Re: [PATCH 2/2] prune.c: only print informational message in show_only or verbose mode

Junio C Hamano [off-list ref] writes:

Note that this chooses to expose what comes out of the standard
output of the subprocess to the standard error to be shown to the
user sitting on the other end.  This is in line with what we do to
all of our hooks (Cf. cd83c74 (Redirect update hook stdout to
stderr., 2006-12-30)).

Ok, now a tested patch, on top of your 1/2

-- >8 --
Subject: [PATCH] receive-pack: do not leak output from auto-gc to standard output

The standard output channel of receive-pack is a structured protocol
channel, and subprocesses must never be allowed to leak anything
into it by writing to their standard output.

Use RUN_COMMAND_STDOUT_TO_STDERR option to run_command_v_opt() just
like we do when running hooks to prevent output from "gc" leaking to
the standard output.

Signed-off-by: Junio C Hamano <redacted>
---
 builtin/receive-pack.c | 3 ++-
 t/t5400-send-pack.sh   | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 0afb8b2..3f05d97 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c

@@ -977,7 +977,8 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 			const char *argv_gc_auto[] = {
 				"gc", "--auto", "--quiet", NULL,
 			};
-			run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
+			int opt = RUN_GIT_CMD | RUN_COMMAND_STDOUT_TO_STDERR;
+			run_command_v_opt(argv_gc_auto, opt);
 		}
 		if (auto_update_server_info)
 			update_server_info(0);

diff --git a/t/t5400-send-pack.sh b/t/t5400-send-pack.sh
index 04a8791..250c720 100755
--- a/t/t5400-send-pack.sh
+++ b/t/t5400-send-pack.sh

@@ -145,7 +145,7 @@ test_expect_success 'push --all excludes remote-tracking hierarchy' '
 	)
 '
 
-test_expect_failure 'receive-pack runs auto-gc in remote repo' '
+test_expect_success 'receive-pack runs auto-gc in remote repo' '
 	rm -rf parent child &&
 	git init parent &&
 	(

-- 
1.7.12.rc1.93.g8914ab8