[PATCH v2 2/3] p9210: fix 'scalar clone' when running from a detached HEAD

From: Philippe Blain <levraiphilippeblain@gmail.com>

In p9210-scalar-clone.sh, we test using 'scalar clone' to clone $GIT_PERF_LARGE_REPO (copied locally as 'to-clone'), which defaults to the git.git checkout we are running the test from.

When --branch is not specified (as in this test), 'scalar clone' tries to get the default branch of the remote repository by parsing the output of 'git ls-remote --symref $URL HEAD', as implemented in scalar.c:remote_default_branch. When the git.git checkout we are running the test from is in detached HEAD, this fails and we fall back to using the name of the currently checked out branch in the newly initialized repository, which in this case is the value returned earlier in cmd_clone by repo_default_branch_name.

We then invoke 'git checkout -t origin/$branch', with $branch being the name we got from remote_default_branch. This invocation fails if '$branch' does not exist as a branch in the current git.git checkout.

Fix this by creating a local branch in 'to-clone' in the setup test "enable server-side partial clone", making sure to use '-B' in case a branch named 'test-branch' already exists.

Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
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 t/perf/p9210-scalar.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)