git_reference_rename eagerly delete references #4301

void test_wip_wip__renaming_borked_new_ref_doesnt_delete_old(void)
{
	git_reference *head_ref, *current_ref, *renamed_ref;
	int err;
	git_oid oid;
	git_reference *victim_ref;
	git_buf victim_path = GIT_BUF_INIT;
	struct stat victim_stat;
	__uint32_t victim_flags;

	cl_git_pass(git_repository_head(&head_ref, g_repo));
	cl_git_pass(git_reference_resolve(&current_ref, head_ref));

	cl_git_pass(git_reference_name_to_id(&oid, g_repo, "refs/heads/master"));
	cl_git_pass(git_reference_create(&victim_ref, g_repo, VICTIM_REFNAME, &oid, 1, NULL));

	git_buf_joinpath(&victim_path, git_repository_path(g_repo), git_reference_name(victim_ref));

	cl_must_pass(p_stat(git_buf_cstr(&victim_path), &victim_stat));
	victim_flags = victim_stat.st_flags;

	cl_must_pass(chflags(git_buf_cstr(&victim_path), victim_flags|UF_IMMUTABLE));

	err = git_reference_rename(&renamed_ref, current_ref, git_reference_name(victim_ref), 1, NULL);

	cl_must_pass(chflags(git_buf_cstr(&victim_path), victim_flags));
	git_buf_free(&victim_path);

	cl_git_fail_with(GIT_ERROR, err);

	cl_git_pass(git_reference_resolve(&current_ref, head_ref));

	git_reference_free(victim_ref);
}