NullReferenceException in ForeignKeyPropertyDiscoveryConvention.Apply

[HappyNomad]

I just upgraded to 1.1 Preview 1 and then encountered this exception.

Trying to create a database using this context and model will reproduce the issue:

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

    public DbSet<A> As { get; set; }
}

public class A
{
    public int ID { get; set; }
    public L L1 { get; set; }
    public IList<PBase> L2 { get; set; }
}

public class L
{
    public int ID { get; set; }
    public IList<T> Ts { get; set; }
}

public class T : P
{
    public Q D { get; set; }
    public Q P1 { get; set; }
    public P P2 { get; set; }
}

public class P : PBase { }

public class Q : PBase { }

public abstract class PBase
{
    public int ID { get; set; }
    public string Stuff { get; set; }
}

Note that this model is almost the same as my second example in #6792. The only difference is the properties (or lack thereof) on T. Here has the same strange workaround of flipping the L1 and L2 names to make the exception disappear.

Here's the full exception text:

System.NullReferenceException was unhandled by user code
HResult=-2147467261
Message=Object reference not set to an instance of an object.
Source=Microsoft.EntityFrameworkCore
StackTrace:
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ForeignKeyPropertyDiscoveryConvention.Apply(InternalRelationshipBuilder relationshipBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ForeignKeyPropertyDiscoveryConvention.Apply(InternalEntityTypeBuilder entityTypeBuilder, Key key)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ConventionDispatcher.OnKeyRemoved(InternalEntityTypeBuilder entityTypeBuilder, Key key)
at Microsoft.EntityFrameworkCore.Metadata.Internal.EntityType.RemoveKey(Key key, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.EntityType.RemoveKey(IReadOnlyList1 properties, Boolean runConventions) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.RemoveKey(Key key, ConfigurationSource configurationSource, Boolean runConventions) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.RemoveKeyIfUnused(Key key) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.RemoveForeignKey(ForeignKey foreignKey, ConfigurationSource configurationSource, Boolean canOverrideSameSource, Boolean runConventions) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.RemoveForeignKey(ForeignKey foreignKey, List1 removedNavigations, List1 removedForeignKeys) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.GetOrCreateRelationshipBuilder(EntityType principalEntityType, EntityType dependentEntityType, Nullable1 navigationToPrincipal, Nullable1 navigationToDependent, IReadOnlyList1 dependentProperties, IReadOnlyList1 principalProperties, Nullable1 isRequired, Boolean removeCurrent, Nullable1 principalEndConfigurationSource, Nullable1 configurationSource, List1 removedNavigations, List1 removedForeignKeys, List1 addedForeignKeys, Nullable1& existingRelationshipInverted)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.ReplaceForeignKey(InternalEntityTypeBuilder principalEntityTypeBuilder, InternalEntityTypeBuilder dependentEntityTypeBuilder, Nullable1 navigationToPrincipal, Nullable1 navigationToDependent, IReadOnlyList1 dependentProperties, IReadOnlyList1 principalProperties, Nullable1 isUnique, Nullable1 isRequired, Nullable1 deleteBehavior, Boolean removeCurrent, Boolean oldRelationshipInverted, Nullable1 principalEndConfigurationSource, Nullable1 configurationSource, Boolean runConventions, List1 removedNavigations, List1 removedForeignKeys) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.ReplaceForeignKey(Nullable1 configurationSource, InternalEntityTypeBuilder principalEntityTypeBuilder, InternalEntityTypeBuilder dependentEntityTypeBuilder, Nullable1 navigationToPrincipal, Nullable1 navigationToDependent, IReadOnlyList1 dependentProperties, IReadOnlyList1 principalProperties, Nullable1 isUnique, Nullable1 isRequired, Nullable1 deleteBehavior, Boolean removeCurrent, Nullable1 principalEndConfigurationSource, Boolean oldRelationshipInverted, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.HasForeignKey(IReadOnlyList1 properties, EntityType dependentEntityType, Nullable1 configurationSource, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.HasForeignKey(IReadOnlyList1 properties, EntityType dependentEntityType, ConfigurationSource configurationSource) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalRelationshipBuilder.HasForeignKey(IReadOnlyList1 properties, ConfigurationSource configurationSource)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ForeignKeyPropertyDiscoveryConvention.Apply(InternalRelationshipBuilder relationshipBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ForeignKeyPropertyDiscoveryConvention.Apply(InternalPropertyBuilder propertyBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ConventionDispatcher.OnPropertyAdded(InternalPropertyBuilder propertyBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Internal.EntityType.AddProperty(String name, Type propertyType, MemberInfo memberInfo, ConfigurationSource configurationSource, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.EntityType.AddProperty(MemberInfo memberInfo, ConfigurationSource configurationSource, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.Property(Property existingProperty, String propertyName, Type propertyType, MemberInfo clrProperty, Nullable1 