From 1db770da2b41b1ed02061f5145a2d8abc6e9c22c Mon Sep 17 00:00:00 2001
From: Sean Whitton <spwhitton@spwhitton.name>
Date: Mon, 22 Jul 2019 16:17:34 +0100
Subject: git-debpush: Check for a detached head when pushing HEAD

See discussion in #932612.

Suggested-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
Signed-off-by: Sean Whitton <spwhitton@spwhitton.name>
---
 git-debpush       | 8 ++++++++
 git-debpush.1.pod | 6 ++++++
 2 files changed, 14 insertions(+)

diff --git a/git-debpush b/git-debpush
index 402b1dd..c3b067d 100755
--- a/git-debpush
+++ b/git-debpush
@@ -230,6 +230,14 @@ case "$quilt_mode" in
     *) badusage "invalid quilt mode: $quilt_mode" ;;
 esac
 
+# **** Early sanity check ****
+
+if [ "$branch" = "HEAD" ] \
+       && ! git symbolic-ref --quiet HEAD >/dev/null; then
+    fail_check detached \
+               "HEAD is detached; you probably don't want to debpush it"
+fi
+
 # **** Gather git information ****
 
 remoteconfigs=()
diff --git a/git-debpush.1.pod b/git-debpush.1.pod
index b9a908e..5e40e3c 100644
--- a/git-debpush.1.pod
+++ b/git-debpush.1.pod
@@ -243,6 +243,12 @@ git-debrebase(1) branch in an unstitched state (see git-debrebase(5)).
 
 =back
 
+=item B<detached>
+
+Ignore the fact that HEAD is to be tagged, but HEAD is detached (this
+check is only run when B<--branch=HEAD> or no B<--branch> option is
+specified).
+
 =back
 
 =head1 SEE ALSO
-- 
cgit v1.2.3