Fixes unit tests using the ContentService.Save method. Because we are using .ToXml in the save method to save preview xml we need to setup the DataTypesResolver in the test setup.

src/Umbraco.Tests/Persistence/Repositories/RelationRepositoryTest.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Linq;
 using NUnit.Framework;
+using Umbraco.Core;
 using Umbraco.Core.Models;
 using Umbraco.Core.Persistence.Caching;
 using Umbraco.Core.Persistence.Querying;
@@ -8,6 +9,8 @@ using Umbraco.Core.Persistence.Repositories;
 using Umbraco.Core.Persistence.UnitOfWork;
 using Umbraco.Tests.TestHelpers;
 using Umbraco.Tests.TestHelpers.Entities;
+using umbraco.editorControls.tinyMCE3;
+using umbraco.interfaces;
 
 namespace Umbraco.Tests.Persistence.Repositories
 {
@@ -17,6 +20,20 @@ namespace Umbraco.Tests.Persistence.Repositories
         [SetUp]
         public override void Initialize()
         {
+            //NOTE The DataTypesResolver is only necessary because we are using the Save method in the ContentService
+            //this ensures its reset
+            PluginManager.Current = new PluginManager();
+
+            //for testing, we'll specify which assemblies are scanned for the PluginTypeResolver
+            PluginManager.Current.AssembliesToScan = new[]
+				{
+                    typeof(IDataType).Assembly,
+                    typeof(tinyMCE3dataType).Assembly
+				};
+
+            DataTypesResolver.Current = new DataTypesResolver(
+                PluginManager.Current.ResolveDataTypes());
+
             base.Initialize();
 
             CreateTestData();
@@ -237,6 +254,9 @@ namespace Umbraco.Tests.Persistence.Repositories
         [TearDown]
         public override void TearDown()
         {
+            //reset the app context
+            DataTypesResolver.Reset();
+
             base.TearDown();
         }