NpgsqlArrayConverter.ArrayConversionExpression throws IndexOutOfRangeException when using a custom derived type for the collection

[PressXtoChris]

When using a custom derived class for a collection, the ArrayConversionExpression method throws an IndexOutOfRangeException when it attempts to get the (missing) generic type argument.

efcore.pg/src/EFCore.PG/Storage/ValueConversion/NpgsqlArrayConverter.cs

Line 142 in 35f0fd5

var iListType = typeof(IList<>).MakeGenericType(typeof(TInput).GetGenericArguments()[0]);

Example use case:

public class TestEntity(Guid id, CustomCollection values)
{
    public Guid Id { get; } = id;
    public CustomCollection Values { get; } = values;
}

public class CustomCollection : ReadOnlyCollection<string>
{
    public CustomCollection(string[] strings) : base(strings)
    {
        if (strings.Length == 0)
            throw new ArgumentException("At least one string must be provided", nameof(strings));
    }

    public bool SomeBusinessLogic() => this.Any(s => s.Contains("foo"));
}

public class TestDbContext : DbContext
{
    public DbSet<TestEntity> TestEntities { get; set; } = default!;
    public TestDbContext(DbContextOptions<TestDbContext> options) : base(options) { }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<TestEntity>()
            .ToTable("test_entities");

        modelBuilder.Entity<TestEntity>()
            .Property(x => x.Id)
            .HasColumnName("id");

        modelBuilder.Entity<TestEntity>()
            .PrimitiveCollection(x => x.Values)
            .HasColumnName("values")
            .ElementType()
            .HasConversion(typeof(CustomCollectionConversion));
    }
}

I think this could be resolved by getting the generic type arguments of the base class if TInput doesn't have any:

typeof(TInput).BaseType.GetGenericArguments()[0]

[roji]

Note to self: see also #3074 which may be related.

[roji]

I can't reproduce the precise error, probably because the code above is partial (e.g. CustomCollectionConversion is missing); when reporting issues, please always include a fully runnable, minimal code sample so that nothing is missing.

What I do get is the following exception:

/Users/roji/projects/test/bin/Debug/net8.0/Test
Unhandled exception. System.InvalidOperationException: Converter for element type 'CustomCollection' cannot be used for 'TestEntity.Values' because its element type is 'string'.
   at Microsoft.EntityFrameworkCore.Metadata.Internal.ElementType.SetValueConverter(ValueConverter converter, ConfigurationSource configurationSource)
   at Microsoft.EntityFrameworkCore.Metadata.Internal.ElementType.SetValueConverter(Type converterType, ConfigurationSource configurationSource)
   at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalElementTypeBuilder.HasConverter(Type converterType, ConfigurationSource configurationSource)
   at Microsoft.EntityFrameworkCore.Metadata.Builders.ElementTypeBuilder.HasConversion(Type conversionType)
   at BlogContext.OnModelCreating(ModelBuilder modelBuilder) in /Users/roji/projects/test/Program.cs:line 42

This error makes sense: you're doing HasConversion on the element type, rather than on the collection as a whole. changing the configuration to the following makes the program run without errors:

modelBuilder.Entity<TestEntity>()
    .PrimitiveCollection(x => x.Values)
    .HasColumnName("values")
    .Metadata.SetValueConverter(typeof(CustomCollectionConversion));

Full repro

await using var ctx = new BlogContext();
await ctx.Database.EnsureDeletedAsync();
await ctx.Database.EnsureCreatedAsync();

public class BlogContext : DbContext
{
    public DbSet<TestEntity> TestEntities { get; set; } = default!;

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        => optionsBuilder
            .UseNpgsql("Host=localhost;Username=test;Password=test")
            .LogTo(Console.WriteLine, LogLevel.Information)
            .EnableSensitiveDataLogging();

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<TestEntity>()
            .ToTable("test_entities");

        modelBuilder.Entity<TestEntity>()
            .Property(x => x.Id)
            .HasColumnName("id");

        modelBuilder.Entity<TestEntity>()
            .PrimitiveCollection(x => x.Values)
            .HasColumnName("values")
            .Metadata.SetValueConverter(typeof(CustomCollectionConversion));

