setup_revisions(): do not call get_pathspec() too early

This is necessary because we will later allow pathspecs to be fed from the
standard input, and pathspecs taken from the command line (and converted
via get_pathspec() already) in revs->prune_data too early gets in the way
when we want to append from the standard input.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/revision.c b/revision.c
index f5b735f..4410a45 100644
--- a/revision.c
+++ b/revision.c
@@ -1230,6 +1230,7 @@
 int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def)
 {
 	int i, flags, left, seen_dashdash, read_from_stdin;
+	const char **prune_data = NULL;
 
 	/* First, search for "--" */
 	seen_dashdash = 0;
@@ -1240,7 +1241,7 @@
 		argv[i] = NULL;
 		argc = i;
 		if (argv[i + 1])
-			revs->prune_data = get_pathspec(revs->prefix, argv + i + 1);
+			prune_data = argv + i + 1;
 		seen_dashdash = 1;
 		break;
 	}
@@ -1321,12 +1322,14 @@
 			for (j = i; j < argc; j++)
 				verify_filename(revs->prefix, argv[j]);
 
-			revs->prune_data = get_pathspec(revs->prefix,
-							argv + i);
+			prune_data = argv + i;
 			break;
 		}
 	}
 
+	if (prune_data)
+		revs->prune_data = get_pathspec(revs->prefix, prune_data);
+
 	if (revs->def == NULL)
 		revs->def = def;
 	if (revs->show_merge)