Fix concurrency bug in DefaultSerializer configuration

src/HybridDb.Tests/DocumentSessionTests.cs

@@ -3,6 +3,7 @@
 using System.Linq;
 using System.Reflection;
 using System.Text;
+using System.Threading.Tasks;
 using FakeItEasy;
 using HybridDb.Commands;
 using HybridDb.Config;
@@ -23,6 +24,33 @@ public class DocumentSessionTests : HybridDbTests
     {
         public DocumentSessionTests(ITestOutputHelper output) : base(output) { }
 
+        [Fact]
+        public async Task MultipleConcurrentReadsWhileSaving()
+        {
+            UseDefaultSerializer().EnableAutomaticBackReferences();
+
+            Document<OtherEntity>().With(x => x.Number);
+
+            var task1 = new Task(() =>
+            {
+                using var session = store.OpenSession();
+                session.Store(new OtherEntity() { Id = "a" });
+                session.SaveChanges();
+            });
+
+            var task2 = new Task(() =>
+            {
+                using var session = store.OpenSession();
+                session.Store(new OtherEntity() { Id = "b" });
+                session.SaveChanges();
+            });
+
+            task1.Start();
+            task2.Start();
+
+            await Task.WhenAll(task1, task2);
+        }
+
         [Fact]
         public void CanEvictEntity()
         {

src/HybridDb/DocumentStore.cs

@@ -83,7 +83,7 @@ public void Dispose()
         public ILogger Logger { get;  }
         public Configuration Configuration { get; }
         public TableMode TableMode { get; }
-        public StoreStats Stats { get; } = new StoreStats();
+        public StoreStats Stats { get; } = new();
         public DocumentMigrationRunner DocumentMigrationRunner { get; }
 
         public bool IsInitialized { get; private set; }

src/HybridDb/DocumentTransaction.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using Microsoft.Data.SqlClient;
 using System.Diagnostics;
@@ -286,7 +286,7 @@ public Row(T data, RowExtras extras)
             public byte[] RowVersion { get; set; }
         }
 
-        static readonly HashSet<Type> simpleTypes = new HashSet<Type>
+        static readonly HashSet<Type> simpleTypes = new()
         {
             typeof(byte),
             typeof(sbyte),

src/HybridDb/Events/Commit.cs

@@ -19,10 +19,10 @@ protected Commit(Guid id, int generation, long begin, long end)
         public long Begin { get; }
         public long End { get; }
 
-        public static Commit<T> Create<T>(Guid id, int generation, long end, IReadOnlyList<EventData<T>> events) => 
-            new Commit<T>(id, generation, end + 1 - events.Count, end, events);
+        public static Commit<T> Create<T>(Guid id, int generation, long end, IReadOnlyList<EventData<T>> events) =>
+            new(id, generation, end + 1 - events.Count, end, events);
 
-        public static Commit<T> Empty<T>() => new Commit<T>(Guid.Empty, 0, -1, -1);
+        public static Commit<T> Empty<T>() => new(Guid.Empty, 0, -1, -1);
     }
 
     public class Commit<T> : Commit
@@ -34,7 +34,7 @@ public Commit(Guid id, int generation, long begin, long end, IReadOnlyList<Event
             : base(id, generation, begin, end) => Events = events;
 
         public Commit<TOut> Map<TOut>(Func<EventData<T>, IEnumerable<EventData<TOut>>> selector) =>
-            new Commit<TOut>(Id, Generation, Begin, End, Events.SelectMany(selector).ToList());
+            new(Id, Generation, Begin, End, Events.SelectMany(selector).ToList());
 
         public IReadOnlyList<EventData<T>> Events { get; }
     }

src/HybridDb/Events/EventData.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 
 namespace HybridDb.Events
 {
@@ -37,13 +37,13 @@ public EventData(string streamId, Guid eventId, string name, long sequenceNumber
         public IReadOnlyMetadata Metadata { get; }
         public T Data { get; }
 
-        public EventData<T> WithSeq(long seq) => new EventData<T>(StreamId, EventId, Name, seq, Metadata, Data);
-        public EventData<T> WithName(string name) => new EventData<T>(StreamId, EventId, name, SequenceNumber, Metadata, Data);
-        public EventData<T> WithMetadataKey(string key, string value) => new EventData<T>(StreamId, EventId, Name, SequenceNumber, new Metadata(Metadata) { [key] = value }, Data);
-        public EventData<T> WithoutMetadataKey(string key) => new EventData<T>(StreamId, EventId, Name, SequenceNumber, new Metadata(Metadata, key), Data);
-        public EventData<T> WithStreamId(string streamId) => new EventData<T>(streamId, EventId, Name, SequenceNumber, Metadata, Data);
-        public EventData<T> WithEventId(Guid eventId) => new EventData<T>(StreamId, eventId, Name, SequenceNumber, Metadata, Data);
+        public EventData<T> WithSeq(long seq) => new(StreamId, EventId, Name, seq, Metadata, Data);
+        public EventData<T> WithName(string name) => new(StreamId, EventId, name, SequenceNumber, Metadata, Data);
+        public EventData<T> WithMetadataKey(string key, string value) => new(StreamId, EventId, Name, SequenceNumber, new Metadata(Metadata) { [key] = value }, Data);
+        public EventData<T> WithoutMetadataKey(string key) => new(StreamId, EventId, Name, SequenceNumber, new Metadata(Metadata, key), Data);
+        public EventData<T> WithStreamId(string streamId) => new(streamId, EventId, Name, SequenceNumber, Metadata, Data);
+        public EventData<T> WithEventId(Guid eventId) => new(StreamId, eventId, Name, SequenceNumber, Metadata, Data);
 
