From: David Kastrup <dak@gnu.org>
Date: Sat, 16 Mar 2013 10:22:27 +0000 (+0100)
Subject: Issue 3247: Prohibit non-postevents returned by music functions to be used as post... 
X-Git-Tag: release/2.17.15-1~17^2~16
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=be1247a9a2f9884f4c6b92bb6b637917a544a951;p=lilypond.git

Issue 3247: Prohibit non-postevents returned by music functions to be used as post-events

For example,

{ c-\mark \default }

produced an invalid music expression more or less indistinguishable from

{ \mark \default c }

Worse is that things like

{ c-\tweak color #red { g } }

also got accepted.  While \tweak (and other music functions) may
indeed return either post-events or straight music expressions, there
should be checks in place that the usage corresponds to its type.
---

diff --git a/lily/parser.yy b/lily/parser.yy
index 0197fe9d93..79560ab1d7 100644
--- a/lily/parser.yy
+++ b/lily/parser.yy
@@ -2490,8 +2490,10 @@ post_events:
 		$$ = SCM_EOL;
 	}
 	| post_events post_event {
-		unsmob_music ($2)->set_spot (@2);
-		$$ = scm_cons ($2, $$);
+		if (unsmob_music ($2)) {
+			unsmob_music ($2)->set_spot (@2);
+			$$ = scm_cons ($2, $$);
+		}
 	}
 	;
 
@@ -2501,7 +2503,10 @@ post_event_nofinger:
 	}
 	| script_dir music_function_call_closed {
 		$$ = $2;
-		if (!SCM_UNBNDP ($1))
+		if (!unsmob_music ($2)->is_mus_type ("post-event")) {
+			parser->parser_error (@2, _ ("post-event expected"));
+			$$ = SCM_UNSPECIFIED;
+		} else if (!SCM_UNBNDP ($1))
 		{
 			unsmob_music ($$)->set_property ("direction", $1);
 		}