net5 compilation and delete obsolete code

Containers/do-sqlserver2019

@@ -0,0 +1,12 @@
+FROM mcr.microsoft.com/mssql/server:2019-CU12-ubuntu-20.04
+USER root
+RUN apt-get -y update && \
+    apt-get install -yq curl apt-transport-https && \
+    apt-get install -y gnupg2 && \
+    curl https://packages.microsoft.com/keys/microsoft.asc | apt-key add - && \
+    curl https://packages.microsoft.com/config/ubuntu/20.04/mssql-server-2019.list | tee /etc/apt/sources.list.d/mssql-server.list && \
+    apt-get update && \
+    apt-get install -y mssql-server-fts && \
+    apt-get clean && \ 
+    rm -rf /var/lib/apt/lists
+USER mssql

Directory.Build.props

@@ -32,12 +32,15 @@
     <DoGeneratePackage Condition="$(MSBuildProjectName) == 'Xtensive.Orm.Manual'">false</DoGeneratePackage>
     <DoGeneratePackage Condition="$(MSBuildProjectName) == 'TestCommon'">false</DoGeneratePackage>
     <DoGeneratePackage Condition="$(MSBuildProjectName.Contains('Tests')) == 'true'">false</DoGeneratePackage>
+
+    <!-- Disable "BinaryFormatter is obsolete" warnings for test projects -->
+    <NoWarn Condition="$(MSBuildProjectName.Contains('Tests')) == 'true'">$(NoWarn);SYSLIB0011</NoWarn>
   </PropertyGroup>
 
   <PropertyGroup>
     <NoLogo>true</NoLogo>
     <SuppressNETCoreSdkPreviewMessage>true</SuppressNETCoreSdkPreviewMessage>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
     <LangVersion>9.0</LangVersion>
     <SolutionDir Condition="$(SolutionDir) == ''">$([MSBuild]::EnsureTrailingSlash(
       $([MSBuild]::GetDirectoryNameOfFileAbove('$(MSBuildThisFileDirectory)', 'Orm.sln'))))</SolutionDir>

Extensions/Xtensive.Orm.BulkOperations/Internals/SetOperation.cs

@@ -73,16 +73,18 @@ private void PreprocessStructures()
         ex = Expression.Call(
             typeof (Queryable), "Select", new[] {parameter.Type, f.ValueType}, ex, lambda);
         ex = Expression.Call(typeof (Queryable), call.Method.Name, new[] {f.ValueType}, ex);*/
-              else
-              {
+              else {
                 //ex = Expression.Convert(ex, typeof(Structure));
-                var list = new List<FieldInfo> { f };
-                while (list.Last().Parent != setDescriptor.Field)
-                  list.Add(f.Parent);
-                list.Reverse();
+                var last = f;
+                var fields = new List<FieldInfo> { last };
+                while (last.Parent != setDescriptor.Field) {
+                  last = f.Parent;
+                  fields.Add(last);
+                }
                 Expression member = ex;
-                foreach (FieldInfo f2 in list)
-                  member = Expression.MakeMemberAccess(member, f2.UnderlyingProperty);
+                for (var i = fields.Count; i-- > 0;) {
+                  member = Expression.MakeMemberAccess(member, fields[i].UnderlyingProperty);
+                }
                 ex = member;
               }
               Descriptors.Add(new SetDescriptor(f, setDescriptor.Parameter, ex));

Extensions/Xtensive.Orm.Reprocessing/ExecuteActionStrategy.cs

@@ -11,8 +11,8 @@ namespace Xtensive.Orm.Reprocessing
   /// </summary>
   public abstract class ExecuteActionStrategy : IExecuteActionStrategy
   {
-    private static readonly ConcurrentDictionary<Type, IExecuteActionStrategy> Singletons =
-      new ConcurrentDictionary<Type, IExecuteActionStrategy>();
+    private static readonly ConcurrentDictionary<Type, Lazy<IExecuteActionStrategy>> Singletons =
+      new ConcurrentDictionary<Type, Lazy<IExecuteActionStrategy>>();
 