        // modelBuilder.Entity<TestEntity>()
        //     .PrimitiveCollection(x => x.Values)
        //     .HasColumnName("values")
        //     .ElementType()
        //     .HasConversion(typeof(CustomCollectionConversion));
    }

    public class CustomCollectionConversion()
        : ValueConverter<CustomCollection, string[]>(
            c => c.ToArray(),
            a => new CustomCollection(a));
}

public class Blog
{
    public int Id { get; set; }
    public string Name { get; set; }
}

public class TestEntity(Guid id, CustomCollection values)
{
    public Guid Id { get; } = id;
    public CustomCollection Values { get; } = values;
}

public class CustomCollection : ReadOnlyCollection<string>
{
    public CustomCollection(string[] strings) : base(strings)
    {
        if (strings.Length == 0)
            throw new ArgumentException("At least one string must be provided", nameof(strings));
    }

    public bool SomeBusinessLogic() => this.Any(s => s.Contains("foo"));
}

If this doesn't fix your problem in some way, can you please share a full, runnable repro (like the code just above) that shows the problem?

[PressXtoChris]

Apologies, didn't realise I'd left it off. My CustomCollection converter simply converted from string to string.

public class CustomCollectionConversion() : ValueConverter<string, string>(
    v => v,
    v => v);

Since using .HasConversion<string>() caused the following exception:

Unhandled exception. System.InvalidCastException: Unable to cast object of type 'System.String[]' to type 'NpgsqlArrayConversion.CustomCollection'.
   at lambda_method13(Closure, InternalEntityEntry)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.InternalEntityEntry.OriginalValues..ctor(InternalEntityEntry entry)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.InternalEntityEntry.EnsureOriginalValues()
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.InternalEntityEntrySubscriber.SnapshotAndSubscribe(InternalEntityEntry entry)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.StartTracking(InternalEntityEntry entry)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.InternalEntityEntry.SetEntityState(EntityState oldState, EntityState newState, Boolean acceptChanges, Boolean modifyProper
ties)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.InternalEntityEntry.SetEntityState(EntityState entityState, Boolean acceptChanges, Boolean modifyProperties, Nullable`1 fo
rceStateWhenUnknownKey, Nullable`1 fallbackState)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.EntityGraphAttacher.PaintAction(EntityEntryGraphNode`1 node)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.EntityEntryGraphIterator.TraverseGraph[TState](EntityEntryGraphNode`1 node, Func`2 handleNode)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.EntityGraphAttacher.AttachGraph(InternalEntityEntry rootEntry, EntityState targetState, EntityState storeGeneratedWithKeyS
etTargetState, Boolean forceStateWhenUnknownKey)
   at Microsoft.EntityFrameworkCore.Internal.InternalDbSet`1.SetEntityState(InternalEntityEntry entry, EntityState entityState)
   at Microsoft.EntityFrameworkCore.Internal.InternalDbSet`1.Add(TEntity entity)

Here's my full code:

Full repro of above

Model.cs

using System.Collections.ObjectModel;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;

namespace NpgsqlArrayConversion;

public class TestEntity(Guid id, CustomCollection values)
{
    public Guid Id { get; } = id;
    public CustomCollection Values { get; } = values;

    private TestEntity() : this(default, default!) { }
}

public class CustomCollection : ReadOnlyCollection<string>
{
    public CustomCollection(string[] strings) : base(strings)
    {
        if (strings.Length == 0)
            throw new ArgumentException("At least one string must be provided", nameof(strings));
    }

    public bool SomeBusinessLogic() => this.Any(s => s.Contains("foo"));
}

public class TestDbContext : DbContext
{
    public DbSet<TestEntity> TestEntities { get; set; } = default!;
    public TestDbContext(DbContextOptions<TestDbContext> options) : base(options) { }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<TestEntity>()
            .ToTable("test_entities");

        modelBuilder.Entity<TestEntity>()
            .Property(x => x.Id)
            .HasColumnName("id");

        modelBuilder.Entity<TestEntity>()
            .PrimitiveCollection(x => x.Values)
            .HasColumnName("values")
            .ElementType()
            .HasConversion(typeof(CustomCollectionConversion));
    }
}

public class CustomCollectionConversion() : ValueConverter<string, string>(
    v => v,
    v => v);

public class TestDbContextFactory : IDesignTimeDbContextFactory<TestDbContext>
{
    public TestDbContext CreateDbContext(string[] args)
    {
        var optionsBuilder = new DbContextOptionsBuilder<TestDbContext>();
        optionsBuilder.UseNpgsql("Host=localhost;Database=postgres;Username=postgres;Password=password");
        return new TestDbContext(optionsBuilder.Options);
    }
}

