pack-objects: remove bogus comment

The comment was introduced in b5d97e6 (pack-objects: run rev-list
equivalent internally. - 2006-09-04), stating that

git pack-objects [options] base-name <refs...>

is acceptable and refs should be passed into rev-list. But that's not
true. All arguments after base-name are ignored.

Remove the comment and reject this syntax (i.e. no more arguments after
base name)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/pack-objects.c

@@ -2484,23 +2484,10 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 		usage(pack_usage);
 	}
 
-	/* Traditionally "pack-objects [options] base extra" failed;
-	 * we would however want to take refs parameter that would
-	 * have been given to upstream rev-list ourselves, which means
-	 * we somehow want to say what the base name is.  So the
-	 * syntax would be:
-	 *
-	 * pack-objects [options] base <refs...>
-	 *
-	 * in other words, we would treat the first non-option as the
-	 * base_name and send everything else to the internal revision
-	 * walker.
-	 */
-
 	if (!pack_to_stdout)
 		base_name = argv[i++];
 
-	if (pack_to_stdout != !base_name)
+	if (pack_to_stdout != !base_name || argv[i])
 		usage(pack_usage);
 
 	if (!pack_to_stdout && !pack_size_limit)

t/t5300-pack-object.sh

@@ -38,6 +38,10 @@ test_expect_success \
     'pack without delta' \
     'packname_1=$(git pack-objects --window=0 test-1 <obj-list)'
 
+test_expect_success \
+    'pack-objects with bogus arguments' \
+    'test_must_fail git pack-objects --window=0 test-1 blah blah <obj-list'
+
 rm -fr .git2
 mkdir .git2