git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH] git-bisect.sh: don't accidentally override existing branch "bisect"

From
Gerrit Pape <pape@smarden.org>
Date
Apr 30, 2008, 16:46 UTC
Message-ID
<20080430164613.28314.qmail@b31db398e1accc.315fe32.mid.smarden.org>

If a branch named "bisect" or "new-bisect" already was created in the repo by other means than git bisect, doing a git bisect used to override the branch without a warning. Now if the branch "bisect" or "new-bisect" already exists, and it was not created by git bisect itself, git bisect start fails with an appropriate error message. Additionally, if checking out a new bisect state fails due to a merge problem, git bisect cleans up the temporary branch "new-bisect".

The accidental override has been noticed by Andres Salomon, reported
through
 http://bugs.debian.org/478647
Signed-off-by: Gerrit Pape <pape@smarden.org>
---
 Documentation/git-bisect.txt |    2 +-
 git-bisect.sh                |   20 ++++++++++++++------
 t/t6030-bisect-porcelain.sh  |   18 ++++++++++++++++++
 3 files changed, 33 insertions(+), 7 deletions(-)
diff --git a/Documentation/git-bisect.txt b/Documentation/git-bisect.txt
index 698ffde..1c7e38d 100644
--- a/Documentation/git-bisect.txt
+++ b/Documentation/git-bisect.txt
@@ -85,7 +85,7 @@ Oh, and then after you want to reset to the original head, do a
 $ git bisect reset
 ------------------------------------------------
 
-to get back to the master branch, instead of being in one of the
+to get back to the original branch, instead of being in one of the
 bisection branches ("git bisect start" will do that for you too,
 actually: it will reset the bisection state, and before it does that
 it checks that you're not using some old bisection branch).
diff --git a/git-bisect.sh b/git-bisect.sh
index d8d9bfd..48d81d5 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -69,14 +69,19 @@ bisect_start() {
 	head=$(GIT_DIR="$GIT_DIR" git symbolic-ref -q HEAD) ||
 	head=$(GIT_DIR="$GIT_DIR" git rev-parse --verify HEAD) ||
 	die "Bad HEAD - I need a HEAD"
+	#
+	# Check that we either already have BISECT_START, or that the
+	# branches bisect, new-bisect don't exist, to not override them.
+	#
+	test -s "$GIT_DIR/BISECT_START" ||
+		if git show-ref bisect > /dev/null ||
+		    git show-ref new-bisect > /dev/null; then
+			die 'The branches "bisect" and "new-bisect" must not exist.'
+		fi
 	start_head=''
 	case "$head" in
 	refs/heads/bisect)
-		if [ -s "$GIT_DIR/BISECT_START" ]; then
-		    branch=`cat "$GIT_DIR/BISECT_START"`
-		else
-		    branch=master
-		fi
+		branch=`cat "$GIT_DIR/BISECT_START"`
 		git checkout $branch || exit
 		;;
 	refs/heads/*|$_x40)
@@ -329,7 +334,10 @@ bisect_next() {
 
 	echo "Bisecting: $bisect_nr revisions left to test after this"
 	git branch -f new-bisect "$bisect_rev"
-	git checkout -q new-bisect || exit
+	git checkout -q new-bisect || {
+		git branch -d new-bisect
+		exit
+	}
 	git branch -M new-bisect bisect
 	git show-branch "$bisect_rev"
 }
diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index 5e3e544..05f1e15 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@@ -284,6 +284,24 @@ test_expect_success 'bisect starting with a detached HEAD' '
 
 '
 
+test_expect_success 'bisect refuses to start if branch bisect exists' '
+	git bisect reset &&
+	git branch bisect &&
+	test_must_fail git bisect start &&
+	git branch -d bisect &&
+	git checkout -b bisect &&
+	test_must_fail git bisect start &&
+	git checkout master &&
+	git branch -d bisect
+'
+
+test_expect_success 'bisect refuses to start if branch new-bisect exists' '
+	git bisect reset &&
+	git branch new-bisect &&
+	test_must_fail git bisect start &&
+	git branch -d new-bisect
+'
+
 #
 #
 test_done
-- 
1.5.5.1
Next: Christian Couder
Message 1 of 11 in “git-bisect.sh: don't accidentally override existing branch "bisect"”
  1. git-bisect.sh: don't accidentally override existing branch "bisect"Gerrit Pape, Apr 30, 2008
  2. Christian CouderApr 30, 2008
  3. Richard QuirkMay 1, 2008
  4. Christian CouderMay 1, 2008
  5. git-bisect.sh: don't accidentally override existing branch "bisect"Gerrit Pape, May 2, 2008
  6. Christian CouderMay 3, 2008
  7. git-bisect.sh: don't accidentally override existing branch "bisect"Gerrit Pape, May 5, 2008
  8. Christian CouderMay 6, 2008
  9. Karl HasselströmMay 2, 2008
  10. Junio C HamanoMay 2, 2008
  11. Johannes SchindelinMay 3, 2008

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.