Re: Is reserving the branch name "bisect" a good thing?
>> Would it be better if "git bisect" followed that rule as well?
>> Otherwise, we really should document the reserved word.
> I wonder if you broke "git bisect visualize" with that patch.
I don't know, but I sure broke git-bisect.
The problem is that git-checkout won't switch branches if the ref given is not in $GIT_DIR/refs/heads. (Try to include a "heads/" prefix on a non-selected existing branch to see.)
Without changing this policy in git-checkout, or replicating most of git-checkout's code in git-bisect, I can't get away from using a head name in refs/heads/. :-(
Stepping back, the problem is that
- git has a policy against allowing checkins against a ref not in refs/heads/
- git-commit doesn't have a concept of an unwriteable HEAD, so
- git-checkout refuses to set HEAD to an unwriteable ref (not in refs/heads/)
But "git bisect" wants exactly this sort of historical snapshot.
Actually, this leads to a question... suppose I want to manually check out some old revision (like "v.2.6.12") for some reason (performance testing, say). How do I do that? Do I have to create a branch just to do that?
It might be nicer to allow such a checkout and do the checking in git-commit, telling you to "git-checkout -b <new_branch>" before you check in your edits.
In git-bisect, I finally managed to do a bit of a hack, but it's a bit annoying for doing the above from the command line. (Error handling could also probably use improvement.)
See the "@@ -146,10 +160,12 @@ bisect_next() {" chunk, third from the end, for the meat.
diff --git a/git-bisect.sh b/git-bisect.sh
index 68838f3..c8b9d7b 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -1,6 +1,9 @@
#!/bin/sh
. git-sh-setup
+# Put arguments in single quotes to they can be re-interpreted by the shell.
+# (To put a single quote in a single-quoted string, you need to write
+# 'wasn'\''t' = 'wasn' + \' + 't'.)
sq() {
perl -e '
for (@ARGV) {
@@ -42,6 +45,18 @@ bisect_autostart() {
}
}
+# Not generally needed, but provide a cleanup function
+bisect_stop() {
+ case "$(cat "$GIT_DIR/HEAD")" in
+ refs/bisect/*)
+ echo "Resetting HEAD to master"
+ git checkout master || exit
+ ;;
+ esac
+ rm -rf "$GIT_DIR/refs/bisect/"
+ rm -f "$GIT_DIR/BISECT_LOG" "$GIT_DIR/BISECT_NAMES"
+}
+
bisect_start() {
#
# Verify HEAD. If we were bisecting before this, reset to the
@@ -50,7 +65,7 @@ bisect_start() {
head=$(GIT_DIR="$GIT_DIR" git-symbolic-ref HEAD) ||
die "Bad HEAD - I need a symbolic ref"
case "$head" in
- refs/heads/bisect*)
+ refs/bisect/*)
git checkout master || exit
;;
refs/heads/*)
@@ -63,7 +78,6 @@ bisect_start() {
#
# Get rid of any old bisect state
#
- rm -f "$GIT_DIR/refs/heads/bisect"
rm -rf "$GIT_DIR/refs/bisect/"
mkdir "$GIT_DIR/refs/bisect"
{
@@ -146,10 +160,12 @@ bisect_next() {
fi
nr=$(eval "git-rev-list $rev $good -- $(cat $GIT_DIR/BISECT_NAMES)" | wc -l) || exit
echo "Bisecting: $nr revisions left to test after this"
- echo "$rev" > "$GIT_DIR/refs/heads/new-bisect"
- git checkout new-bisect || exit
- mv "$GIT_DIR/refs/heads/new-bisect" "$GIT_DIR/refs/heads/bisect" &&
- GIT_DIR="$GIT_DIR" git-symbolic-ref HEAD refs/heads/bisect
+ next="$(TMPDIR="$GIT_DIR/refs/heads" tempfile -p bisect)"
+ echo "$rev" > "$next"
+ # checkout refuses to deal with a head name not in refs/heads...
+ git checkout $(basename "$next")
+ mv "$next" "$GIT_DIR/refs/bisect/current" &&
+ GIT_DIR="$GIT_DIR" git-symbolic-ref HEAD refs/bisect/current
git-show-branch "$rev"
}
@@ -172,7 +188,6 @@ bisect_reset() {
esac
git checkout "$branch" &&
rm -fr "$GIT_DIR/refs/bisect"
- rm -f "$GIT_DIR/refs/heads/bisect"
rm -f "$GIT_DIR/BISECT_LOG"
}
@@ -217,6 +232,8 @@ case "$#" in
case "$cmd" in
start)
bisect_start "$@" ;;
+ stop)
+ bisect_stop "$@" ;;
bad)
bisect_bad "$@" ;;
good)
