list-objects-filter-options: allow mult. --filter

Allow combining of multiple filters by simply repeating the --filter
flag. Before this patch, the user had to combine them in a single flag
somewhat awkwardly (e.g. --filter=combine:FOO+BAR), including
URL-encoding the individual filters.

To make this work, in the --filter flag parsing callback, rather than
error out when we detect that the filter_options struct is already
populated, we modify it in-place to contain the added sub-filter. The
existing sub-filter becomes the lhs of the combined filter, and the
next sub-filter becomes the rhs. We also have to URL-encode the LHS and
RHS sub-filters.

We can simplify the operation if the LHS is already a combine: filter.
In that case, we just append the URL-encoded RHS sub-filter to the LHS
spec to get the new spec.

Helped-by: Emily Shaffer <emilyshaffer@google.com>
Helped-by: Jeff Hostetler <git@jeffhostetler.com>
Helped-by: Jeff King <peff@peff.net>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/upload-pack.c b/upload-pack.c
index d404d88941..f8a76ebda3 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -883,6 +883,7 @@ static void receive_needs(struct packet_reader *reader, struct object_array *wan
 		if (skip_prefix(reader->line, "filter ", &arg)) {
 			if (!filter_capability_requested)
 				die("git upload-pack: filtering capability not negotiated");
+			list_objects_filter_die_if_populated(&filter_options);
 			parse_list_objects_filter(&filter_options, arg);
 			continue;
 		}
@@ -1304,6 +1305,7 @@ static void process_args(struct packet_reader *request,
 		}
 
 		if (allow_filter && skip_prefix(arg, "filter ", &p)) {
+			list_objects_filter_die_if_populated(&filter_options);
 			parse_list_objects_filter(&filter_options, p);
 			continue;
 		}