     /// <summary>
     /// Gets singleton of the <see cref="HandleReprocessableExceptionStrategy"/>.
@@ -137,7 +137,13 @@ public static IExecuteActionStrategy GetSingleton(Type type)
       if (type == typeof(NoReprocessStrategy)) {
         return NoReprocess;
       }
-      return Singletons.GetOrAdd(type, a => (IExecuteActionStrategy) Activator.CreateInstance(type));
+
+      return Singletons.GetOrAdd(type, ActionStrategyFactory).Value;
+
+      static Lazy<IExecuteActionStrategy> ActionStrategyFactory(Type t)
+      {
+        return new Lazy<IExecuteActionStrategy>(() => (IExecuteActionStrategy) Activator.CreateInstance(t));
+      }
     }
 
     #region Non-public methods

Extensions/Xtensive.Orm.Security/Role.cs

@@ -11,7 +11,7 @@ namespace Xtensive.Orm.Security
   public abstract class Role : Entity, IRole
   {
     private List<Permission> permissions;
-    private ReadOnlyList<Permission> readOnlyPermissions;
+    private IList<Permission> readOnlyPermissions;
 
     /// <inheritdoc/>
     [NotNullConstraint(IsImmediate = true)]
@@ -57,7 +57,7 @@ protected override void OnInitialize()
     {
       base.OnInitialize();
       permissions = new List<Permission>();
-      readOnlyPermissions = new ReadOnlyList<Permission>(permissions);
+      readOnlyPermissions = permissions.AsReadOnly();
       RegisterPermissions();
     }
 

Extensions/Xtensive.Orm.Web.Tests/Xtensive.Orm.Web.Tests.csproj

@@ -1,10 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
     <IsPackable>false</IsPackable>
     <SignAssembly>true</SignAssembly>
     <AssemblyOriginatorKeyFile>$(ExtensionsKeyFile)</AssemblyOriginatorKeyFile>
+    <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
+    <GenerateTargetFrameworkAttribute>false</GenerateTargetFrameworkAttribute>
   </PropertyGroup>
   <Import Project="$(SolutionDir)MSBuild\DataObjects.Net.InternalBuild.targets" />
   <ItemGroup>

Extensions/Xtensive.Orm.Web/SessionManager.cs

@@ -75,7 +75,7 @@ public static SessionManager Demand()
     /// </summary>
     public bool HasSession
     {
-      get { return sessionAndTransactionPair.Value != null && sessionAndTransactionPair.Value.First != null; }
+      get { return sessionAndTransactionPair.Value.First != null; }
     }
 
     /// <summary>

Orm/Xtensive.Orm.Firebird/Orm.Providers.Firebird/DomainHandler.cs

@@ -13,6 +13,7 @@ namespace Xtensive.Orm.Providers.Firebird
   /// </summary>
   public class DomainHandler : Providers.DomainHandler
   {
+    /// <inheritdoc/>
     protected override ICompiler CreateCompiler(CompilerConfiguration configuration)
     {
       return new SqlCompiler(Handlers, configuration);

Orm/Xtensive.Orm.Firebird/Sql.Drivers.Firebird/DriverFactory.cs

@@ -42,6 +42,7 @@ protected override SqlDriver CreateDriver(string connectionString, SqlDriverConf
         connectionString, GetVersionFromServerVersionString(connection.ServerVersion), defaultSchema);
     }
 
+    /// <inheritdoc/>
     protected override async Task<SqlDriver> CreateDriverAsync(
       string connectionString, SqlDriverConfiguration configuration, CancellationToken token)
     {

Orm/Xtensive.Orm.Firebird/Sql.Drivers.Firebird/v2_5/ServerInfoProvider.cs

@@ -17,9 +17,6 @@ internal class ServerInfoProvider : Info.ServerInfoProvider
     // The limit is 64kB for statement text, 64kB for compiled BLR and 48kB for execution plan.
     private const int MaxTextLength = int.MaxValue;
 
-    private readonly string databaseName;
-    private readonly string defaultSchemaName;
-
     public override EntityInfo GetCollationInfo()
     {
       return null;

