Merge branch 'sg/bash-prompt-dirty-orphan'

Produce correct "dirty" marker for shell prompts, even when we
are on an orphan or an unborn branch.

* sg/bash-prompt-dirty-orphan:
  bash prompt: indicate dirty index even on orphan branches
  bash prompt: remove a redundant 'git diff' option
  bash prompt: test dirty index and worktree while on an orphan branch

contrib/completion/git-prompt.sh

@@ -476,10 +476,9 @@ __git_ps1 ()
 		if [ -n "${GIT_PS1_SHOWDIRTYSTATE-}" ] &&
 		   [ "$(git config --bool bash.showDirtyState)" != "false" ]
 		then
-			git diff --no-ext-diff --quiet --exit-code || w="*"
-			if [ -n "$short_sha" ]; then
-				git diff-index --cached --quiet HEAD -- || i="+"
-			else
+			git diff --no-ext-diff --quiet || w="*"
+			git diff --no-ext-diff --cached --quiet || i="+"
+			if [ -z "$short_sha" ] && [ -z "$i" ]; then
 				i="#"
 			fi
 		fi