Inmemory DB throws ArgumentException when adding an item in a second service collection

[JanEggers]

im using efcore in memory 2.2.3

and this is throwing argument exception when adding s3 (savechanges):

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Storage;
using Microsoft.Extensions.DependencyInjection;
using Xunit;

namespace EntityFrameworkTestBugRepro
{
    public class EntityFrameworkTestBugRepro
    {

        public class TestContext : DbContext
        {
            public TestContext(DbContextOptions<TestContext> options)
                : base(options)
            {

            }

            public DbSet<TestObject> Items { get; set; }
        }

        public class TestObject
        {
            [Key]
            public int Id { get; set; }

            public string Name { get; set; }
        }

        [Fact]
        public async Task InMemoryStoreWorks_Repro()
        {
            await Task.Yield();

            var root = new InMemoryDatabaseRoot();

            using (var services = new ServiceCollection()
                .AddDbContext<TestContext>(o => o.UseInMemoryDatabase("Foo", root))
                .BuildServiceProvider())
            {
                using (var scope = services.CreateScope())
                {
                    var dbcontext = scope.ServiceProvider.GetRequiredService<TestContext>();

                    dbcontext.Items.Add(new TestObject { Name = "s1" });

                    dbcontext.SaveChanges();
                }


                using (var scope = services.CreateScope())
                {
                    var dbcontext = scope.ServiceProvider.GetRequiredService<TestContext>();

                    dbcontext.Items.Add(new TestObject { Name = "s2" });

                    dbcontext.SaveChanges();
                }

            }

            using (var services = new ServiceCollection()
                .AddDbContext<TestContext>(o => o.UseInMemoryDatabase("Foo", root))
                .BuildServiceProvider())
            {
                using (var scope = services.CreateScope())
                {
                    var dbcontext = scope.ServiceProvider.GetRequiredService<TestContext>();

                    Assert.Equal(2, dbcontext.Items.Count());

                    dbcontext.Items.Add(new TestObject { Name = "s3" });

                    dbcontext.SaveChanges();
                }
            }
        }
    }
}

ArgumentException: Ein Element mit dem gleichen Schlüssel wurde bereits hinzugefügt.
   bei System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   bei System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   bei Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryTable`1.Create(IUpdateEntry entry)
   bei Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryStore.ExecuteTransaction(IReadOnlyList`1 entries, IDiagnosticsLogger`1 updateLogger)
   bei Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryDatabase.SaveChanges(IReadOnlyList`1 entries)
   bei Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(IReadOnlyList`1 entriesToSave)
   bei Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(Boolean acceptAllChangesOnSuccess)
   bei Microsoft.EntityFrameworkCore.DbContext.SaveChanges(Boolean acceptAllChangesOnSuccess)
   bei Microsoft.EntityFrameworkCore.DbContext.SaveChanges()

[ajcvickers]

Duplicate of #6872

[JanEggers]

@ajcvickers why is this a duplicate? The other issue is about resetting the key value generator and for my Szenario it has to consider existing rows. Can you please Post a workaound because it is not clear for me from the referenced issue

[JanEggers]

never mind i updated to 3.0.0 preview 6 and with that version it is behaving correctly

[ajcvickers]

@JanEggers The fix for that issue also included taking into account existing IDs in the table. It was basically a complete overhaul of the strategy to make it behave more like the relational equivalents.