[PATCH] shortlog: prompt when reading from terminal by mistake

From: Junio C Hamano <junkio@cox.net>
Date: Mar 8, 2007, 10:12 UTC
Message-ID: <7vhcsw9h8p.fsf@assigned-by-dhcp.cox.net>

I was trying to see who have been active recently to find GSoC mentor candidates by running:

	$ git shortlog -s -n --since=4.months | head -n 20

After waiting for about 20 seconds, I started getting worried, thinking that the recent revision traversal updates might have had an unintended side effect.

Not so. "git shortlog" acts as a filter when no revs are given, unlike "git log" which defaults to HEAD. It was reading from its standard input.

Signed-off-by: Junio C Hamano <junkio@cox.net>
---

   Arguably because --since=4.months clearly states I am
   expecting it to start digging from somewhere, it would be
   more sensible to default to HEAD in this case.  I suspect it
   might be as simple as checking argc before we call
   setup_revisions() and pass "HEAD" as the default parameter to
   it, but it is getting late here.

 builtin-shortlog.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/builtin-shortlog.c b/builtin-shortlog.c
index 2d7726e..29343ae 100644
--- a/builtin-shortlog.c
+++ b/builtin-shortlog.c
@@ -304,8 +304,11 @@ int cmd_shortlog(int argc, const char **argv, const char *prefix)
 	if (!access(".mailmap", R_OK))
 		read_mailmap(".mailmap");
 
-	if (rev.pending.nr == 0)
+	if (rev.pending.nr == 0) {
+		if (isatty(0))
+			fprintf(stderr, "(reading log to summarize from standard input)\n");
 		read_from_stdin(&list);
+	}
 	else
 		get_from_rev(&rev, &list);