Orm/Xtensive.Orm.Manual/Upgrade/Model_2/Upgrader.cs

@@ -4,10 +4,7 @@
 // Created by: Alex Kofman
 // Created:    2009.11.12
 
-using System;
-using System.Diagnostics;
-using Xtensive.Collections;
-using Xtensive.Modelling.Comparison.Hints;
+using System.Collections.Generic;
 using Xtensive.Orm.Upgrade;
 
 namespace Xtensive.Orm.Manual.Upgrade.Model_2

Orm/Xtensive.Orm.Manual/Upgrade/Model_3/Upgrader.cs

@@ -4,9 +4,7 @@
 // Created by: Alex Kofman
 // Created:    2009.11.12
 
-using System;
-using Xtensive.Collections;
-using Xtensive.Modelling.Comparison.Hints;
+using System.Collections.Generic;
 using Xtensive.Orm.Upgrade;
 
 namespace Xtensive.Orm.Manual.Upgrade.Model_3

Orm/Xtensive.Orm.Manual/Upgrade/Model_4/Upgrader.cs

@@ -4,10 +4,8 @@
 // Created by: Alex Kofman
 // Created:    2009.11.19
 
-using System;
+using System.Collections.Generic;
 using System.Linq;
-using Xtensive.Collections;
-using Xtensive.Modelling.Comparison.Hints;
 using Xtensive.Orm.Upgrade;
 
 namespace Xtensive.Orm.Manual.Upgrade.Model_4

Orm/Xtensive.Orm.MySql/Orm.Providers.MySql/DomainHandler.cs

@@ -13,6 +13,7 @@ namespace Xtensive.Orm.Providers.MySql
   /// </summary>
   public class DomainHandler : Providers.DomainHandler
   {
+    /// <inheritdoc/>
     protected override ICompiler CreateCompiler(CompilerConfiguration configuration)
     {
       return new SqlCompiler(Handlers, configuration);

Orm/Xtensive.Orm.MySql/Sql.Drivers.MySql/v5_0/ServiceInfoProvider.cs

@@ -14,9 +14,6 @@ internal class ServerInfoProvider : Info.ServerInfoProvider
     private const int MaxIdentifierLength = 64;
     private const int DoNotKnow = int.MaxValue;
 
-    private readonly string databaseName;
-    private readonly string defaultSchemaName;
-
     /// <inheritdoc/>
     public override EntityInfo GetCollationInfo()
     {

Orm/Xtensive.Orm.Oracle/Orm.Providers.Oracle/DomainHandler.cs

@@ -13,6 +13,7 @@ namespace Xtensive.Orm.Providers.Oracle
   /// </summary>
   public class DomainHandler : Providers.DomainHandler
   {
+    /// <inheritdoc/>
     protected override ICompiler CreateCompiler(CompilerConfiguration configuration)
     {
       return new SqlCompiler(Handlers, configuration);

Orm/Xtensive.Orm.Oracle/Sql.Drivers.Oracle/DriverFactory.cs

@@ -34,6 +34,7 @@ private static Version ParseVersion(string version)
       return new Version(items[0], items[1], items[2], items[3]);
     }
 
+    /// <inheritdoc/>
     protected override string BuildConnectionString(UrlInfo url)
     {
       SqlHelper.ValidateConnectionUrl(url);

Orm/Xtensive.Orm.Oracle/Sql.Drivers.Oracle/v09/ServerInfoProvider.cs

@@ -15,9 +15,6 @@ internal class ServerInfoProvider : Info.ServerInfoProvider
     private const int MaxIdentifierLength = 30;
     private const int DoNotKnow = int.MaxValue;
 
-    private readonly string databaseName;
-    private readonly string defaultSchemaName;
-
     public override EntityInfo GetCollationInfo()
     {
       return null;

Orm/Xtensive.Orm.PostgreSql/Orm.Providers.PostgreSql/DomainHandler.cs

@@ -17,9 +17,11 @@ namespace Xtensive.Orm.Providers.PostgreSql
   /// </summary>
   public class DomainHandler : Providers.DomainHandler
   {
+    /// <inheritdoc/>
     protected override ICompiler CreateCompiler(CompilerConfiguration configuration) =>
       new SqlCompiler(Handlers, configuration);
 
+    /// <inheritdoc/>
     protected override IEnumerable<Type> GetProviderCompilerContainers()
     {
       return base.GetProviderCompilerContainers()