configurationSource) at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.Property(String propertyName, Type propertyType, MemberInfo clrProperty, Nullable1 configurationSource)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.Property(MemberInfo clrProperty, ConfigurationSource configurationSource)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.PropertyDiscoveryConvention.Apply(InternalEntityTypeBuilder entityTypeBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.PropertyDiscoveryConvention.Apply(InternalEntityTypeBuilder entityTypeBuilder, EntityType oldBaseType)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ConventionDispatcher.OnBaseEntityTypeSet(InternalEntityTypeBuilder entityTypeBuilder, EntityType previousBaseType)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalEntityTypeBuilder.HasBaseType(EntityType baseEntityType, ConfigurationSource configurationSource)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.BaseTypeDiscoveryConvention.Apply(InternalEntityTypeBuilder entityTypeBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ConventionDispatcher.OnEntityTypeAdded(InternalEntityTypeBuilder entityTypeBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.RelationshipDiscoveryConvention.Apply(InternalEntityTypeBuilder entityTypeBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Conventions.Internal.ConventionDispatcher.OnEntityTypeAdded(InternalEntityTypeBuilder entityTypeBuilder)
at Microsoft.EntityFrameworkCore.Metadata.Internal.Model.AddEntityType(EntityType entityType, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.Model.AddEntityType(Type type, ConfigurationSource configurationSource, Boolean runConventions)
at Microsoft.EntityFrameworkCore.Metadata.Internal.InternalModelBuilder.Entity(Type type, ConfigurationSource configurationSource, Boolean runConventions)
at Microsoft.EntityFrameworkCore.ModelBuilder.Entity(Type type)
at Microsoft.EntityFrameworkCore.Infrastructure.ModelSource.FindSets(ModelBuilder modelBuilder, DbContext context)
at Microsoft.EntityFrameworkCore.Infrastructure.Internal.RelationalModelSource.FindSets(ModelBuilder modelBuilder, DbContext context)
at Microsoft.EntityFrameworkCore.Infrastructure.ModelSource.CreateModel(DbContext context, IConventionSetBuilder conventionSetBuilder, IModelValidator validator)
at Microsoft.EntityFrameworkCore.Infrastructure.ModelSource.<>c__DisplayClass14_0.b__0(Object k)
at System.Collections.Concurrent.ConcurrentDictionary2.GetOrAdd(TKey key, Func2 valueFactory)
at Microsoft.EntityFrameworkCore.Infrastructure.ModelSource.GetModel(DbContext context, IConventionSetBuilder conventionSetBuilder, IModelValidator validator)
at Microsoft.EntityFrameworkCore.Internal.DbContextServices.CreateModel()
at Microsoft.EntityFrameworkCore.Internal.LazyRef1.get_Value() at Microsoft.EntityFrameworkCore.Internal.DbContextServices.get_Model() at Microsoft.EntityFrameworkCore.Infrastructure.EntityFrameworkServiceCollectionExtensions.<>c.<AddEntityFramework>b__0_6(IServiceProvider p) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitFactoryService(FactoryService factoryService, ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScoped(ScopedCallSite scopedCallSite, ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitConstructor(ConstructorCallSite constructorCallSite, ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScoped(ScopedCallSite scopedCallSite, ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.Resolve(IServiceCallSite callSite, ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceProvider.<>c__DisplayClass16_0.<RealizeService>b__0(ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceProvider.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.Storage.DatabaseProviderServices.GetService[TService]() at Microsoft.EntityFrameworkCore.Storage.Internal.SqlServerDatabaseProviderServices.get_RelationalDatabaseCreator() at Microsoft.EntityFrameworkCore.Storage.RelationalDatabaseProviderServices.get_Creator() at Microsoft.EntityFrameworkCore.Infrastructure.EntityFrameworkServiceCollectionExtensions.<>c.<AddEntityFramework>b__0_13(IServiceProvider p) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitFactoryService(FactoryService factoryService, ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.VisitScoped(ScopedCallSite scopedCallSite, ServiceProvider provider)
at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor2.VisitCallSite(IServiceCallSite callSite, TArgument argument) at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteRuntimeResolver.Resolve(IServiceCallSite callSite, ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceProvider.<>c__DisplayClass16_0.<RealizeService>b__0(ServiceProvider provider) at Microsoft.Extensions.DependencyInjection.ServiceProvider.GetService(Type serviceType) at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetService[T](IServiceProvider provider) at Microsoft.EntityFrameworkCore.Infrastructure.AccessorExtensions.GetService[TService](IInfrastructure1 accessor)
at Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.get_DatabaseCreator()
at Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.EnsureCreated()
at EFGetStarted.AspNetCore.NewDb.Startup.Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory, BloggingContext dataContext) in C:\Users\Adrian\Development\Examples\ASP.NET Core\EFGetStarted.AspNetCore.NewDb\src\EFGetStarted.AspNetCore.NewDb\Startup.cs:line 56
InnerException: