Bisect reset: do nothing when not bisecting.

Before this patch, using "git bisect reset" when not bisecting
did a "git checkout master" for no good reason.

This also happened using "git bisect replay" when not bisecting
because "bisect_replay" starts by calling "bisect_reset".

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

2 files changed, 30 insertions, 1 deletions

diff --git a/git-bisect.sh b/git-bisect.sh
index 414f813be7..6f20a297a5 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -328,6 +328,10 @@ bisect_visualize() {
 }
 
 bisect_reset() {
+	test -f "$GIT_DIR/BISECT_NAMES" || {
+		echo "We are not bisecting."
+		return
+	}
 	case "$#" in
 	0) if [ -s "$GIT_DIR/head-name" ]; then
 	       branch=`cat "$GIT_DIR/head-name"`
diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index f09db6244e..2ba4b00e52 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@@ -71,6 +71,31 @@ test_expect_success 'bisect start with one bad and good' '
 	git bisect next
 '
 
+test_expect_success 'bisect reset: back in the master branch' '
+	git bisect reset &&
+	echo "* master" > branch.expect &&
+	git branch > branch.output &&
+	cmp branch.expect branch.output
+'
+
+test_expect_success 'bisect reset: back in another branch' '
+	git checkout -b other &&
+	git bisect start &&
+	git bisect good $HASH1 &&
+	git bisect bad $HASH3 &&
+	git bisect reset &&
+	echo "  master" > branch.expect &&
+	echo "* other" >> branch.expect &&
+	git branch > branch.output &&
+	cmp branch.expect branch.output
+'
+
+test_expect_success 'bisect reset when not bisecting' '
+	git bisect reset &&
+	git branch > branch.output &&
+	cmp branch.expect branch.output
+'
+
 test_expect_success 'bisect reset removes packed refs' '
 	git bisect reset &&
 	git bisect start &&
@@ -179,7 +204,7 @@ test_expect_success 'bisect skip: add line and then a new test' '
 	git bisect skip &&
 	git bisect good > my_bisect_log.txt &&
 	grep "$HASH5 is first bad commit" my_bisect_log.txt &&
-	git bisect log > log_to_replay.txt
+	git bisect log > log_to_replay.txt &&
 	git bisect reset
 '