Program.cs

using NpgsqlArrayConversion;

using var db = new TestDbContextFactory().CreateDbContext(Array.Empty<string>());

Console.WriteLine("Inserting a new item");

var strings = new[] { "One", "Two" };
db.TestEntities.Add(new TestEntity(Guid.NewGuid(), new CustomCollection(strings)));

db.SaveChanges();
Console.WriteLine("Saved");

Also worth noting that in my real-world use case, I've got a wrapper class for my strings:

Repro of real-world case

Model.cs

using System.Collections.ObjectModel;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;

namespace NpgsqlArrayConversion;

public class TestEntity(Guid id, CustomCollection values)
{
    public Guid Id { get; } = id;
    public CustomCollection Values { get; } = values;

    private TestEntity() : this(default, default!) { }
}

public class CustomCollection : ReadOnlyCollection<StringWrapper>
{
    public CustomCollection(string[] strings) : base(strings.Select(StringWrapper.FromString).ToList())
    {
        if (strings.Length == 0)
            throw new ArgumentException("At least one string must be provided", nameof(strings));
    }

    public bool SomeBusinessLogic() => this.Any(s => s.Value.Contains("foo"));
}

public class StringWrapper
{
    public string Value { get; }
    private StringWrapper(string value) => Value = value;
    public static StringWrapper FromString(string value) => new(value);
}

public class TestDbContext : DbContext
{
    public DbSet<TestEntity> TestEntities { get; set; } = default!;
    public TestDbContext(DbContextOptions<TestDbContext> options) : base(options) { }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<TestEntity>()
            .ToTable("test_entities");

        modelBuilder.Entity<TestEntity>()
            .Property(x => x.Id)
            .HasColumnName("id");

        modelBuilder.Entity<TestEntity>()
            .PrimitiveCollection(x => x.Values)
            .HasColumnName("values")
            .ElementType()
            .HasConversion(typeof(StringWrapperConverter));
    }
}

public class StringWrapperConverter() : ValueConverter<StringWrapper, string>(
    v => v.Value,
    v => StringWrapper.FromString(v));

public class TestDbContextFactory : IDesignTimeDbContextFactory<TestDbContext>
{
    public TestDbContext CreateDbContext(string[] args)
    {
        var optionsBuilder = new DbContextOptionsBuilder<TestDbContext>();
        optionsBuilder.UseNpgsql("Host=localhost;Database=postgres;Username=postgres;Password=password");
        return new TestDbContext(optionsBuilder.Options);
    }
}

Program.cs

using NpgsqlArrayConversion;

using var db = new TestDbContextFactory().CreateDbContext(Array.Empty<string>());

Console.WriteLine("Inserting a new item");

var strings = new[] { "One", "Two" };
db.TestEntities.Add(new TestEntity(Guid.NewGuid(), new CustomCollection(strings)));

db.SaveChanges();
Console.WriteLine("Saved");

Using Microsoft.EntityFrameworkCore 8.0.2, and Ngpsql.EntityFrameworkCore.PostgreSQL 8.0.2

When I try the SetValueConverter implementation:

SetValueConverter implementation

Model.cs

using System.Collections.ObjectModel;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;

namespace NpgsqlArrayConversion;

public class TestEntity(Guid id, CustomCollection values)
{
    public Guid Id { get; } = id;
    public CustomCollection Values { get; } = values;

    private TestEntity() : this(default, default!) { }
}

public class CustomCollection : ReadOnlyCollection<StringWrapper>
{
    public CustomCollection(string[] strings) : base(strings.Select(StringWrapper.FromString).ToList())
    {
        if (strings.Length == 0)
            throw new ArgumentException("At least one string must be provided", nameof(strings));
    }

    public bool SomeBusinessLogic() => this.Any(s => s.Value.Contains("foo"));
}

public class StringWrapper
{
    public string Value { get; }

    private StringWrapper(string value) => Value = value;

    public static StringWrapper FromString(string value) => new(value);
}

public class TestDbContext : DbContext
{
    public DbSet<TestEntity> TestEntities { get; set; } = default!;
    public TestDbContext(DbContextOptions<TestDbContext> options) : base(options) { }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<TestEntity>()
            .ToTable("test_entities");

        modelBuilder.Entity<TestEntity>()
            .Property(x => x.Id)
            .HasColumnName("id");

        modelBuilder.Entity<TestEntity>()
            .PrimitiveCollection(x => x.Values)
            .HasColumnName("values")
            .Metadata.SetValueConverter(typeof(CustomCollectionConverter));
    }
}

public class CustomCollectionConverter() : ValueConverter<CustomCollection, string[]>(
    c => c.Select(x => x.Value).ToArray(),
    a => new CustomCollection(a));

public class TestDbContextFactory : IDesignTimeDbContextFactory<TestDbContext>
{
    public TestDbContext CreateDbContext(string[] args)
    {
        var optionsBuilder = new DbContextOptionsBuilder<TestDbContext>();
        optionsBuilder.UseNpgsql("Host=localhost;Database=postgres;Username=postgres;Password=password");
        return new TestDbContext(optionsBuilder.Options);
    }
}

