apply_autostash () {
+  if test -f "$state_dir/autostash"
+  then
+    stash_sha1=$(cat "$state_dir/autostash")
+    if git stash apply $stash_sha1 2>&1 >/dev/null
+    then
+      gettext 'Applied autostash.'
+    else
+      git stash store -m "autostash" -q $stash_sha1 ||
+      die "$(eval_gettext "Cannot store \$stash_sha1")"
+      gettext 'Applying autostash resulted in conflicts.
+Your changes are safe in the stash.
+You can run "git stash pop" or "git stash drop" at any time.
+'
+    fi
+  fi
+}
+
+finish_sync () {
+  apply_autostash &&
+  { git gc --auto || true; } &&
+  rm -rf "$state_dir"
+}
+
+
+#-----------------------------------------------------------------------------
+if test "$autostash" = true && ! (require_clean_work_tree) 2>/dev/null
+then
+  gettext 'trying to stash local changes' &&
+  stash_sha1=$(git stash create "autostash") ||
+  die "$(gettext 'Cannot autostash')"
+
+  mkdir -p "$state_dir" &&
+  echo $stash_sha1 >"$state_dir/autostash" &&
+  stash_abbrev=$(git rev-parse --short $stash_sha1) &&
+  echo "$(eval_gettext 'Created autostash: $stash_abbrev')" &&
+  git reset --hard
+fi
 
 require_clean_work_tree "sync" "$(gettext "Error syncing \
 We are trying to overwrite all local changes on this branch with the version on \
@@ -84,5 +130,6 @@ then
   fi
 fi
 
+finish_sync
 # Reproduce the push exit code.
 exit $fetch_exit