From 2647811a134a972cc8f7cb5ba89a7d8ef48b724d Mon Sep 17 00:00:00 2001
From: penev92 <penev92@gmail.com>
Date: Fri, 12 Jun 2015 14:20:26 +0300
Subject: [PATCH] Add UpgradeUsedReferenceAttribute

---
 OpenRA.Game/Traits/LintAttributes.cs                  | 3 +++
 OpenRA.Mods.Common/Traits/Upgrades/UpgradableTrait.cs | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/OpenRA.Game/Traits/LintAttributes.cs b/OpenRA.Game/Traits/LintAttributes.cs
index 005ad50c31..9c5c9cc209 100644
--- a/OpenRA.Game/Traits/LintAttributes.cs
+++ b/OpenRA.Game/Traits/LintAttributes.cs
@@ -40,4 +40,7 @@ namespace OpenRA.Traits
 
 	[AttributeUsage(AttributeTargets.Field)]
 	public sealed class UpgradeGrantedReferenceAttribute : Attribute { }
+
+	[AttributeUsage(AttributeTargets.Field)]
+	public sealed class UpgradeUsedReferenceAttribute : Attribute { }
 }
diff --git a/OpenRA.Mods.Common/Traits/Upgrades/UpgradableTrait.cs b/OpenRA.Mods.Common/Traits/Upgrades/UpgradableTrait.cs
index 536b15e49a..06e2d4044d 100644
--- a/OpenRA.Mods.Common/Traits/Upgrades/UpgradableTrait.cs
+++ b/OpenRA.Mods.Common/Traits/Upgrades/UpgradableTrait.cs
@@ -7,6 +7,7 @@
  * see COPYING.
  */
 #endregion
+
 using System.Collections.Generic;
 using System.Linq;
 using OpenRA.Traits;
@@ -16,6 +17,7 @@ namespace OpenRA.Mods.Common.Traits
 	/// <summary>Use as base class for *Info to subclass of UpgradableTrait. (See UpgradableTrait.)</summary>
 	public abstract class UpgradableTraitInfo
 	{
+		[UpgradeUsedReference]
 		[Desc("The upgrade types which can enable or disable this trait.")]
 		public readonly string[] UpgradeTypes = { };