transport-helper: pass --signed-tags=warn-strip to fast-export

Currently, attempting to push a signed tag to a remote helper which uses
fast-export results in the remote helper failing because the default
fast-export action for signed tags is "abort".  This is not helpful for
users because there is no way to pass additional arguments to
fast-export here, either from the remote helper or from the command
line.

In general, the signature will be invalidated by whatever transformation
a remote helper performs on a tag to push it to a repository in a
different format so the correct behaviour is to strip the tag.  Doing
this silently may surprise people, so use "warn-strip" to issue a
warning when a signed tag is encountered.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/transport-helper.c b/transport-helper.c
index dcd8d97411..3ce825989e 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -410,9 +410,10 @@ static int get_exporter(struct transport *transport,
 	/* we need to duplicate helper->in because we want to use it after
 	 * fastexport is done with it. */
 	fastexport->out = dup(helper->in);
-	fastexport->argv = xcalloc(5 + revlist_args->nr, sizeof(*fastexport->argv));
+	fastexport->argv = xcalloc(6 + revlist_args->nr, sizeof(*fastexport->argv));
 	fastexport->argv[argc++] = "fast-export";
 	fastexport->argv[argc++] = "--use-done-feature";
+	fastexport->argv[argc++] = "--signed-tags=warn-strip";
 	if (data->export_marks)
 		fastexport->argv[argc++] = data->export_marks;
 	if (data->import_marks)