DbContext scaffold missing IndexerProperty for M2M relation after moving to EF Core 7

[SrdjanPaunovic]

After moving to version 7, we are now missing IndexerProperty in scaffolded DBContext for many to many relations.

DbContext, the problematic part of code:

entity.HasMany(d => d.MockupsNavigation).WithMany(p => p.Users)
    .UsingEntity<Dictionary<string, object>>(
        "UserMockup",
        r => r.HasOne<Mockup>().WithMany()
            .HasForeignKey("MockupId")
            .OnDelete(DeleteBehavior.ClientSetNull)
            .HasConstraintName("user_mockup_mockup_id_fkey"),
        l => l.HasOne<User>().WithMany()
            .HasForeignKey("UserId")
            .OnDelete(DeleteBehavior.ClientSetNull)
            .HasConstraintName("user_mockup_user_id_fkey"),
        j =>
        {
            j.HasKey("UserId", "MockupId").HasName("user_mockup_pkey");
            j.ToTable("user_mockup");

            //Missing code in EF7
            //j.IndexerProperty<long>("UserId").ValueGeneratedOnAdd().HasColumnName("user_id");
            //j.IndexerProperty<long>("MockupId").ValueGeneratedOnAdd().HasColumnName("mockup_id");
        });

We are getting an error on SaveChangesAsync when we try to connect user with mockup instance.

Exception message

PostgresException: 42703: column "MockupId" of relation "user_mockup" does not exist

After adding these 2 missing lines everything works fine.
We couldn't find in the documentation that something has been changed compared to the previous version.
Is there any configuration parameter that we need to add now to have the previous behavior?

Include provider and version information

EF Core version: 7.0
Database provider: PostgreSQL
Target framework: NET 7.0
Operating system:
IDE: (e.g. Visual Studio 2022 17.4)

[ajcvickers]

/cc @bricelam

[filipbekic01]

I confirm same problem on our end.

[miroljub1995]

Can we expect fix for this anytime soon? This breaks our scaffold.

[bricelam]

🩹 Workaround

Looks like you can work around it by using custom templates and adding the following to DbContext.t4 under the code that generates j.HasIndex.

            foreach (var property in joinEntityType.GetProperties())
            {
                var propertyFluentApiCalls = property.GetFluentApiCalls(annotationCodeGenerator);
                if (propertyFluentApiCalls == null)
                {
                    continue;
                }

                usings.AddRange(propertyFluentApiCalls.GetRequiredUsings());
#>
                        j.IndexerProperty<<#= code.Reference(property.ClrType) #>>(<#= code.Literal(property.Name) #>)<#= code.Fragment(propertyFluentApiCalls, indent: 7) #>;
<#
            }