Properly update Solo state when setting multiple ctrls

libs/ardour/session.cc

@@ -5688,6 +5688,15 @@ Session::setup_lua ()
 	LuaBindings::stddef (L);
 	LuaBindings::common (L);
 	LuaBindings::dsp (L);
+	luabridge::getGlobalNamespace (L)
+		.beginNamespace ("Ardour")
+		.beginClass <Session> ("Session")
+		/* thse are private to Session */
+		.addFunction ("rt_set_controls", &Session::rt_set_controls)
+		.addFunction ("rt_clear_all_solo_state", &Session::rt_clear_all_solo_state)
+		.endClass ()
+		.endNamespace ();
+
 	lua_mlock (L, 0);
 	luabridge::push <Session *> (L, this);
 	lua_setglobal (L, "Session");

libs/ardour/session_rtevents.cc

@@ -104,13 +104,13 @@ Session::rt_set_controls (std::shared_ptr<WeakAutomationControlList> cl, double
 		return;
 	}
 
-	AutomationType type = NullAutomation;
+	bool update_solo_state = false;
 
 	for (auto const& c : *cl) {
 		std::shared_ptr<AutomationControl> ac = c.lock ();
 		if (ac) {
 			ac->set_value (val, gcd);
-			type = ac->desc().type;
+			update_solo_state |= SoloAutomation == ac->desc().type;
 		}
 	}
 
@@ -118,12 +118,8 @@ Session::rt_set_controls (std::shared_ptr<WeakAutomationControlList> cl, double
 	 * that here.
 	 */
 
-	switch (type) {
-	case SoloAutomation:
+	if (update_solo_state) {
 		update_route_solo_state ();
-		break;
-	default:
-		break;
 	}
 }