There are two problems with -m (rename) and -c (copy) branch operations.
1. If we force-rename or force-copy a branch to overwrite another
branch that already has configuration, the resultant branch ends up
with the source configuration (if any) mixed with the configuration for
the overwritten branch.
$ git branch upstream
$ git branch -t foo upstream # foo has tracking configuration
$ git branch bar # bar has not
$ git branch -M bar foo # force-rename bar to foo
$ git config branch.foo.merge # must return clear
refs/heads/upstream
2. If we repeatedly force-copy a branch to the same name, the branch
configuration is repeatedly copied each time.
$ git branch upstream
$ git branch -t foo upstream # foo has tracking configuration
$ git branch -c foo bar # bar is a copy of foo
$ git branch -C foo bar # again
$ git branch -C foo bar # ..
$ git config --get-all branch.bar.merge # must return one value
refs/heads/upstream
refs/heads/upstream
refs/heads/upstream
Whenever we copy or move (forced or not) we must make sure that there is
no residual configuration that will be, probably erroneously, inherited
by the new branch. To avoid confusions, clear any branch configuration
before setting the configuration from the copied or moved branch.
Signed-off-by: Rubén Justo <rjusto@xxxxxxxxx>
---
builtin/branch.c | 17 +++++++++++------
t/t3200-branch.sh | 19 +++++++++++++++++++
2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/builtin/branch.c b/builtin/branch.c
index a35e174aae..14664f0278 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -583,12 +583,17 @@ static void copy_or_rename_branch(const char *oldname, const char *newname, int
strbuf_release(&logmsg);
- strbuf_addf(&oldsection, "branch.%s", interpreted_oldname);
- strbuf_addf(&newsection, "branch.%s", interpreted_newname);
- if (!copy && git_config_rename_section(oldsection.buf, newsection.buf) < 0)
- die(_("Branch is renamed, but update of config-file failed"));
- if (copy && strcmp(interpreted_oldname, interpreted_newname) && git_config_copy_section(oldsection.buf, newsection.buf) < 0)
- die(_("Branch is copied, but update of config-file failed"));
+ if (strcmp(interpreted_oldname, interpreted_newname)) {
+ strbuf_addf(&oldsection, "branch.%s", interpreted_oldname);
+ strbuf_addf(&newsection, "branch.%s", interpreted_newname);
+
+ delete_branch_config(interpreted_newname);
+
+ if (!copy && git_config_rename_section(oldsection.buf, newsection.buf) < 0)
+ die(_("Branch is renamed, but update of config-file failed"));
+ if (copy && git_config_copy_section(oldsection.buf, newsection.buf) < 0)
+ die(_("Branch is copied, but update of config-file failed"));
+ }
strbuf_release(&oldref);
strbuf_release(&newref);
strbuf_release(&oldsection);
diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index 7f605f865b..c3b3d11c28 100755
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -218,6 +218,25 @@ test_expect_success 'git branch -M should leave orphaned HEAD alone' '
)
'
+test_expect_success 'git branch -M inherites clean tracking setup' '
+ test_when_finished git branch -D moved &&
+ git branch -t main-tracked main &&
+ git branch non-tracked &&
+ git branch -M main-tracked moved &&
+ git branch --unset-upstream moved &&
+ git branch -M non-tracked moved &&
+ test_must_fail git branch --unset-upstream moved
+'
+
+test_expect_success 'git branch -C inherites clean tracking setup' '
+ test_when_finished git branch -D copiable copied &&
+ git branch -t copiable main &&
+ git branch -C copiable copied &&
+ git branch --unset-upstream copied &&
+ git branch -C copied copiable &&
+ test_must_fail git branch --unset-upstream copiable
+'
+
test_expect_success 'resulting reflog can be shown by log -g' '
oid=$(git rev-parse HEAD) &&
cat >expect <<-EOF &&
--
2.36.1
