From b9f2e1a684e3729b0278950cd7e930441d84c9f1 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Sat, 30 Mar 2024 14:37:14 -0700 Subject: [PATCH] checkout: omit "tracking" information on a detached HEAD By definition, a detached HEAD state is tentative and there is no configured "upstream" that it always wants to integrate with. But if you detach from a branch that is behind its upstream, e.g., $ git checkout -t -b main origin/main $ git checkout main $ git reset --hard HEAD^ $ git checkout --detach main you'd see "you are behind your upstream origin/main". This does not happen when you replace the last step in the above with any of these $ git checkout HEAD^0 $ git checkout --detach HEAD $ git checkout --detach origin/main Before 32669671 (checkout: introduce --detach synonym for "git checkout foo^{commit}", 2011-02-08) introduced the "--detach" option, the rule to decide if we show the tracking information used to be: If --quiet is not given, and if the given branch name is a real local branch (i.e. the one we can compute the file path under .git/, like 'refs/heads/master' or "HEAD" which stand for the name of the current branch", then give the tracking information. to exclude things like "git checkout master^0" (which was the official way to detach HEAD at the commit before that commit) and "git checkout origin/master^0" from showing tracking information, but still do show the tracking information for the current branch for "git checkout HEAD". The introduction of an explicit option "--detach" broke this subtley. The new rule should have been If --quiet is given, do not bother with tracking info. If --detach is given, do not bother with tracking info. Otherwise, if we know that the branch name given is a real local branch, or if we were given "HEAD" and "HEAD" is not detached, then attempt to show the tracking info. but it allowed "git checkout --detach master" to also show the tracking info by mistake. Let's tighten the rule to fix this. Reported-by: mirth hickford Signed-off-by: Junio C Hamano --- builtin/checkout.c | 3 ++- t/t2020-checkout-detach.sh | 5 ++++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/builtin/checkout.c b/builtin/checkout.c index 2e8b0d18f4..26e1a64569 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1030,7 +1030,8 @@ static void update_refs_for_switch(const struct checkout_opts *opts, remove_branch_state(the_repository, !opts->quiet); strbuf_release(&msg); if (!opts->quiet && - (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD")))) + !opts->force_detach && + (new_branch_info->path || !strcmp(new_branch_info->name, "HEAD"))) report_tracking(new_branch_info); } diff --git a/t/t2020-checkout-detach.sh b/t/t2020-checkout-detach.sh index bce284c297..8d90d02850 100755 --- a/t/t2020-checkout-detach.sh +++ b/t/t2020-checkout-detach.sh @@ -176,7 +176,10 @@ test_expect_success 'tracking count is accurate after orphan check' ' git config branch.child.merge refs/heads/main && git checkout child^ && git checkout child >stdout && - test_cmp expect stdout + test_cmp expect stdout && + + git checkout --detach child >stdout && + test_grep ! "can be fast-forwarded\." stdout ' test_expect_success 'no advice given for explicit detached head state' '