diff --git a/OpenRA.Game/GameRules/ActorInfo.cs b/OpenRA.Game/GameRules/ActorInfo.cs
index cce7eb280e..e721634d7c 100644
--- a/OpenRA.Game/GameRules/ActorInfo.cs
+++ b/OpenRA.Game/GameRules/ActorInfo.cs
@@ -100,7 +100,7 @@ namespace OpenRA
 			var unresolved = source.Except(resolved);
 
 			var testResolve = new Func<Type, Type, bool>((a, b) => a == b || a.IsAssignableFrom(b));
-			var more = unresolved.Where(u => u.Dependencies.All(d => resolved.Exists(r => testResolve(d, r.Type))));
+			var more = unresolved.Where(u => u.Dependencies.All(d => resolved.Exists(r => testResolve(d, r.Type)) && !unresolved.Any(u1 => testResolve(d, u1.Type))));
 
 			// Re-evaluate the vars above until sorted
 			while (more.Any())
@@ -122,14 +122,14 @@ namespace OpenRA
 					exceptionString += u.Type + ": { " + string.Join(", ", deps) + " }\r\n";
 				}
 
-				throw new Exception(exceptionString);
+				throw new YamlException(exceptionString);
 			}
 
 			constructOrderCache = resolved.Select(r => r.Trait).ToList();
 			return constructOrderCache;
 		}
 
-		static IEnumerable<Type> PrerequisitesOf(ITraitInfo info)
+		public static IEnumerable<Type> PrerequisitesOf(ITraitInfo info)
 		{
 			return info
 				.GetType()
diff --git a/OpenRA.Test/OpenRA.Game/ActorInfoTest.cs b/OpenRA.Test/OpenRA.Game/ActorInfoTest.cs
index 5d09ad3f65..b3219869e3 100644
--- a/OpenRA.Test/OpenRA.Game/ActorInfoTest.cs
+++ b/OpenRA.Test/OpenRA.Game/ActorInfoTest.cs
@@ -10,7 +10,6 @@
 #endregion
 
 using System;
-using System.Collections.Generic;
 using System.Linq;
 using System.Text.RegularExpressions;
 using NUnit.Framework;
@@ -34,20 +33,26 @@ namespace OpenRA.Test
 		[TestCase(TestName = "Trait ordering sorts in dependency order correctly")]
 		public void TraitOrderingSortsCorrectly()
 		{
-			var actorInfo = new ActorInfo("test", new MockCInfo(), new MockBInfo(), new MockAInfo());
+			var unorderedTraits = new ITraitInfo[] { new MockBInfo(), new MockCInfo(), new MockAInfo(), new MockBInfo() };
+			var actorInfo = new ActorInfo("test", unorderedTraits);
+			var orderedTraits = actorInfo.TraitsInConstructOrder().ToArray();
 
-			var i = new List<ITraitInfo>(actorInfo.TraitsInConstructOrder());
+			CollectionAssert.AreEquivalent(unorderedTraits, orderedTraits);
 
-			Assert.That(i[0], Is.InstanceOf<MockAInfo>());
-			Assert.That(i[1].GetType().Name, Is.EqualTo("MockBInfo"));
-			Assert.That(i[2].GetType().Name, Is.EqualTo("MockCInfo"));
+			for (var i = 0; i < orderedTraits.Length; i++)
+			{
+				var traitTypesThatMustOccurBeforeThisTrait = ActorInfo.PrerequisitesOf(orderedTraits[i]);
+				var traitTypesThatOccurAfterThisTrait = orderedTraits.Skip(i + 1).Select(ti => ti.GetType());
+				var traitTypesThatShouldOccurEarlier = traitTypesThatOccurAfterThisTrait.Intersect(traitTypesThatMustOccurBeforeThisTrait);
+				CollectionAssert.IsEmpty(traitTypesThatShouldOccurEarlier, "Dependency order has not been satisfied.");
+			}
 		}
 
 		[TestCase(TestName = "Trait ordering exception reports missing dependencies")]
 		public void TraitOrderingReportsMissingDependencies()
 		{
 			var actorInfo = new ActorInfo("test", new MockBInfo(), new MockCInfo());
-			var ex = Assert.Throws<Exception>(() => actorInfo.TraitsInConstructOrder());
+			var ex = Assert.Throws<YamlException>(() => actorInfo.TraitsInConstructOrder());
 
 			StringAssert.Contains(typeof(MockAInfo).Name, ex.Message, "Exception message did not report a missing dependency.");
 			StringAssert.Contains(typeof(MockBInfo).Name, ex.Message, "Exception message did not report a missing dependency.");
@@ -60,7 +65,7 @@ namespace OpenRA.Test
 		public void TraitOrderingReportsCyclicDependencies()
 		{
 			var actorInfo = new ActorInfo("test", new MockDInfo(), new MockEInfo(), new MockFInfo());
-			var ex = Assert.Throws<Exception>(() => actorInfo.TraitsInConstructOrder());
+			var ex = Assert.Throws<YamlException>(() => actorInfo.TraitsInConstructOrder());
 
 			StringAssert.Contains(typeof(MockDInfo).Name, ex.Message, "Exception message should report all cyclic dependencies.");
 			StringAssert.Contains(typeof(MockEInfo).Name, ex.Message, "Exception message should report all cyclic dependencies.");