From: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date: Wed, 12 Jun 2019 08:56:06 +0000 (+0700)
Subject: completion: do not cache if --git-completion-helper fails
X-Git-Tag: v2.23.0-rc0~88^2
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/69702523afb4de692b415648e53fcfb1b4630f18?hp=aeb582a98374c094361cba1bd756dc6307432c42

completion: do not cache if --git-completion-helper fails

"git <cmd> --git-completion-helper" could fail if the command checks for
a repo before parse_options(). If the result is cached, later on when
the user moves to a worktree with repo, tab completion will still fail.

Avoid this by detecting errors and not cache the completion output. We
can try again and hopefully succeed next time (e.g. when a repo is
found).

Of course if --git-completion-helper fails permanently because of other
reasons (*), this will slow down completion. But I don't see any better
option to handle that case.

(*) one of those cases is if __gitcomp_builtin is called on a command
that does not support --git-completion-helper. And we do have a
generic call

__git_complete_common "$command"

but this case is protected with __git_support_parseopt_helper so we're
good.

Reported-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 499e56f83d..00cc695e3d 100644
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -400,7 +400,8 @@ __gitcomp_builtin ()
 	if [ -z "$options" ]; then
 		# leading and trailing spaces are significant to make
 		# option removal work correctly.
-		options=" $incl $(__git ${cmd/_/ } --git-completion-helper) "
+		options=" $incl $(__git ${cmd/_/ } --git-completion-helper) " || return
+
 		for i in $excl; do
 			options="${options/ $i / }"
 		done