Program.cs is the same as above

I get the following exception:

Unhandled exception. System.InvalidOperationException: The 'CustomCollection' property 'TestEntity.Values' could not be mapped because the database provider does not support this typ
e. Consider converting the property value to a type supported by the database using a value converter. See https://aka.ms/efcore-docs-value-converters for more information. Alternate
ly, exclude the property from the model using the '[NotMapped]' attribute or by using 'EntityTypeBuilder.Ignore' in 'OnModelCreating'.
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelValidator.ThrowPropertyNotMappedException(String propertyType, IConventionTypeBase typeBase, IConventionProperty unmappedPrope
rty)
   at Microsoft.EntityFrameworkCore.Infrastructure.RelationalModelValidator.ThrowPropertyNotMappedException(String propertyType, IConventionTypeBase typeBase, IConventionProperty unm
appedProperty)
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelValidator.<ValidatePropertyMapping>g__Validate|7_0(IConventionTypeBase typeBase, <>c__DisplayClass7_0&)
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelValidator.ValidatePropertyMapping(IModel model, IDiagnosticsLogger`1 logger)
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelValidator.Validate(IModel model, IDiagnosticsLogger`1 logger)
   at Microsoft.EntityFrameworkCore.Infrastructure.RelationalModelValidator.Validate(IModel model, IDiagnosticsLogger`1 logger)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Infrastructure.Internal.NpgsqlModelValidator.Validate(IModel model, IDiagnosticsLogger`1 logger)
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelRuntimeInitializer.Initialize(IModel model, Boolean designTime, IDiagnosticsLogger`1 validationLogger)
   at Microsoft.EntityFrameworkCore.Infrastructure.ModelSource.GetModel(DbContext context, ModelCreationDependencies modelCreationDependencies, Boolean designTime)
   at Microsoft.EntityFrameworkCore.Internal.DbContextServices.CreateModel(Boolean designTime)
   at Microsoft.EntityFrameworkCore.Internal.DbContextServices.get_Model()
   at Microsoft.EntityFrameworkCore.Infrastructure.EntityFrameworkServicesBuilder.<>c.<TryAddCoreServices>b__8_4(IServiceProvider p)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitFactory(FactoryCallSite factoryCallSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext context)        
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext context)        
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext context)        
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext context)        
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, RuntimeResolverContext context)        
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSiteMain(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitCache(ServiceCallSite callSite, RuntimeResolverContext context, ServiceProviderEngineScope s
erviceProviderEngine, RuntimeResolverLock lockType)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScopeCache(ServiceCallSite callSite, RuntimeResolverContext context)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor`2.VisitCallSite(ServiceCallSite callSite, TArgument argument)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.Resolve(ServiceCallSite callSite, ServiceProviderEngineScope scope)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.DynamicServiceProviderEngine.<>c__DisplayClass2_0.<RealizeService>b__0(ServiceProviderEngineScope scope)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.GetService(ServiceIdentifier serviceIdentifier, ServiceProviderEngineScope serviceProviderEngineScope)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngineScope.GetService(Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
   at Microsoft.EntityFrameworkCore.DbContext.get_DbContextDependencies()
   at Microsoft.EntityFrameworkCore.DbContext.get_ContextServices()
   at Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider()
   at Microsoft.EntityFrameworkCore.DbContext.get_DbContextDependencies()
   at Microsoft.EntityFrameworkCore.DbContext.Microsoft.EntityFrameworkCore.Internal.IDbContextDependencies.get_StateManager()
   at Microsoft.EntityFrameworkCore.Internal.InternalDbSet`1.EntryWithoutDetectChanges(TEntity entity)
   at Microsoft.EntityFrameworkCore.Internal.InternalDbSet`1.Add(TEntity entity)
at Program.<Main>$(String[] args) in \NpgsqlArrayConversion\Program.cs:line 10