AutoMapper ProjectTo incompatible with EF5 Filtered Include

[ww2406]

Source/destination types

public class Blog
    {
        public int Id { get; set; }
        public List<Post> Posts { get; set; }
    }

public class BlogDTO
    {
        public int Id { get; set; }
        public List<PostDTO> Posts { get; set; }
    }

public class Post
    {
        public int Id { get; set; }
        public string Title { get; set; }
        
        public int AuthorId { get; set; }
        public Author Author { get; set; }
        
        public int BlogId { get; set; }
        public Blog Blog { get; set; }
    }

public class PostDTO
    {
        public int Id { get; set; }
        public string Title { get; set; }
        public AuthorDTO Author { get; set; }
    }

public class Author
    {
        public int Id { get; set; }
        public string Name { get; set; }
        
        public List<Post> Posts { get; set; }
    }

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

Mapping configuration

public MappingProfile()
        {
            CreateMap<Blog, BlogDTO>();
            CreateMap<Post, PostDTO>();
            CreateMap<Author, AuthorDTO>();
        }

Version: 10.1.1

EF Core is 5.0.8

Expected behavior

When using the ProjectTo functionality with EF Core 5's new filtered include functionality, the filtered include is not processed.

_ctx.A.Include(x => x.B.Where(y => y.C == D)).ProjectTo<E>(_mapper.ConfigurationProvider)

It's expected that this returns entity A with those records from B where property C equals a value D.

Actual behavior

In looking at the resulting SQL, the where clause is never materialized into the query--it proceeds as if the where clause is not there. If you remove the ProjectTo, the where clause is included in the query as expected.

Steps to reproduce

Please see my sample project at https://github.com/ww2406/AutomapperFilterIncludeIssue.

[lbargaoanu]

#3713 (comment)

[ww2406]

Got it! Can’t believe all this time I never knew that!! Learn something new everyday. Many thanks!