Can no longer translate operators over primitive collections or complex types on inheritance subtypes

[KotKaro]

Bug description

I'm mapping from one array to another array.
This code was working fine for EF 9 and it's not working in EF 10.

Do you maybe know how i can fix it?

Your code

IQueryable<NotificationFilterBase> filters = repository.GetUserFilters(userId);

        var query = filters.Select(x =>
            x is AlertNotificationFilter
                ? new
                {
                    Strategies = ((AlertNotificationFilter)x).Strategies.Select(strategy =>
                        strategy == AlertStrategy.DayTrade ? NotificationFilterAlertStrategy.DayTrade :
                        strategy == AlertStrategy.FiveStarTrade ? NotificationFilterAlertStrategy.FiveStarTrade :
                        strategy == AlertStrategy.LongTerm ? NotificationFilterAlertStrategy.LongTerm :
                        NotificationFilterAlertStrategy.Swing
                    ).ToArray()
                } : null).ToArray();

Stack traces

System.InvalidOperationException: The LINQ expression 'strategy => (int)strategy == 1 ? DayTrade : (int)strategy == 4 ? FiveStarTrade : (int)strategy == 3 ? LongTerm : Swing' could not be translated. Either rewrite the query in a form that can be translated, or switch to client evaluation explicitly by inserting a call to 'AsEnumerable', 'AsAsyncEnumerable', 'ToList', or 'ToListAsync'

Verbose output

EF Core version

10

Database provider

SQL Server

Target framework

10

Operating system

Windows 11

IDE

Rider

[roji]

Confirmed regression in 10.0.

AI Analysis

The translation failure is specifically triggered by the combination of:

• Querying against the base type (NotificationFilterBase).
• Using a type check (is AlertNotificationFilter) and cast in the projection.
  Projecting a primitive collection property of the derived type.
• If the query is performed directly on DbSet, the translation succeeds even in EF Core 10.

Minimal repro

await using var context = new MyContext();
await context.Database.EnsureDeletedAsync();
await context.Database.EnsureCreatedAsync();

var query = context.Filters
    .Where(x => ((SubType)x).Ints.Any())
    .ToArray();

public class MyContext : DbContext
{
    public DbSet<BaseType> Filters { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        => optionsBuilder
            .UseSqlServer(Environment.GetEnvironmentVariable("Test__SqlServer__DefaultConnection"))
            .LogTo(Console.WriteLine, LogLevel.Information);

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<BaseType>()
            .HasDiscriminator<string>("FilterType")
            .HasValue<SubType>("Alert");
    }
}

public abstract class BaseType
{
    public int Id { get; set; }
}

public class SubType : BaseType
{
    public int[] Ints { get; set; }
}