-        public EventData<TData> WithData<TData>(TData data) => new EventData<TData>(StreamId, EventId, Name, SequenceNumber, Metadata, data);
+        public EventData<TData> WithData<TData>(TData data) => new(StreamId, EventId, Name, SequenceNumber, Metadata, data);
     }
 }

src/HybridDb/Events/Metadata.cs

@@ -6,9 +6,9 @@ namespace HybridDb.Events
 {
     public class Metadata : IReadOnlyMetadata
     {
-        static readonly HashSet<string> builtInKeys = new HashSet<string>();
+        static readonly HashSet<string> builtInKeys = new();
 
-        readonly Dictionary<string, string> values = new Dictionary<string, string>();
+        readonly Dictionary<string, string> values = new();
 
         /// <summary>
         /// Unique identifier for the event.

src/HybridDb/Events/Row.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using Newtonsoft.Json;
 
@@ -17,7 +17,7 @@ public class Row
         public byte[] Data { get; set; }
 
         public static EventData<byte[]> ToEvent(Row row) =>
-            new EventData<byte[]>(row.StreamId, row.EventId, row.Name, row.SequenceNumber,
+            new(row.StreamId, row.EventId, row.Name, row.SequenceNumber,
                 new Metadata(JsonConvert.DeserializeObject<Dictionary<string, string>>(row.Metadata)), row.Data);
     }
 }

src/HybridDb/Linq/CompilerBuilder.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Linq.Expressions;
@@ -38,14 +38,12 @@ public static (Compiler compile, Emitter emit) ComposeFrontendAndBackend(Func<Ex
             }, new Emitter(emitter));
         }
 
-        public static Compiler Compose(params Func<Expression, Compiler, Compiler, BonsaiExpression>[] steps) =>
-            new Compiler(Compose(steps.Select(Convert)));
+        public static Compiler Compose(params Func<Expression, Compiler, Compiler, BonsaiExpression>[] steps) => new(Compose(steps.Select(Convert)));
 
         public static PostProcessor Compose(params Func<BonsaiExpression, PostProcessor, PostProcessor, BonsaiExpression>[] steps) =>
-            new PostProcessor(Compose(steps.Select(Convert)));
+            new(Compose(steps.Select(Convert)));
 
-        public static Emitter Compose(params Func<BonsaiExpression, Emitter, Emitter, string>[] steps) =>
-            new Emitter(Compose(steps.Select(Convert)));
+        public static Emitter Compose(params Func<BonsaiExpression, Emitter, Emitter, string>[] steps) => new(Compose(steps.Select(Convert)));
 
         static Func<TIn, TOut> Compose<TIn, TOut>(IEnumerable<Func<TIn, Func<TIn, TOut>, Func<TIn, TOut>, TOut>> steps)
         {

src/HybridDb/Migrations/Schema/SchemaMigrationRunner.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Data;
 using System.Diagnostics;
@@ -14,7 +14,7 @@ namespace HybridDb.Migrations.Schema
 {
     public class SchemaMigrationRunner
     {
-        static object locker = new object();
+        static object locker = new();
 
         readonly ILogger logger;
         readonly DocumentStore store;
@@ -82,7 +82,7 @@ void Migrate(bool isTempTables, Action action)
         }
 
         static TransactionScope BeginTransaction() => 
-            new TransactionScope(
+            new(
                 TransactionScopeOption.RequiresNew, 
                 new TransactionOptions
                 {

src/HybridDb/ObjectToDictionaryRegistry.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
@@ -12,8 +12,8 @@ namespace HybridDb
     /// </summary>
     public class ObjectToDictionaryRegistry
     {
-        private static readonly Dictionary<Type, Func<object, IDictionary<string, object>>> cache = new Dictionary<Type, Func<object, IDictionary<string, object>>>();
-        private static readonly ReaderWriterLockSlim rwLock = new ReaderWriterLockSlim();
+        private static readonly Dictionary<Type, Func<object, IDictionary<string, object>>> cache = new();
+        private static readonly ReaderWriterLockSlim rwLock = new();
 
         /// <summary>
         /// Loads the values of an object's properties into a <see cref="IDictionary{String,Object}"/>.

src/HybridDb/Queue/MessageQueueOptions.cs

@@ -8,7 +8,7 @@ namespace HybridDb.Queue
 {
     public class MessageQueueOptions
     {
-        public Version Version { get; set; } = new Version(1, 0);
+        public Version Version { get; set; } = new(1, 0);
         public TimeSpan IdleDelay { get; set; } = TimeSpan.FromMilliseconds(100);
         public TimeSpan ExceptionBackoff { get; set; } = TimeSpan.FromSeconds(15);
         public TimeSpan ConnectionTimeout { get; set; } = TimeSpan.FromSeconds(1);