Merge pull request #19027 from peppy/realm-nested-writes

Add nested transaction handling to realm helper methods

osu.Game.Tests/Database/RealmLiveTests.cs

@@ -59,6 +59,64 @@ namespace osu.Game.Tests.Database
             });
         }
 
+        [Test]
+        public void TestFailedWritePerformsRollback()
+        {
+            RunTestWithRealm((realm, _) =>
+            {
+                Assert.Throws<InvalidOperationException>(() =>
+                {
+                    realm.Write(r =>
+                    {
+                        r.Add(new BeatmapInfo(CreateRuleset(), new BeatmapDifficulty(), new BeatmapMetadata()));
+                        throw new InvalidOperationException();
+                    });
+                });
+
+                Assert.That(realm.Run(r => r.All<BeatmapInfo>()), Is.Empty);
+            });
+        }
+
+        [Test]
+        public void TestFailedNestedWritePerformsRollback()
+        {
+            RunTestWithRealm((realm, _) =>
+            {
+                Assert.Throws<InvalidOperationException>(() =>
+                {
+                    realm.Write(r =>
+                    {
+                        realm.Write(_ =>
+                        {
+                            r.Add(new BeatmapInfo(CreateRuleset(), new BeatmapDifficulty(), new BeatmapMetadata()));
+                            throw new InvalidOperationException();
+                        });
+                    });
+                });
+
+                Assert.That(realm.Run(r => r.All<BeatmapInfo>()), Is.Empty);
+            });
+        }
+
+        [Test]
+        public void TestNestedWriteCalls()
+        {
+            RunTestWithRealm((realm, _) =>
+            {
+                var beatmap = new BeatmapInfo(CreateRuleset(), new BeatmapDifficulty(), new BeatmapMetadata());
+
+                var liveBeatmap = beatmap.ToLive(realm);
+
+                realm.Run(r =>
+                    r.Write(_ =>
+                        r.Write(_ =>
+                            r.Add(beatmap)))
+                );
+
+                Assert.IsFalse(liveBeatmap.PerformRead(l => l.Hidden));
+            });
+        }
+
         [Test]
         public void TestAccessAfterAttach()
         {

osu.Game/Database/RealmExtensions.cs

@@ -8,20 +8,61 @@ namespace osu.Game.Database
 {
     public static class RealmExtensions
     {
+        /// <summary>
+        /// Perform a write operation against the provided realm instance.
+        /// </summary>
+        /// <remarks>
+        /// This will automatically start a transaction if not already in one.
+        /// </remarks>
+        /// <param name="realm">The realm to operate on.</param>
+        /// <param name="function">The write operation to run.</param>
         public static void Write(this Realm realm, Action<Realm> function)
         {
-            using var transaction = realm.BeginWrite();
+            Transaction? transaction = null;
+
+            try
+            {
+                if (!realm.IsInTransaction)
+                    transaction = realm.BeginWrite();
+
                 function(realm);
-            transaction.Commit();
+
+                transaction?.Commit();
+            }
+            finally
+            {
+                transaction?.Dispose();
+            }
         }
 
+        /// <summary>
+        /// Perform a write operation against the provided realm instance.
+        /// </summary>
+        /// <remarks>
+        /// This will automatically start a transaction if not already in one.
+        /// </remarks>
+        /// <param name="realm">The realm to operate on.</param>
+        /// <param name="function">The write operation to run.</param>
         public static T Write<T>(this Realm realm, Func<Realm, T> function)
         {
-            using var transaction = realm.BeginWrite();
+            Transaction? transaction = null;
+
+            try
+            {
+                if (!realm.IsInTransaction)
+                    transaction = realm.BeginWrite();
+
                 var result = function(realm);
-            transaction.Commit();
+
+                transaction?.Commit();
+
                 return result;
             }
+            finally
+            {
+                transaction?.Dispose();
+            }
+        }
 
         /// <summary>
         /// Whether the provided change set has changes to the top level collection.