[PATCH 2/2] checkout: forbid "-B <branch>" from touching a branch used elsewhere
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Nov 23, 2023, 06:00 UTC
- Message-ID
- <xmqqpm01au0w.fsf_-_@gitster.g>
- In-Reply-To
- <xmqqv89tau3r.fsf@gitster.g>
"git checkout -B <branch> [<start-point>]", being a "forced" version of "-b", switches to the <branch>, after optionally resetting its tip to the <start-point>, even if the <branch> is in use in another worktree, which is somewhat unexpected.
Protect the <branch> using the same logic that forbids "git checkout <branch>" from touching a branch that is in use elsewhere.
This is a breaking change that may deserve backward compatibliity warning in the Release Notes. The "--ignore-other-worktrees" option can be used as an escape hatch if the finger memory of existing users depend on the current behaviour of "-B".
Reported-by: Willem Verstraeten <willem.verstraeten@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> ---
* The documentation might also need updates, but I didn't look at.
builtin/checkout.c | 7 +++++++ t/t2060-switch.sh | 2 ++ t/t2400-worktree-add.sh | 8 ++++++++ 3 files changed, 17 insertions(+)
diff --git a/builtin/checkout.c b/builtin/checkout.c index b4ab972c5a..8a8ad23e98 100644 --- a/builtin/checkout.c +++ b/builtin/checkout.c @@ -1600,6 +1600,13 @@ static int checkout_branch(struct checkout_opts *opts, if (new_branch_info->path && !opts->force_detach && !opts->new_branch) die_if_switching_to_a_branch_in_use(opts, new_branch_info->path); + /* "git checkout -B <branch>" */ + if (opts->new_branch_force) { + char *full_ref = xstrfmt("refs/heads/%s", opts->new_branch); + die_if_switching_to_a_branch_in_use(opts, full_ref); + free(full_ref); + } + if (!new_branch_info->commit && opts->new_branch) { struct object_id rev; int flag; diff --git a/t/t2060-switch.sh b/t/t2060-switch.sh index e247a4735b..c91c4db936 100755 --- a/t/t2060-switch.sh +++ b/t/t2060-switch.sh @@ -170,8 +170,10 @@ test_expect_success 'switch back when temporarily detached and checked out elsew # we test in both worktrees to ensure that works # as expected with "first" and "next" worktrees test_must_fail git -C wt1 switch shared && + test_must_fail git -C wt1 switch -C shared && git -C wt1 switch --ignore-other-worktrees shared && test_must_fail git -C wt2 switch shared && + test_must_fail git -C wt2 switch -C shared && git -C wt2 switch --ignore-other-worktrees shared ' diff --git a/t/t2400-worktree-add.sh b/t/t2400-worktree-add.sh index df4aff7825..bbcb2d3419 100755 --- a/t/t2400-worktree-add.sh +++ b/t/t2400-worktree-add.sh @@ -126,6 +126,14 @@ test_expect_success 'die the same branch is already checked out' ' ) ' +test_expect_success 'refuse to reset a branch in use elsewhere' ' + ( + cd here && + test_must_fail git checkout -B newmain 2>actual && + grep "already used by worktree at" actual + ) +' + test_expect_success SYMLINKS 'die the same branch is already checked out (symlink)' ' head=$(git -C there rev-parse --git-path HEAD) && ref=$(git -C there symbolic-ref HEAD) &&
-- 2.43.0