Add two more update rules

OpenRA.Mods.Common/UpdateRules/Rules/AircraftCanHoverGeneralization.cs

@@ -0,0 +1,48 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2018 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System.Collections.Generic;
+using System.Linq;
+
+namespace OpenRA.Mods.Common.UpdateRules.Rules
+{
+	public class AircraftCanHoverGeneralization : UpdateRule
+	{
+		public override string Name { get { return "Split Aircraft.CanHover into multiple parameters"; } }
+		public override string Description
+		{
+			get
+			{
+				return "Aircraft VTOL behaviour has been moved from CanHover to a new VTOL parameter.\n" +
+					"Aircraft taking off automatically after reloading has been moved from CanHover to a new TakeOffOnResupply parameter.\n" +
+					"Actors that set CanHover: true are updated with appropriate defaults for these parameters.";
+			}
+		}
+
+		public override IEnumerable<string> UpdateActorNode(ModData modData, MiniYamlNode actorNode)
+		{
+			foreach (var aircraft in actorNode.ChildrenMatching("Aircraft"))
+			{
+				var canHover = aircraft.LastChildMatching("CanHover");
+				if (canHover != null && canHover.NodeValue<bool>())
+				{
+					if (!aircraft.ChildrenMatching("TakeOffOnResupply").Any())
+						aircraft.AddNode("TakeOffOnResupply", true);
+
+					if (!aircraft.ChildrenMatching("VTOL").Any())
+						aircraft.AddNode("VTOL", true);
+				}
+			}
+
+			yield break;
+		}
+	}
+}