[PATCH v2 1/2] bisect: relax requirement for a working tree.

[Jon Seymour <jon.seymour@gmail.com>]

Now that bisection does not require checkout, it can work
on bare repositories too.

In this case, we default the checkout mode to --no-checkout,
thereby forcing the creation of BISECT_HEAD on either a manual
or automatic start.

The require_work_tree check in git-bisect.sh and the NEED_WORK_TREE
check in git.c are relaxed.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jon Seymour <jon.seymour@gmail.com>
---
 Documentation/git-bisect.txt |    2 ++
 git-bisect.sh                |    8 ++++++--
 git.c                        |    2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-bisect.txt b/Documentation/git-bisect.txt
index 41e6ca8..e4f46bc 100644
--- a/Documentation/git-bisect.txt
+++ b/Documentation/git-bisect.txt
@@ -273,6 +273,8 @@ it point to the commit that should be tested.
 +
 This option may be useful when the test you would perform in each step
 does not require a checked out tree.
++
+If the repository is bare, `--no-checkout` is assumed.
 
 EXAMPLES
 --------
diff --git a/git-bisect.sh b/git-bisect.sh
index 22c4da5..72f79d6 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -29,7 +29,6 @@ Please use "git help bisect" to get the full man page.'
 OPTIONS_SPEC=
 . git-sh-setup
 . git-sh-i18n
-require_work_tree
 
 _x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
 _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
@@ -79,7 +78,12 @@ bisect_start() {
 	orig_args=$(git rev-parse --sq-quote "$@")
 	bad_seen=0
 	eval=''
-	mode=''
+	if test "z$(git rev-parse --is-bare-repository)" != zfalse
+	then
+		mode=--no-checkout
+	else
+		mode=
+	fi
 	while [ $# -gt 0 ]; do
 		arg="$1"
 		case "$arg" in
diff --git a/git.c b/git.c
index 8828c18..7fdcab2 100644
--- a/git.c
+++ b/git.c
@@ -320,7 +320,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "annotate", cmd_annotate, RUN_SETUP },
 		{ "apply", cmd_apply, RUN_SETUP_GENTLY },
 		{ "archive", cmd_archive },
-		{ "bisect--helper", cmd_bisect__helper, RUN_SETUP | NEED_WORK_TREE },
+		{ "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 		{ "blame", cmd_blame, RUN_SETUP },
 		{ "branch", cmd_branch, RUN_SETUP },
 		{ "bundle", cmd_bundle, RUN_SETUP_GENTLY },
-- 
1.7.6.522.g810f.dirty