Revert 444a028, 0e5a469 and 9d8f33e

src/Umbraco.Core/Cache/HttpRequestCacheProvider.cs

@@ -2,7 +2,6 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading;
 using System.Web;
 
 namespace Umbraco.Core.Cache
@@ -106,7 +105,7 @@ namespace Umbraco.Core.Cache
                 
                 if (result == null || GetSafeLazyValue(result, true) == null) // get non-created as NonCreatedValue & exceptions as null
                 {
-                    result = new Lazy<object>(getCacheItem, LazyThreadSafetyMode.PublicationOnly);
+                    result = new Lazy<object>(getCacheItem);
                     ContextItems[cacheKey] = result;
                 }
             }

src/Umbraco.Core/Cache/HttpRuntimeCacheProvider.cs

@@ -129,17 +129,11 @@ namespace Umbraco.Core.Cache
 
                 if (result == null || GetSafeLazyValue(result, true) == null) // get non-created as NonCreatedValue & exceptions as null
                 {
+                    result = new Lazy<object>(getCacheItem);
                     var absolute = isSliding ? System.Web.Caching.Cache.NoAbsoluteExpiration : (timeout == null ? System.Web.Caching.Cache.NoAbsoluteExpiration : DateTime.Now.Add(timeout.Value));
                     var sliding = isSliding == false ? System.Web.Caching.Cache.NoSlidingExpiration : (timeout ?? System.Web.Caching.Cache.NoSlidingExpiration);
 
                     lck.UpgradeToWriteLock();
-
-                    result = new Lazy<object>(getCacheItem,
-                        //NOTE: This is required to not cache any exceptions that throw when the callback is executed.
-                        // we want to ensure the callback is re-executed and not cached in the case that it might no
-                        // longer throw an exception if runtime circumstances have changed.
-                        LazyThreadSafetyMode.PublicationOnly);
-                    
                     _cache.Insert(cacheKey, result, dependency, absolute, sliding, priority, removedCallback);
                 }
             }
@@ -179,12 +173,7 @@ namespace Umbraco.Core.Cache
             // NOTE - here also we must insert a Lazy<object> but we can evaluate it right now
             // and make sure we don't store a null value.
 
-            var result = new Lazy<object>(getCacheItem,
-                //NOTE: This is required to not cache any exceptions that throw when the callback is executed.
-                // we want to ensure the callback is re-executed and not cached in the case that it might no
-                // longer throw an exception if runtime circumstances have changed.
-                LazyThreadSafetyMode.PublicationOnly);
-
+            var result = new Lazy<object>(getCacheItem);
             var value = result.Value; // force evaluation now - this may throw if cacheItem throws, and then nothing goes into cache
             if (value == null) return; // do not store null values (backward compat)
 

src/Umbraco.Core/Cache/ObjectCacheRuntimeCacheProvider.cs

@@ -207,14 +207,10 @@ namespace Umbraco.Core.Cache
                 result = MemoryCache.Get(cacheKey) as Lazy<object>;
                 if (result == null || GetSafeLazyValue(result, true) == null) // get non-created as NonCreatedValue & exceptions as null
                 {
+                    result = new Lazy<object>(getCacheItem);
                     var policy = GetPolicy(timeout, isSliding, removedCallback, dependentFiles);
 
                     lck.UpgradeToWriteLock();
-                    result = new Lazy<object>(getCacheItem, 
-                        //NOTE: This is required to not cache any exceptions that throw when the callback is executed.
-                        // we want to ensure the callback is re-executed and not cached in the case that it might no
-                        // longer throw an exception if runtime circumstances have changed.
-                        LazyThreadSafetyMode.PublicationOnly);
                     MemoryCache.Set(cacheKey, result, policy);
                 }
             }
@@ -231,11 +227,7 @@ namespace Umbraco.Core.Cache
             // NOTE - here also we must insert a Lazy<object> but we can evaluate it right now
             // and make sure we don't store a null value.
 
-            var result = new Lazy<object>(getCacheItem,
-                //NOTE: This is required to not cache any exceptions that throw when the callback is executed.
-                // we want to ensure the callback is re-executed and not cached in the case that it might no
-                // longer throw an exception if runtime circumstances have changed.
-                LazyThreadSafetyMode.PublicationOnly);
+            var result = new Lazy<object>(getCacheItem);
             var value = result.Value; // force evaluation now
             if (value == null) return; // do not store null values (backward compat)
 

src/Umbraco.Tests/Cache/CacheProviderTests.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Linq;
+using System.Linq;
 using System.Web.UI;
 using NUnit.Framework;
 using Umbraco.Core.Cache;
@@ -24,59 +23,6 @@ namespace Umbraco.Tests.Cache
             Provider.ClearAllCache();
         }
 
-        [Test]
-        public void Does_Not_Cache_Exceptions()
-        {
-            var counter = 0;
-
-            object result;
-            try
-            {
-                result = Provider.GetCacheItem("Blah", () =>
-                    {
-                        counter++;
-                        throw new Exception("Do not cache this");
-                    });
-            }
-            catch (Exception){}
-
-            try
-            {
-                result = Provider.GetCacheItem("Blah", () =>
-                {
-                    counter++;
-                    throw new Exception("Do not cache this");
-                });
-            }
-            catch (Exception){}
-
-            Assert.Greater(counter, 1);
-
-        }
-
-        [Test]
-        public void Ensures_Delegate_Result_Is_Cached_Once()
-        {
-            var counter = 0;
-
-            object result;
-            
-            result = Provider.GetCacheItem("Blah", () =>
-            {
-                counter++;
-                return "";
-            });
-
-            result = Provider.GetCacheItem("Blah", () =>
-            {
-                counter++;
-                return "";
-            });
-
-            Assert.AreEqual(counter, 1);
-
-        }
-
         [Test]
         public void Can_Get_By_Search()
         {