Include Function Backward Compatibility For Generic Repositories

[timbilt]

Support of generic repositories is very important. A major problem with EF 7/Core is that the new syntax for the Include/ThenInclude functions provide more intuitive readability, but make it very difficult to write a generic repository to include navigation relationships. We were always able to pass a list of object-returning lamdas based on the queried entity type to select any relational table we want.

rep.GetAll<User>(u => u.Company.Country, u => u.Files.Select(f => f.FileDetail))

The above query which gets all users and "Include"s the users (Company, Country, Files, and FileDetail), now throws an error in EF 7/Core. This code should have been supported whilst adding the intuitive Include/ThenInclude. But to write a generic repository that supports the above code is very hard. And if it's restructured to support Include/ThenInclude the parameters will be some ugly object. Please allow us to continue using our existing generic repositories or provide a solution for generic repositories that allows including related tables via navigation properties.

Thanks so much

[rowanmiller]

EF Team Triage: Our plan is to also have string based include, we just haven't implemented it yet. With the new C# nameof feature, this gives a decent way to handle these more dynamic scenarios. At this stage, we aren't really keen to enable a second pattern for lambda based includes.