From 73697a0b572f7f216d8355d83bf69e9b42e9a077 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Date: Tue, 25 Sep 2007 16:43:15 +0100
Subject: [PATCH] rebase -i: work on a detached HEAD

Earlier, rebase -i refused to rebase a detached HEAD.  Now it no longer
does.

Incidentally, this fixes "git gc --auto" shadowing the true exit status.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 git-rebase--interactive.sh    | 23 +++++++++++++++--------
 t/t3404-rebase-interactive.sh |  8 ++++++++
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 8e6e9431e8..823291d4af 100755
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -317,17 +317,20 @@ do_next () {
 	else
 		NEWHEAD=$(git rev-parse HEAD)
 	fi &&
-	message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
-	git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
-	git symbolic-ref HEAD $HEADNAME && {
+	case $HEADNAME in
+	refs/*)
+		message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
+		git update-ref -m "$message" $HEADNAME $NEWHEAD $OLDHEAD &&
+		git symbolic-ref HEAD $HEADNAME
+		;;
+	esac && {
 		test ! -f "$DOTEST"/verbose ||
 			git diff --stat $(cat "$DOTEST"/head)..HEAD
 	} &&
 	rm -rf "$DOTEST" &&
+	git gc --auto &&
 	warn "Successfully rebased and updated $HEADNAME."
 
-	git gc --auto
-
 	exit
 }
 
@@ -367,7 +370,11 @@ do
 
 		HEADNAME=$(cat "$DOTEST"/head-name)
 		HEAD=$(cat "$DOTEST"/head)
-		git symbolic-ref HEAD $HEADNAME &&
+		case $HEADNAME in
+		refs/*)
+			git symbolic-ref HEAD $HEADNAME
+			;;
+		esac &&
 		output git reset --hard $HEAD &&
 		rm -rf "$DOTEST"
 		exit
@@ -445,8 +452,8 @@ do
 		test -z "$ONTO" && ONTO=$UPSTREAM
 
 		: > "$DOTEST"/interactive || die "Could not mark as interactive"
-		git symbolic-ref HEAD > "$DOTEST"/head-name ||
-			die "Could not get HEAD"
+		git symbolic-ref HEAD > "$DOTEST"/head-name 2> /dev/null ||
+			echo "detached HEAD" > "$DOTEST"/head-name
 
 		echo $HEAD > "$DOTEST"/head
 		echo $UPSTREAM > "$DOTEST"/upstream
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 1af73a47c6..f2214dd0fa 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -309,4 +309,12 @@ test_expect_success '--continue tries to commit, even for "edit"' '
 	test $parent = $(git rev-parse HEAD^)
 '
 
+test_expect_success 'rebase a detached HEAD' '
+	grandparent=$(git rev-parse HEAD~2) &&
+	git checkout $(git rev-parse HEAD) &&
+	test_tick &&
+	FAKE_LINES="2 1" git rebase -i HEAD~2 &&
+	test $grandparent = $(git rev-parse HEAD~2)
+'
+
 test_done